1551 lines
68 KiB
Zig
1551 lines
68 KiB
Zig
const DiffMatchPatch = @This();
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const std = @import("std");
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const testing = std.testing;
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const ArrayListUnmanaged = std.ArrayListUnmanaged;
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/// DMP with default configuration options
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pub const default = DiffMatchPatch{};
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pub const Diff = struct {
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pub const Operation = enum {
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insert,
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delete,
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equal,
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};
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operation: Operation,
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text: []const u8,
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pub fn format(value: Diff, _: anytype, _: anytype, writer: anytype) !void {
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try writer.print("({s}, \"{s}\")", .{
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switch (value.operation) {
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.equal => "",
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.insert => "+",
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.delete => "-",
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},
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value.text,
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});
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}
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pub fn init(operation: Operation, text: []const u8) Diff {
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return .{ .operation = operation, .text = text };
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}
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pub fn eql(a: Diff, b: Diff) bool {
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return a.operation == b.operation and std.mem.eql(u8, a.text, b.text);
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}
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};
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/// Number of microseconds to map a diff before giving up (0 for infinity).
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diff_timeout: u64 = 1 * std.time.us_per_s,
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/// Cost of an empty edit operation in terms of edit characters.
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diff_edit_cost: u16 = 4,
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/// At what point is no match declared (0.0 = perfection, 1.0 = very loose).
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match_threshold: f32 = 0.5,
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/// How far to search for a match (0 = exact location, 1000+ = broad match).
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/// A match this many characters away from the expected location will add
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/// 1.0 to the score (0.0 is a perfect match).
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match_distance: u32 = 1000,
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/// The number of bits in an int.
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match_max_bits: u16 = 32,
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/// When deleting a large block of text (over ~64 characters), how close
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/// do the contents have to be to match the expected contents. (0.0 =
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/// perfection, 1.0 = very loose). Note that Match_Threshold controls
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/// how closely the end points of a delete need to match.
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patch_delete_threshold: f32 = 0.5,
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/// Chunk size for context length.
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patch_margin: u16 = 4,
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pub const DiffError = error{OutOfMemory};
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/// It is recommended that you use an Arena for this operation.
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pub fn diff(
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dmp: DiffMatchPatch,
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allocator: std.mem.Allocator,
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before: []const u8,
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after: []const u8,
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/// If false, then don't run a line-level diff first
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/// to identify the changed areas. If true, then run
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/// a faster slightly less optimal diff.
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check_lines: bool,
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) DiffError!ArrayListUnmanaged(Diff) {
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const deadline = @intCast(u64, std.time.microTimestamp()) + dmp.diff_timeout;
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return dmp.diffInternal(allocator, before, after, check_lines, deadline);
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}
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fn diffInternal(
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dmp: DiffMatchPatch,
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allocator: std.mem.Allocator,
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before: []const u8,
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after: []const u8,
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check_lines: bool,
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deadline: u64,
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) DiffError!ArrayListUnmanaged(Diff) {
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// Check for equality (speedup).
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var diffs = ArrayListUnmanaged(Diff){};
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if (std.mem.eql(u8, before, after)) {
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if (before.len != 0) {
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try diffs.append(allocator, Diff{ .operation = .equal, .text = before });
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}
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return diffs;
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}
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// Trim off common prefix (speedup).
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var common_length = diffCommonPrefix(before, after);
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const common_prefix = before[0..common_length];
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var trimmed_before = before[common_length..];
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var trimmed_after = after[common_length..];
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// Trim off common suffix (speedup).
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common_length = diffCommonSuffix(before, after);
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var common_suffix = before[before.len - common_length ..];
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trimmed_before = trimmed_before[0 .. trimmed_before.len - common_length];
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trimmed_after = trimmed_after[0 .. trimmed_after.len - common_length];
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// Compute the diff on the middle block.
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diffs = try dmp.diffCompute(allocator, before, after, check_lines, deadline);
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// Restore the prefix and suffix.
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if (common_prefix.len != 0) {
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try diffs.insert(allocator, 0, Diff{ .operation = .equal, .text = common_prefix });
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}
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if (common_suffix.len != 0) {
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try diffs.append(allocator, Diff{ .operation = .equal, .text = common_suffix });
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}
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try diffCleanupMerge(allocator, &diffs);
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return diffs;
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}
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fn diffCommonPrefix(before: []const u8, after: []const u8) usize {
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const n = std.math.min(before.len, after.len);
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var i: usize = 0;
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while (i < n) : (i += 1) {
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if (before[i] != after[i]) {
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return i;
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}
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}
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return n;
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}
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fn diffCommonSuffix(before: []const u8, after: []const u8) usize {
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const n = std.math.min(before.len, after.len);
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var i: usize = 1;
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while (i <= n) : (i += 1) {
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if (before[before.len - i] != after[after.len - i]) {
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return i - 1;
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}
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}
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return n;
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}
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fn diffCompute(
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dmp: DiffMatchPatch,
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allocator: std.mem.Allocator,
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before: []const u8,
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after: []const u8,
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check_lines: bool,
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deadline: u64,
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) DiffError!ArrayListUnmanaged(Diff) {
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var diffs = ArrayListUnmanaged(Diff){};
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if (before.len == 0) {
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// Just add some text (speedup).
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try diffs.append(allocator, Diff{ .operation = .insert, .text = after });
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return diffs;
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}
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if (after.len == 0) {
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// Just delete some text (speedup).
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try diffs.append(allocator, Diff{ .operation = .delete, .text = before });
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return diffs;
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}
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const long_text = if (before.len > after.len) before else after;
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const short_text = if (before.len > after.len) after else before;
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var short_text_in_long_text_index = std.mem.indexOf(u8, long_text, short_text);
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if (short_text_in_long_text_index) |index| {
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// Shorter text is inside the longer text (speedup).
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const op: Diff.Operation = if (before.len > after.len)
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.delete
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else
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.insert;
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try diffs.append(allocator, Diff{ .operation = op, .text = long_text[0..index] });
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try diffs.append(allocator, Diff{ .operation = .equal, .text = short_text });
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try diffs.append(allocator, Diff{ .operation = op, .text = long_text[index + short_text.len ..] });
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return diffs;
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}
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if (short_text.len == 1) {
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// Single character string.
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// After the previous speedup, the character can't be an equality.
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try diffs.append(allocator, Diff{ .operation = .delete, .text = before });
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try diffs.append(allocator, Diff{ .operation = .insert, .text = after });
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return diffs;
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}
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// Check to see if the problem can be split in two.
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var maybe_half_match = try dmp.diffHalfMatch(allocator, before, after);
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if (maybe_half_match) |half_match| {
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// A half-match was found, sort out the return data.
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// Send both pairs off for separate processing.
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var diffs_a = try dmp.diffInternal(allocator, half_match.prefix_before, half_match.prefix_after, check_lines, deadline);
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var diffs_b = try dmp.diffInternal(allocator, half_match.suffix_before, half_match.suffix_after, check_lines, deadline);
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defer diffs_b.deinit(allocator);
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// Merge the results.
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diffs = diffs_a;
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try diffs.append(allocator, Diff{ .operation = .equal, .text = half_match.common_middle });
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try diffs.appendSlice(allocator, diffs_b.items);
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return diffs;
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}
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if (check_lines and before.len > 100 and after.len > 100) {
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return dmp.diffLineMode(allocator, before, after, deadline);
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}
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return dmp.diffBisect(allocator, before, after, deadline);
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}
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const HalfMatchResult = struct {
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prefix_before: []const u8,
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suffix_before: []const u8,
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prefix_after: []const u8,
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suffix_after: []const u8,
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common_middle: []const u8,
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};
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fn diffHalfMatch(
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dmp: DiffMatchPatch,
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allocator: std.mem.Allocator,
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before: []const u8,
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after: []const u8,
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) DiffError!?HalfMatchResult {
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if (dmp.diff_timeout <= 0) {
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// Don't risk returning a non-optimal diff if we have unlimited time.
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return null;
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}
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const long_text = if (before.len > after.len) before else after;
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const short_text = if (before.len > after.len) after else before;
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if (long_text.len < 4 or short_text.len * 2 < long_text.len) {
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return null; // Pointless.
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}
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// First check if the second quarter is the seed for a half-match.
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var half_match_1 = try dmp.diffHalfMatchInternal(allocator, long_text, short_text, (long_text.len + 3) / 4);
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// Check again based on the third quarter.
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var half_match_2 = try dmp.diffHalfMatchInternal(allocator, long_text, short_text, (long_text.len + 1) / 2);
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var half_match: ?HalfMatchResult = null;
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if (half_match_1 == null and half_match_2 == null) {
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return null;
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} else if (half_match_2 == null) {
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half_match = half_match_1.?;
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} else if (half_match_1 == null) {
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half_match = half_match_2.?;
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} else {
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// Both matched. Select the longest.
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half_match = if (half_match_1.?.common_middle.len > half_match_2.?.common_middle.len) half_match_1 else half_match_2;
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}
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// A half-match was found, sort out the return data.
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if (before.len > after.len) {
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return half_match;
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} else {
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const half_match_yes = half_match.?;
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return .{
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.prefix_before = half_match_yes.prefix_after,
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.suffix_before = half_match_yes.suffix_after,
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.prefix_after = half_match_yes.prefix_before,
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.suffix_after = half_match_yes.suffix_before,
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.common_middle = half_match_yes.common_middle,
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};
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}
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}
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fn diffHalfMatchInternal(
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_: DiffMatchPatch,
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allocator: std.mem.Allocator,
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long_text: []const u8,
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short_text: []const u8,
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i: usize,
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) DiffError!?HalfMatchResult {
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// Start with a 1/4 length Substring at position i as a seed.
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const seed = long_text[i .. i + long_text.len / 4];
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var j: isize = -1;
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var best_common = std.ArrayListUnmanaged(u8){};
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var best_long_text_a: []const u8 = "";
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var best_long_text_b: []const u8 = "";
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var best_short_text_a: []const u8 = "";
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var best_short_text_b: []const u8 = "";
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while (j < short_text.len and b: {
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j = @intCast(isize, std.mem.indexOf(u8, short_text[@intCast(usize, j + 1)..], seed) orelse break :b false) + j + 1;
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break :b true;
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}) {
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var prefix_length = diffCommonPrefix(long_text[i..], short_text[@intCast(usize, j)..]);
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var suffix_length = diffCommonSuffix(long_text[0..i], short_text[0..@intCast(usize, j)]);
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if (best_common.items.len < suffix_length + prefix_length) {
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best_common.items.len = 0;
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try best_common.appendSlice(allocator, short_text[@intCast(usize, j - @intCast(isize, suffix_length)) .. @intCast(usize, j - @intCast(isize, suffix_length)) + suffix_length]);
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try best_common.appendSlice(allocator, short_text[@intCast(usize, j) .. @intCast(usize, j) + prefix_length]);
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best_long_text_a = long_text[0 .. i - suffix_length];
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best_long_text_b = long_text[i + prefix_length ..];
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best_short_text_a = short_text[0..@intCast(usize, j - @intCast(isize, suffix_length))];
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best_short_text_b = short_text[@intCast(usize, j + @intCast(isize, prefix_length))..];
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}
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}
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if (best_common.items.len * 2 >= long_text.len) {
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return .{
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.prefix_before = best_long_text_a,
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.suffix_before = best_long_text_b,
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.prefix_after = best_short_text_a,
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.suffix_after = best_short_text_b,
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.common_middle = best_common.items,
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};
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} else {
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return null;
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}
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}
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fn diffBisect(
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dmp: DiffMatchPatch,
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allocator: std.mem.Allocator,
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before: []const u8,
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after: []const u8,
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deadline: u64,
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) error{OutOfMemory}!ArrayListUnmanaged(Diff) {
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const max_d = (before.len + after.len + 1) / 2;
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const v_offset = max_d;
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const v_length = 2 * max_d;
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var v1 = try ArrayListUnmanaged(isize).initCapacity(allocator, v_length);
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v1.items.len = v_length;
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var v2 = try ArrayListUnmanaged(isize).initCapacity(allocator, v_length);
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v2.items.len = v_length;
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var x: usize = 0;
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while (x < v_length) : (x += 1) {
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v1.items[x] = -1;
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v2.items[x] = -1;
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}
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v1.items[v_offset + 1] = 0;
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v2.items[v_offset + 1] = 0;
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var delta = @intCast(isize, before.len) - @intCast(isize, after.len);
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// If the total number of characters is odd, then the front path will
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// collide with the reverse path.
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var front = (@mod(delta, 2) != 0);
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// Offsets for start and end of k loop.
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// Prevents mapping of space beyond the grid.
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var k1start: usize = 0;
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var k1end: usize = 0;
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var k2start: usize = 0;
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var k2end: usize = 0;
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var d: usize = 0;
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while (d < max_d) : (d += 1) {
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// Bail out if deadline is reached.
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if (@intCast(u64, std.time.microTimestamp()) > deadline) {
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break;
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}
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// Walk the front path one step.
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var k1: isize = -@intCast(isize, d) + @intCast(isize, k1start);
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while (k1 <= d - k1end) : (k1 += 2) {
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var k1_offset: isize = @intCast(isize, v_offset) + k1;
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var x1: isize = 0;
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if (k1 == -@intCast(isize, d) or k1 != d and v1.items[@intCast(usize, k1_offset - 1)] < v1.items[@intCast(usize, k1_offset + 1)]) {
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x1 = v1.items[@intCast(usize, k1_offset + 1)];
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} else {
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x1 = v1.items[@intCast(usize, k1_offset - 1)] + 1;
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}
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var y1: isize = x1 - k1;
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while (x1 < before.len and y1 < after.len and before[@intCast(usize, x1)] == after[@intCast(usize, y1)]) {
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x1 += 1;
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y1 += 1;
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}
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v1.items[@intCast(usize, k1_offset)] = x1;
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if (x1 > before.len) {
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// Ran off the right of the graph.
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k1end += 2;
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} else if (y1 > after.len) {
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// Ran off the bottom of the graph.
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k1start += 2;
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} else if (front) {
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var k2_offset: isize = @intCast(isize, v_offset) + delta - k1;
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if (k2_offset >= 0 and k2_offset < v_length and v2.items[@intCast(usize, k2_offset)] != -1) {
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// Mirror x2 onto top-left coordinate system.
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var x2: isize = @intCast(isize, before.len) - v2.items[@intCast(usize, k2_offset)];
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if (x1 >= x2) {
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// Overlap detected.
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return dmp.diffBisectSplit(allocator, before, after, x1, y1, deadline);
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}
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}
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}
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}
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// Walk the reverse path one step.
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var k2: isize = -@intCast(isize, d) + @intCast(isize, k2start);
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while (k2 <= d - k2end) : (k2 += 2) {
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var k2_offset: isize = @intCast(isize, v_offset) + k2;
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var x2: isize = 0;
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if (k2 == -@intCast(isize, d) or k2 != d and v2.items[@intCast(usize, k2_offset - 1)] < v2.items[@intCast(usize, k2_offset + 1)]) {
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x2 = v2.items[@intCast(usize, k2_offset + 1)];
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} else {
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x2 = v2.items[@intCast(usize, k2_offset - 1)] + 1;
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}
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var y2: isize = x2 - k2;
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while (x2 < before.len and y2 < after.len and before[@intCast(usize, @intCast(isize, before.len) - x2 - 1)] == after[@intCast(usize, @intCast(isize, after.len) - y2 - 1)]) {
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x2 += 1;
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y2 += 1;
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}
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v2.items[@intCast(usize, k2_offset)] = x2;
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if (x2 > before.len) {
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// Ran off the left of the graph.
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k2end += 2;
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} else if (y2 > after.len) {
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// Ran off the top of the graph.
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k2start += 2;
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} else if (!front) {
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var k1_offset: isize = @intCast(isize, v_offset) + delta - k2;
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if (k1_offset >= 0 and k1_offset < v_length and v1.items[@intCast(usize, k1_offset)] != -1) {
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var x1: isize = v1.items[@intCast(usize, k1_offset)];
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var y1: isize = @intCast(isize, v_offset) + x1 - k1_offset;
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// Mirror x2 onto top-left coordinate system.
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x2 = @intCast(isize, before.len) - v2.items[@intCast(usize, k2_offset)];
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if (x1 >= x2) {
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// Overlap detected.
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return dmp.diffBisectSplit(allocator, before, after, x1, y1, deadline);
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}
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}
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}
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}
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}
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// Diff took too long and hit the deadline or
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// number of diffs equals number of characters, no commonality at all.
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var diffs = ArrayListUnmanaged(Diff){};
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try diffs.append(allocator, Diff{ .operation = .delete, .text = before });
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try diffs.append(allocator, Diff{ .operation = .insert, .text = after });
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return diffs;
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}
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|
|
fn diffBisectSplit(
|
|
dmp: DiffMatchPatch,
|
|
allocator: std.mem.Allocator,
|
|
text1: []const u8,
|
|
text2: []const u8,
|
|
x: isize,
|
|
y: isize,
|
|
deadline: u64,
|
|
) DiffError!ArrayListUnmanaged(Diff) {
|
|
const text1a = text1[0..@intCast(usize, x)];
|
|
const text2a = text2[0..@intCast(usize, y)];
|
|
const text1b = text1[@intCast(usize, x)..];
|
|
const text2b = text2[@intCast(usize, y)..];
|
|
|
|
// Compute both diffs serially.
|
|
var diffs = try dmp.diffInternal(allocator, text1a, text2a, false, deadline);
|
|
var diffsb = try dmp.diffInternal(allocator, text1b, text2b, false, deadline);
|
|
defer diffsb.deinit(allocator);
|
|
|
|
try diffs.appendSlice(allocator, diffsb.items);
|
|
return diffs;
|
|
}
|
|
|
|
//
|
|
// Do a quick line-level diff on both strings, then rediff the parts for
|
|
// greater accuracy.
|
|
// This speedup can produce non-minimal diffs.
|
|
// @param text1 Old string to be diffed.
|
|
// @param text2 New string to be diffed.
|
|
// @param deadline Time when the diff should be complete by.
|
|
// @return List of Diff objects.
|
|
//
|
|
fn diffLineMode(
|
|
dmp: DiffMatchPatch,
|
|
allocator: std.mem.Allocator,
|
|
text1_in: []const u8,
|
|
text2_in: []const u8,
|
|
deadline: u64,
|
|
) DiffError!ArrayListUnmanaged(Diff) {
|
|
// Scan the text on a line-by-line basis first.
|
|
var a = try diffLinesToChars(allocator, text1_in, text2_in);
|
|
var text1 = a.chars_1;
|
|
var text2 = a.chars_2;
|
|
var line_array = a.line_array;
|
|
|
|
var diffs: ArrayListUnmanaged(Diff) = try dmp.diffInternal(allocator, text1, text2, false, deadline);
|
|
|
|
// Convert the diff back to original text.
|
|
try diffCharsToLines(allocator, diffs.items, line_array.items);
|
|
// Eliminate freak matches (e.g. blank lines)
|
|
try diffCleanupSemantic(allocator, &diffs);
|
|
|
|
// Rediff any replacement blocks, this time character-by-character.
|
|
// Add a dummy entry at the end.
|
|
try diffs.append(allocator, Diff{ .operation = .equal, .text = "" });
|
|
|
|
var pointer: usize = 0;
|
|
var count_delete: usize = 0;
|
|
var count_insert: usize = 0;
|
|
var text_delete = ArrayListUnmanaged(u8){};
|
|
var text_insert = ArrayListUnmanaged(u8){};
|
|
defer {
|
|
text_delete.deinit(allocator);
|
|
text_insert.deinit(allocator);
|
|
}
|
|
|
|
while (pointer < diffs.items.len) {
|
|
switch (diffs.items[pointer].operation) {
|
|
.insert => {
|
|
count_insert += 1;
|
|
// text_insert += diffs.items[pointer].text;
|
|
try text_insert.appendSlice(allocator, diffs.items[pointer].text);
|
|
},
|
|
.delete => {
|
|
count_delete += 1;
|
|
// text_delete += diffs.items[pointer].text;
|
|
try text_delete.appendSlice(allocator, diffs.items[pointer].text);
|
|
},
|
|
.equal => {
|
|
// Upon reaching an equality, check for prior redundancies.
|
|
if (count_delete >= 1 and count_insert >= 1) {
|
|
// Delete the offending records and add the merged ones.
|
|
// diffs.RemoveRange(pointer - count_delete - count_insert, count_delete + count_insert);
|
|
try diffs.replaceRange(
|
|
allocator,
|
|
pointer - count_delete - count_insert,
|
|
count_delete + count_insert,
|
|
&.{},
|
|
);
|
|
pointer = pointer - count_delete - count_insert;
|
|
var sub_diff = try dmp.diffInternal(allocator, text_delete.items, text_insert.items, false, deadline);
|
|
// diffs.InsertRange(pointer, sub_diff);
|
|
try diffs.insertSlice(allocator, pointer, sub_diff.items);
|
|
pointer = pointer + sub_diff.items.len;
|
|
}
|
|
count_insert = 0;
|
|
count_delete = 0;
|
|
text_delete.items.len = 0;
|
|
text_insert.items.len = 0;
|
|
},
|
|
}
|
|
pointer += 1;
|
|
}
|
|
// diffs.RemoveAt(diffs.Count - 1); // Remove the dummy entry at the end.
|
|
diffs.items.len -= 1;
|
|
|
|
return diffs;
|
|
}
|
|
|
|
const LinesToCharsResult = struct {
|
|
chars_1: []const u8,
|
|
chars_2: []const u8,
|
|
line_array: ArrayListUnmanaged([]const u8),
|
|
};
|
|
|
|
fn diffLinesToChars(allocator: std.mem.Allocator, text1: []const u8, text2: []const u8) error{OutOfMemory}!LinesToCharsResult {
|
|
var line_array = ArrayListUnmanaged([]const u8){};
|
|
var line_hash = std.StringHashMapUnmanaged(usize){};
|
|
// e.g. line_array[4] == "Hello\n"
|
|
// e.g. line_hash.get("Hello\n") == 4
|
|
|
|
// "\x00" is a valid character, but various debuggers don't like it.
|
|
// So we'll insert a junk entry to avoid generating a null character.
|
|
try line_array.append(allocator, "");
|
|
|
|
// Allocate 2/3rds of the space for text1, the rest for text2.
|
|
var chars1 = try diffLinesToCharsMunge(allocator, text1, &line_array, &line_hash, 40000);
|
|
var chars2 = try diffLinesToCharsMunge(allocator, text2, &line_array, &line_hash, 65535);
|
|
return .{ .chars_1 = chars1, .chars_2 = chars2, .line_array = line_array };
|
|
}
|
|
|
|
fn diffLinesToCharsMunge(
|
|
allocator: std.mem.Allocator,
|
|
text: []const u8,
|
|
line_array: *ArrayListUnmanaged([]const u8),
|
|
line_hash: *std.StringHashMapUnmanaged(usize),
|
|
max_lines: usize,
|
|
) error{OutOfMemory}![]const u8 {
|
|
var line_start: isize = 0;
|
|
var line_end: isize = -1;
|
|
var line: []const u8 = "";
|
|
var chars = ArrayListUnmanaged(u8){};
|
|
// Walk the text, pulling out a Substring for each line.
|
|
// text.split('\n') would would temporarily double our memory footprint.
|
|
// Modifying text would create many large strings to garbage collect.
|
|
while (line_end < @intCast(isize, text.len) - 1) {
|
|
line_end = b: {
|
|
break :b @intCast(isize, std.mem.indexOf(u8, text[@intCast(usize, line_start)..], "\n") orelse break :b @intCast(isize, text.len - 1)) + line_start;
|
|
};
|
|
line = text[@intCast(usize, line_start) .. @intCast(usize, line_start) + @intCast(usize, line_end + 1 - line_start)];
|
|
|
|
if (line_hash.get(line)) |value| {
|
|
try chars.append(allocator, @intCast(u8, value));
|
|
} else {
|
|
if (line_array.items.len == max_lines) {
|
|
// Bail out at 65535 because char 65536 == char 0.
|
|
line = text[@intCast(usize, line_start)..];
|
|
line_end = @intCast(isize, text.len);
|
|
}
|
|
try line_array.append(allocator, line);
|
|
try line_hash.put(allocator, line, line_array.items.len - 1);
|
|
try chars.append(allocator, @intCast(u8, line_array.items.len - 1));
|
|
}
|
|
line_start = line_end + 1;
|
|
}
|
|
return try chars.toOwnedSlice(allocator);
|
|
}
|
|
|
|
fn diffCharsToLines(allocator: std.mem.Allocator, diffs: []Diff, line_array: []const []const u8) error{OutOfMemory}!void {
|
|
var text = ArrayListUnmanaged(u8){};
|
|
defer text.deinit(allocator);
|
|
|
|
for (diffs) |*d| {
|
|
text.items.len = 0;
|
|
var j: usize = 0;
|
|
while (j < d.text.len) : (j += 1) {
|
|
try text.appendSlice(allocator, line_array[d.text[j]]);
|
|
}
|
|
d.text = try allocator.dupe(u8, text.items);
|
|
}
|
|
}
|
|
|
|
//
|
|
// Reorder and merge like edit sections. Merge equalities.
|
|
// Any edit section can move as long as it doesn't cross an equality.
|
|
// @param diffs List of Diff objects.
|
|
//
|
|
fn diffCleanupMerge(allocator: std.mem.Allocator, diffs: *std.ArrayListUnmanaged(Diff)) error{OutOfMemory}!void {
|
|
// Add a dummy entry at the end.
|
|
try diffs.append(allocator, Diff{ .operation = .equal, .text = "" });
|
|
var pointer: usize = 0;
|
|
var count_delete: usize = 0;
|
|
var count_insert: usize = 0;
|
|
|
|
var text_delete = ArrayListUnmanaged(u8){};
|
|
defer text_delete.deinit(allocator);
|
|
|
|
var text_insert = ArrayListUnmanaged(u8){};
|
|
defer text_insert.deinit(allocator);
|
|
|
|
var common_length: usize = undefined;
|
|
while (pointer < diffs.items.len) {
|
|
switch (diffs.items[pointer].operation) {
|
|
.insert => {
|
|
count_insert += 1;
|
|
try text_insert.appendSlice(allocator, diffs.items[pointer].text);
|
|
pointer += 1;
|
|
},
|
|
.delete => {
|
|
count_delete += 1;
|
|
try text_delete.appendSlice(allocator, diffs.items[pointer].text);
|
|
pointer += 1;
|
|
},
|
|
.equal => {
|
|
// Upon reaching an equality, check for prior redundancies.
|
|
if (count_delete + count_insert > 1) {
|
|
if (count_delete != 0 and count_insert != 0) {
|
|
// Factor out any common prefixies.
|
|
common_length = diffCommonPrefix(text_insert.items, text_delete.items);
|
|
if (common_length != 0) {
|
|
if ((pointer - count_delete - count_insert) > 0 and
|
|
diffs.items[pointer - count_delete - count_insert - 1].operation == .equal)
|
|
{
|
|
// diffs.items[pointer - count_delete - count_insert - 1].text
|
|
// += text_insert.Substring(0, common_length);
|
|
|
|
const ii = pointer - count_delete - count_insert - 1;
|
|
var nt = try allocator.alloc(u8, diffs.items[ii].text.len + common_length);
|
|
|
|
// try diffs.items[pointer - count_delete - count_insert - 1].text.append(allocator, text_insert.items[0..common_length]);
|
|
std.mem.copy(u8, nt, diffs.items[ii].text);
|
|
std.mem.copy(u8, nt[diffs.items[ii].text.len..], text_insert.items[0..common_length]);
|
|
|
|
allocator.free(diffs.items[ii].text);
|
|
diffs.items[ii].text = nt;
|
|
} else {
|
|
// diffs.Insert(0, new Diff(Operation.EQUAL,
|
|
// text_insert.Substring(0, common_length)));
|
|
const text = std.ArrayListUnmanaged(u8){ .items = try allocator.dupe(u8, text_insert.items[0..common_length]) };
|
|
try diffs.insert(allocator, 0, Diff{ .operation = .equal, .text = try allocator.dupe(u8, text.items) });
|
|
pointer += 1;
|
|
}
|
|
try text_insert.replaceRange(allocator, 0, common_length, &.{});
|
|
try text_delete.replaceRange(allocator, 0, common_length, &.{});
|
|
}
|
|
// Factor out any common suffixies.
|
|
// @ZigPort this seems very wrong
|
|
common_length = diffCommonSuffix(text_insert.items, text_delete.items);
|
|
if (common_length != 0) {
|
|
diffs.items[pointer].text = try std.mem.concat(allocator, u8, &.{ text_insert.items[text_insert.items.len - common_length ..], diffs.items[pointer].text });
|
|
text_insert.items.len -= common_length;
|
|
text_delete.items.len -= common_length;
|
|
}
|
|
}
|
|
// Delete the offending records and add the merged ones.
|
|
pointer -= count_delete + count_insert;
|
|
try diffs.replaceRange(allocator, pointer, count_delete + count_insert, &.{});
|
|
|
|
if (text_delete.items.len != 0) {
|
|
try diffs.replaceRange(allocator, pointer, 0, &.{Diff{ .operation = .delete, .text = try allocator.dupe(u8, text_delete.items) }});
|
|
pointer += 1;
|
|
}
|
|
if (text_insert.items.len != 0) {
|
|
try diffs.replaceRange(allocator, pointer, 0, &.{Diff{ .operation = .insert, .text = try allocator.dupe(u8, text_insert.items) }});
|
|
pointer += 1;
|
|
}
|
|
pointer += 1;
|
|
} else if (pointer != 0 and diffs.items[pointer - 1].operation == .equal) {
|
|
// Merge this equality with the previous one.
|
|
// TODO: Fix using realloc or smth
|
|
|
|
var nt = try allocator.alloc(u8, diffs.items[pointer - 1].text.len + diffs.items[pointer].text.len);
|
|
|
|
// try diffs.items[pointer - count_delete - count_insert - 1].text.append(allocator, text_insert.items[0..common_length]);
|
|
std.mem.copy(u8, nt, diffs.items[pointer - 1].text);
|
|
std.mem.copy(u8, nt[diffs.items[pointer - 1].text.len..], diffs.items[pointer].text);
|
|
|
|
// allocator.free(diffs.items[pointer - 1].text);
|
|
diffs.items[pointer - 1].text = nt;
|
|
// allocator.free(diffs.items[pointer].text);
|
|
|
|
// try diffs.items[pointer - 1].text.append(allocator, diffs.items[pointer].text.items);
|
|
_ = diffs.orderedRemove(pointer);
|
|
} else {
|
|
pointer += 1;
|
|
}
|
|
count_insert = 0;
|
|
count_delete = 0;
|
|
text_delete.items.len = 0;
|
|
text_insert.items.len = 0;
|
|
},
|
|
}
|
|
}
|
|
if (diffs.items[diffs.items.len - 1].text.len == 0) {
|
|
diffs.items.len -= 1;
|
|
}
|
|
|
|
// Second pass: look for single edits surrounded on both sides by
|
|
// equalities which can be shifted sideways to eliminate an equality.
|
|
// e.g: A<ins>BA</ins>C -> <ins>AB</ins>AC
|
|
var changes = false;
|
|
pointer = 1;
|
|
// Intentionally ignore the first and last element (don't need checking).
|
|
while (pointer < (diffs.items.len - 1)) {
|
|
if (diffs.items[pointer - 1].operation == .equal and
|
|
diffs.items[pointer + 1].operation == .equal)
|
|
{
|
|
// This is a single edit surrounded by equalities.
|
|
if (std.mem.endsWith(u8, diffs.items[pointer].text, diffs.items[pointer - 1].text)) {
|
|
// Shift the edit over the previous equality.
|
|
// diffs.items[pointer].text = diffs.items[pointer - 1].text +
|
|
// diffs.items[pointer].text[0 .. diffs.items[pointer].text.len -
|
|
// diffs.items[pointer - 1].text.len];
|
|
// diffs.items[pointer + 1].text = diffs.items[pointer - 1].text + diffs.items[pointer + 1].text;
|
|
|
|
const pt = try std.mem.concat(allocator, u8, &.{
|
|
diffs.items[pointer - 1].text,
|
|
diffs.items[pointer].text[0 .. diffs.items[pointer].text.len -
|
|
diffs.items[pointer - 1].text.len],
|
|
});
|
|
const p1t = try std.mem.concat(allocator, u8, &.{ diffs.items[pointer - 1].text, diffs.items[pointer + 1].text });
|
|
|
|
// allocator.free(diffs.items[pointer].text);
|
|
// allocator.free(diffs.items[pointer + 1].text);
|
|
|
|
diffs.items[pointer].text = pt;
|
|
diffs.items[pointer + 1].text = p1t;
|
|
|
|
try diffs.replaceRange(allocator, pointer - 1, 1, &.{});
|
|
changes = true;
|
|
} else if (std.mem.startsWith(u8, diffs.items[pointer].text, diffs.items[pointer + 1].text)) {
|
|
// Shift the edit over the next equality.
|
|
// diffs.items[pointer - 1].text += diffs.items[pointer + 1].text;
|
|
// diffs.items[pointer].text =
|
|
// diffs.items[pointer].text[diffs.items[pointer + 1].text.len..] + diffs.items[pointer + 1].text;
|
|
|
|
const pm1t = try std.mem.concat(allocator, u8, &.{ diffs.items[pointer - 1].text, diffs.items[pointer + 1].text });
|
|
const pt = try std.mem.concat(allocator, u8, &.{
|
|
diffs.items[pointer].text[diffs.items[pointer + 1].text.len..],
|
|
diffs.items[pointer + 1].text,
|
|
});
|
|
|
|
// allocator.free(diffs.items[pointer - 1].text);
|
|
// allocator.free(diffs.items[pointer].text);
|
|
|
|
diffs.items[pointer - 1].text = pm1t;
|
|
diffs.items[pointer].text = pt;
|
|
|
|
try diffs.replaceRange(allocator, pointer + 1, 1, &.{});
|
|
changes = true;
|
|
}
|
|
}
|
|
pointer += 1;
|
|
}
|
|
// If shifts were made, the diff needs reordering and another shift sweep.
|
|
if (changes) {
|
|
try diffCleanupMerge(allocator, diffs);
|
|
}
|
|
}
|
|
|
|
fn diffCleanupSemantic(allocator: std.mem.Allocator, diffs: *ArrayListUnmanaged(Diff)) error{OutOfMemory}!void {
|
|
var changes = false;
|
|
// Stack of indices where equalities are found.
|
|
var equalities = ArrayListUnmanaged(isize){};
|
|
// Always equal to equalities[equalitiesLength-1][1]
|
|
var last_equality: ?[]const u8 = null;
|
|
var pointer: isize = 0; // Index of current position.
|
|
// Number of characters that changed prior to the equality.
|
|
var length_insertions1: usize = 0;
|
|
var length_deletions1: usize = 0;
|
|
// Number of characters that changed after the equality.
|
|
var length_insertions2: usize = 0;
|
|
var length_deletions2: usize = 0;
|
|
while (pointer < diffs.items.len) {
|
|
if (diffs.items[@intCast(usize, pointer)].operation == .equal) { // Equality found.
|
|
try equalities.append(allocator, pointer);
|
|
length_insertions1 = length_insertions2;
|
|
length_deletions1 = length_deletions2;
|
|
length_insertions2 = 0;
|
|
length_deletions2 = 0;
|
|
last_equality = diffs.items[@intCast(usize, pointer)].text;
|
|
} else { // an insertion or deletion
|
|
if (diffs.items[@intCast(usize, pointer)].operation == .equal) {
|
|
length_insertions2 += diffs.items[@intCast(usize, pointer)].text.len;
|
|
} else {
|
|
length_deletions2 += diffs.items[@intCast(usize, pointer)].text.len;
|
|
}
|
|
// Eliminate an equality that is smaller or equal to the edits on both
|
|
// sides of it.
|
|
if (last_equality != null and (last_equality.?.len <= std.math.max(length_insertions1, length_deletions1)) and (last_equality.?.len <= std.math.max(length_insertions2, length_deletions2))) {
|
|
// Duplicate record.
|
|
try diffs.insert(allocator, @intCast(usize, equalities.items[equalities.items.len - 1]), Diff{ .operation = .delete, .text = last_equality.? });
|
|
// Change second copy to insert.
|
|
diffs.items[@intCast(usize, equalities.items[equalities.items.len - 1] + 1)].operation = .insert;
|
|
// Throw away the equality we just deleted.
|
|
_ = equalities.pop();
|
|
if (equalities.items.len > 0) {
|
|
_ = equalities.pop();
|
|
}
|
|
pointer = if (equalities.items.len > 0) equalities.items[equalities.items.len - 1] else -1;
|
|
length_insertions1 = 0; // Reset the counters.
|
|
length_deletions1 = 0;
|
|
length_insertions2 = 0;
|
|
length_deletions2 = 0;
|
|
last_equality = null;
|
|
changes = true;
|
|
}
|
|
}
|
|
pointer += 1;
|
|
}
|
|
|
|
// Normalize the diff.
|
|
if (changes) {
|
|
try diffCleanupMerge(allocator, diffs);
|
|
}
|
|
try diffCleanupSemanticLossless(allocator, diffs);
|
|
|
|
// Find any overlaps between deletions and insertions.
|
|
// e.g: <del>abcxxx</del><ins>xxxdef</ins>
|
|
// -> <del>abc</del>xxx<ins>def</ins>
|
|
// e.g: <del>xxxabc</del><ins>defxxx</ins>
|
|
// -> <ins>def</ins>xxx<del>abc</del>
|
|
// Only extract an overlap if it is as big as the edit ahead or behind it.
|
|
pointer = 1;
|
|
while (pointer < diffs.items.len) {
|
|
if (diffs.items[@intCast(usize, pointer - 1)].operation == .delete and
|
|
diffs.items[@intCast(usize, pointer)].operation == .insert)
|
|
{
|
|
const deletion = diffs.items[@intCast(usize, pointer - 1)].text;
|
|
const insertion = diffs.items[@intCast(usize, pointer)].text;
|
|
var overlap_length1: usize = diffCommonOverlap(deletion, insertion);
|
|
var overlap_length2: usize = diffCommonOverlap(insertion, deletion);
|
|
if (overlap_length1 >= overlap_length2) {
|
|
if (@intToFloat(f32, overlap_length1) >= @intToFloat(f32, deletion.len) / 2.0 or
|
|
@intToFloat(f32, overlap_length1) >= @intToFloat(f32, insertion.len) / 2.0)
|
|
{
|
|
// Overlap found.
|
|
// Insert an equality and trim the surrounding edits.
|
|
try diffs.insert(allocator, @intCast(usize, pointer), Diff{ .operation = .equal, .text = try allocator.dupe(u8, insertion[0..overlap_length1]) });
|
|
diffs.items[@intCast(usize, pointer - 1)].text = try allocator.dupe(u8, deletion[0 .. deletion.len - overlap_length1]);
|
|
diffs.items[@intCast(usize, pointer + 1)].text = try allocator.dupe(u8, insertion[overlap_length1..]);
|
|
pointer += 1;
|
|
}
|
|
} else {
|
|
if (@intToFloat(f32, overlap_length2) >= @intToFloat(f32, deletion.len) / 2.0 or
|
|
@intToFloat(f32, overlap_length2) >= @intToFloat(f32, insertion.len) / 2.0)
|
|
{
|
|
// Reverse overlap found.
|
|
// Insert an equality and swap and trim the surrounding edits.
|
|
try diffs.insert(allocator, @intCast(usize, pointer), Diff{ .operation = .equal, .text = try allocator.dupe(u8, deletion[0..overlap_length2]) });
|
|
diffs.items[@intCast(usize, pointer - 1)].operation = .insert;
|
|
diffs.items[@intCast(usize, pointer - 1)].text = try allocator.dupe(u8, insertion[0 .. insertion.len - overlap_length2]);
|
|
diffs.items[@intCast(usize, pointer + 1)].operation = .delete;
|
|
diffs.items[@intCast(usize, pointer + 1)].text = try allocator.dupe(u8, deletion[overlap_length2..]);
|
|
pointer += 1;
|
|
}
|
|
}
|
|
pointer += 1;
|
|
}
|
|
pointer += 1;
|
|
}
|
|
}
|
|
|
|
/// Look for single edits surrounded on both sides by equalities
|
|
/// which can be shifted sideways to align the edit to a word boundary.
|
|
/// e.g: The c<ins>at c</ins>ame. -> The <ins>cat </ins>came.
|
|
pub fn diffCleanupSemanticLossless(
|
|
allocator: std.mem.Allocator,
|
|
diffs: *ArrayListUnmanaged(Diff),
|
|
) error{OutOfMemory}!void {
|
|
var pointer: usize = 1;
|
|
// Intentionally ignore the first and last element (don't need checking).
|
|
while (pointer < diffs.items.len - 1) {
|
|
if (diffs.items[pointer - 1].operation == .equal and
|
|
diffs.items[pointer + 1].operation == .equal)
|
|
{
|
|
// This is a single edit surrounded by equalities.
|
|
var equality_1 = std.ArrayListUnmanaged(u8){};
|
|
defer equality_1.deinit(allocator);
|
|
try equality_1.appendSlice(allocator, diffs.items[pointer - 1].text);
|
|
|
|
var edit = std.ArrayListUnmanaged(u8){};
|
|
defer edit.deinit(allocator);
|
|
try edit.appendSlice(allocator, diffs.items[pointer].text);
|
|
|
|
var equality_2 = std.ArrayListUnmanaged(u8){};
|
|
defer equality_2.deinit(allocator);
|
|
try equality_2.appendSlice(allocator, diffs.items[pointer + 1].text);
|
|
|
|
// First, shift the edit as far left as possible.
|
|
const common_offset = diffCommonSuffix(equality_1.items, edit.items);
|
|
if (common_offset > 0) {
|
|
// TODO: Use buffer
|
|
const common_string = try allocator.dupe(u8, edit.items[edit.items.len - common_offset ..]);
|
|
defer allocator.free(common_string);
|
|
|
|
equality_1.items.len = equality_1.items.len - common_offset;
|
|
|
|
edit.items.len = edit.items.len - common_offset;
|
|
try edit.insertSlice(allocator, 0, common_string);
|
|
|
|
try equality_2.insertSlice(allocator, 0, common_string);
|
|
}
|
|
|
|
// Second, step character by character right,
|
|
// looking for the best fit.
|
|
var best_equality_1 = ArrayListUnmanaged(u8){};
|
|
defer best_equality_1.deinit(allocator);
|
|
try best_equality_1.appendSlice(allocator, equality_1.items);
|
|
|
|
var best_edit = ArrayListUnmanaged(u8){};
|
|
defer best_edit.deinit(allocator);
|
|
try best_edit.appendSlice(allocator, edit.items);
|
|
|
|
var best_equality_2 = ArrayListUnmanaged(u8){};
|
|
defer best_equality_2.deinit(allocator);
|
|
try best_equality_2.appendSlice(allocator, equality_2.items);
|
|
|
|
var best_score = diffCleanupSemanticScore(equality_1.items, edit.items) +
|
|
diffCleanupSemanticScore(edit.items, equality_2.items);
|
|
|
|
while (edit.items.len != 0 and equality_2.items.len != 0 and edit.items[0] == equality_2.items[0]) {
|
|
try equality_1.append(allocator, edit.items[0]);
|
|
|
|
_ = edit.orderedRemove(0);
|
|
try edit.append(allocator, equality_2.items[0]);
|
|
|
|
_ = equality_2.orderedRemove(0);
|
|
|
|
const score = diffCleanupSemanticScore(equality_1.items, edit.items) +
|
|
diffCleanupSemanticScore(edit.items, equality_2.items);
|
|
// The >= encourages trailing rather than leading whitespace on
|
|
// edits.
|
|
if (score >= best_score) {
|
|
best_score = score;
|
|
|
|
best_equality_1.items.len = 0;
|
|
try best_equality_1.appendSlice(allocator, equality_1.items);
|
|
|
|
best_edit.items.len = 0;
|
|
try best_edit.appendSlice(allocator, edit.items);
|
|
|
|
best_equality_2.items.len = 0;
|
|
try best_equality_2.appendSlice(allocator, equality_2.items);
|
|
}
|
|
}
|
|
|
|
if (!std.mem.eql(u8, diffs.items[pointer - 1].text, best_equality_1.items)) {
|
|
// We have an improvement, save it back to the diff.
|
|
if (best_equality_1.items.len != 0) {
|
|
diffs.items[pointer - 1].text = try allocator.dupe(u8, best_equality_1.items);
|
|
} else {
|
|
_ = diffs.orderedRemove(pointer - 1);
|
|
pointer -= 1;
|
|
}
|
|
diffs.items[pointer].text = try allocator.dupe(u8, best_edit.items);
|
|
if (best_equality_2.items.len != 0) {
|
|
diffs.items[pointer + 1].text = try allocator.dupe(u8, best_equality_2.items);
|
|
} else {
|
|
_ = diffs.orderedRemove(pointer + 1);
|
|
pointer -= 1;
|
|
}
|
|
}
|
|
}
|
|
pointer += 1;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Given two strings, compute a score representing whether the internal
|
|
// boundary falls on logical boundaries.
|
|
// Scores range from 6 (best) to 0 (worst).
|
|
// @param one First string.
|
|
// @param two Second string.
|
|
// @return The score.
|
|
//
|
|
fn diffCleanupSemanticScore(one: []const u8, two: []const u8) usize {
|
|
if (one.len == 0 or two.len == 0) {
|
|
// Edges are the best.
|
|
return 6;
|
|
}
|
|
|
|
// Each port of this function behaves slightly differently due to
|
|
// subtle differences in each language's definition of things like
|
|
// 'whitespace'. Since this function's purpose is largely cosmetic,
|
|
// the choice has been made to use each language's native features
|
|
// rather than force total conformity.
|
|
const char1 = one[one.len - 1];
|
|
const char2 = two[0];
|
|
const nonAlphaNumeric1 = !std.ascii.isAlphanumeric(char1);
|
|
const nonAlphaNumeric2 = !std.ascii.isAlphanumeric(char2);
|
|
const whitespace1 = nonAlphaNumeric1 and std.ascii.isWhitespace(char1);
|
|
const whitespace2 = nonAlphaNumeric2 and std.ascii.isWhitespace(char2);
|
|
const lineBreak1 = whitespace1 and std.ascii.isControl(char1);
|
|
const lineBreak2 = whitespace2 and std.ascii.isControl(char2);
|
|
const blankLine1 = lineBreak1 and
|
|
// BLANKLINEEND.IsMatch(one);
|
|
(std.mem.endsWith(u8, one, "\n") or std.mem.endsWith(u8, one, "\r\n"));
|
|
const blankLine2 = lineBreak2 and
|
|
// BLANKLINESTART.IsMatch(two);
|
|
(std.mem.startsWith(u8, two, "\n") or std.mem.startsWith(u8, two, "\r\n"));
|
|
|
|
if (blankLine1 or blankLine2) {
|
|
// Five points for blank lines.
|
|
return 5;
|
|
} else if (lineBreak1 or lineBreak2) {
|
|
// Four points for line breaks.
|
|
return 4;
|
|
} else if (nonAlphaNumeric1 and !whitespace1 and whitespace2) {
|
|
// Three points for end of sentences.
|
|
return 3;
|
|
} else if (whitespace1 or whitespace2) {
|
|
// Two points for whitespace.
|
|
return 2;
|
|
} else if (nonAlphaNumeric1 or nonAlphaNumeric2) {
|
|
// One point for non-alphanumeric.
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// Define some regex patterns for matching boundaries.
|
|
// private Regex BLANKLINEEND = new Regex("\\n\\r?\\n\\Z");
|
|
// private Regex BLANKLINESTART = new Regex("\\A\\r?\\n\\r?\\n");
|
|
|
|
/// Reduce the number of edits by eliminating operationally trivial
|
|
/// equalities.
|
|
pub fn diffCleanupEfficiency(
|
|
dmp: DiffMatchPatch,
|
|
allocator: std.mem.Allocator,
|
|
diffs: *ArrayListUnmanaged(Diff),
|
|
) error{OutOfMemory}!void {
|
|
var changes = false;
|
|
// Stack of indices where equalities are found.
|
|
var equalities = ArrayListUnmanaged(Diff){};
|
|
// Always equal to equalities[equalitiesLength-1][1]
|
|
var last_equality = "";
|
|
var pointer: isize = 0; // Index of current position.
|
|
// Is there an insertion operation before the last equality.
|
|
var pre_ins = false;
|
|
// Is there a deletion operation before the last equality.
|
|
var pre_del = false;
|
|
// Is there an insertion operation after the last equality.
|
|
var post_ins = false;
|
|
// Is there a deletion operation after the last equality.
|
|
var post_del = false;
|
|
while (pointer < diffs.Count) {
|
|
if (diffs.items[pointer].operation == .equal) { // Equality found.
|
|
if (diffs.items[pointer].text.len < dmp.diff_edit_cost and (post_ins or post_del)) {
|
|
// Candidate found.
|
|
equalities.Push(pointer);
|
|
pre_ins = post_ins;
|
|
pre_del = post_del;
|
|
last_equality = diffs.items[pointer].text;
|
|
} else {
|
|
// Not a candidate, and can never become one.
|
|
equalities.items.len = 0;
|
|
last_equality = "";
|
|
}
|
|
post_ins = false;
|
|
post_del = false;
|
|
} else { // An insertion or deletion.
|
|
if (diffs.items[pointer].operation == .delete) {
|
|
post_del = true;
|
|
} else {
|
|
post_ins = true;
|
|
}
|
|
// Five types to be split:
|
|
// <ins>A</ins><del>B</del>XY<ins>C</ins><del>D</del>
|
|
// <ins>A</ins>X<ins>C</ins><del>D</del>
|
|
// <ins>A</ins><del>B</del>X<ins>C</ins>
|
|
// <ins>A</del>X<ins>C</ins><del>D</del>
|
|
// <ins>A</ins><del>B</del>X<del>C</del>
|
|
if ((last_equality.Length != 0) and ((pre_ins and pre_del and post_ins and post_del) or ((last_equality.Length < dmp.diff_edit_cost / 2) and ((if (pre_ins) 1 else 0) + (if (pre_del) 1 else 0) + (if (post_ins) 1 else 0) + (if (post_del) 1 else 0)) == 3))) {
|
|
// Duplicate record.
|
|
try diffs.insert(
|
|
allocator,
|
|
equalities.items[equalities.items.len - 1],
|
|
Diff{ .operation = .delete, .text = try allocator.dupe(u8, last_equality) },
|
|
);
|
|
// Change second copy to insert.
|
|
diffs.items[equalities.items[equalities.items.len - 1] + 1].operation = .insert;
|
|
_ = equalities.pop(); // Throw away the equality we just deleted.
|
|
last_equality = "";
|
|
if (pre_ins and pre_del) {
|
|
// No changes made which could affect previous entry, keep going.
|
|
post_ins = true;
|
|
post_del = true;
|
|
equalities.items.len = 0;
|
|
} else {
|
|
if (equalities.items.len > 0) {
|
|
_ = equalities.pop();
|
|
}
|
|
|
|
pointer = if (equalities.items.len > 0) equalities.items[equalities.items.len - 1] else -1;
|
|
post_ins = false;
|
|
post_del = false;
|
|
}
|
|
changes = true;
|
|
}
|
|
}
|
|
pointer += 1;
|
|
}
|
|
|
|
if (changes) {
|
|
try diffCleanupMerge(allocator, diffs);
|
|
}
|
|
}
|
|
|
|
//
|
|
// Determine if the suffix of one string is the prefix of another.
|
|
// @param text1 First string.
|
|
// @param text2 Second string.
|
|
// @return The number of characters common to the end of the first
|
|
// string and the start of the second string.
|
|
//
|
|
fn diffCommonOverlap(text1_in: []const u8, text2_in: []const u8) usize {
|
|
var text1 = text1_in;
|
|
var text2 = text2_in;
|
|
|
|
// Cache the text lengths to prevent multiple calls.
|
|
var text1_length = text1.len;
|
|
var text2_length = text2.len;
|
|
// Eliminate the null case.
|
|
if (text1_length == 0 or text2_length == 0) {
|
|
return 0;
|
|
}
|
|
// Truncate the longer string.
|
|
if (text1_length > text2_length) {
|
|
text1 = text1[text1_length - text2_length ..];
|
|
} else if (text1_length < text2_length) {
|
|
text2 = text2[0..text1_length];
|
|
}
|
|
const text_length = @min(text1_length, text2_length);
|
|
// Quick check for the worst case.
|
|
if (std.mem.eql(u8, text1, text2)) {
|
|
return text_length;
|
|
}
|
|
|
|
// Start by looking for a single character match
|
|
// and increase length until no match is found.
|
|
// Performance analysis: https://neil.fraser.name/news/2010/11/04/
|
|
var best: usize = 0;
|
|
var length: usize = 1;
|
|
while (true) {
|
|
const pattern = text1[text_length - length ..];
|
|
const found = std.mem.indexOf(u8, text2, pattern) orelse
|
|
return best;
|
|
|
|
length += found;
|
|
|
|
if (found == 0 or std.mem.eql(u8, text1[text_length - length ..], text2[0..length])) {
|
|
best = length;
|
|
length += 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
// pub fn main() void {
|
|
// var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
|
|
// defer arena.deinit();
|
|
|
|
// var bruh = default.diff(arena.allocator(), "Hello World.", "Goodbye World.", true);
|
|
// std.log.err("{any}", .{bruh});
|
|
// }
|
|
|
|
// test {
|
|
// var arena = std.heap.ArenaAllocator.init(testing.allocator);
|
|
// defer arena.deinit();
|
|
|
|
// var bruh = try default.diff(arena.allocator(), "Hello World.", "Goodbye World.", true);
|
|
// try diffCleanupSemantic(arena.allocator(), &bruh);
|
|
// for (bruh.items) |b| {
|
|
// std.log.err("{any}", .{b});
|
|
// }
|
|
|
|
// // for (bruh.items) |b| {
|
|
// // std.log.err("{s} {s}", .{ switch (b.operation) {
|
|
// // .equal => "",
|
|
// // .insert => "+",
|
|
// // .delete => "-",
|
|
// // }, b.text });
|
|
// // }
|
|
// }
|
|
|
|
test diffCommonPrefix {
|
|
// Detect any common suffix.
|
|
try testing.expectEqual(@as(usize, 0), diffCommonPrefix("abc", "xyz")); // Null case
|
|
try testing.expectEqual(@as(usize, 4), diffCommonPrefix("1234abcdef", "1234xyz")); // Non-null case
|
|
try testing.expectEqual(@as(usize, 4), diffCommonPrefix("1234", "1234xyz")); // Whole case
|
|
}
|
|
|
|
test diffCommonSuffix {
|
|
// Detect any common suffix.
|
|
try testing.expectEqual(@as(usize, 0), diffCommonSuffix("abc", "xyz")); // Null case
|
|
try testing.expectEqual(@as(usize, 4), diffCommonSuffix("abcdef1234", "xyz1234")); // Non-null case
|
|
try testing.expectEqual(@as(usize, 4), diffCommonSuffix("1234", "xyz1234")); // Whole case
|
|
}
|
|
|
|
test diffCommonOverlap {
|
|
// Detect any suffix/prefix overlap.
|
|
try testing.expectEqual(@as(usize, 0), diffCommonOverlap("", "abcd")); // Null case
|
|
try testing.expectEqual(@as(usize, 3), diffCommonOverlap("abc", "abcd")); // Whole case
|
|
try testing.expectEqual(@as(usize, 0), diffCommonOverlap("123456", "abcd")); // No overlap
|
|
try testing.expectEqual(@as(usize, 3), diffCommonOverlap("123456xxx", "xxxabcd")); // Overlap
|
|
|
|
// Some overly clever languages (C#) may treat ligatures as equal to their
|
|
// component letters. E.g. U+FB01 == 'fi'
|
|
try testing.expectEqual(@as(usize, 0), diffCommonOverlap("fi", "\u{fb01}")); // Unicode
|
|
}
|
|
|
|
test diffHalfMatch {
|
|
var arena = std.heap.ArenaAllocator.init(testing.allocator);
|
|
defer arena.deinit();
|
|
|
|
var one_timeout = DiffMatchPatch{};
|
|
one_timeout.diff_timeout = 1;
|
|
|
|
try testing.expectEqual(@as(?HalfMatchResult, null), try one_timeout.diffHalfMatch(arena.allocator(), "1234567890", "abcdef")); // No match #1
|
|
try testing.expectEqual(@as(?HalfMatchResult, null), try one_timeout.diffHalfMatch(arena.allocator(), "12345", "23")); // No match #2
|
|
|
|
// Single matches
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "12",
|
|
.suffix_before = "90",
|
|
.prefix_after = "a",
|
|
.suffix_after = "z",
|
|
.common_middle = "345678",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "1234567890", "a345678z")); // Single Match #1
|
|
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "a",
|
|
.suffix_before = "z",
|
|
.prefix_after = "12",
|
|
.suffix_after = "90",
|
|
.common_middle = "345678",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "a345678z", "1234567890")); // Single Match #2
|
|
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "abc",
|
|
.suffix_before = "z",
|
|
.prefix_after = "1234",
|
|
.suffix_after = "0",
|
|
.common_middle = "56789",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "abc56789z", "1234567890")); // Single Match #3
|
|
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "a",
|
|
.suffix_before = "xyz",
|
|
.prefix_after = "1",
|
|
.suffix_after = "7890",
|
|
.common_middle = "23456",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "a23456xyz", "1234567890")); // Single Match #4
|
|
|
|
// Multiple matches
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "12123",
|
|
.suffix_before = "123121",
|
|
.prefix_after = "a",
|
|
.suffix_after = "z",
|
|
.common_middle = "1234123451234",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "121231234123451234123121", "a1234123451234z")); // Multiple Matches #1
|
|
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "",
|
|
.suffix_before = "-=-=-=-=-=",
|
|
.prefix_after = "x",
|
|
.suffix_after = "",
|
|
.common_middle = "x-=-=-=-=-=-=-=",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "x-=-=-=-=-=-=-=-=-=-=-=-=", "xx-=-=-=-=-=-=-=")); // Multiple Matches #2
|
|
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "-=-=-=-=-=",
|
|
.suffix_before = "",
|
|
.prefix_after = "",
|
|
.suffix_after = "y",
|
|
.common_middle = "-=-=-=-=-=-=-=y",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "-=-=-=-=-=-=-=-=-=-=-=-=y", "-=-=-=-=-=-=-=yy")); // Multiple Matches #3
|
|
|
|
// Other cases
|
|
// Optimal diff would be -q+x=H-i+e=lloHe+Hu=llo-Hew+y not -qHillo+x=HelloHe-w+Hulloy
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, HalfMatchResult{
|
|
.prefix_before = "qHillo",
|
|
.suffix_before = "w",
|
|
.prefix_after = "x",
|
|
.suffix_after = "Hulloy",
|
|
.common_middle = "HelloHe",
|
|
}), try one_timeout.diffHalfMatch(arena.allocator(), "qHilloHelloHew", "xHelloHeHulloy")); // Non-optimal halfmatch
|
|
|
|
one_timeout.diff_timeout = 0;
|
|
try testing.expectEqualDeep(@as(?HalfMatchResult, null), try one_timeout.diffHalfMatch(arena.allocator(), "qHilloHelloHew", "xHelloHeHulloy")); // Non-optimal halfmatch
|
|
}
|
|
|
|
test diffLinesToChars {
|
|
var arena = std.heap.ArenaAllocator.init(testing.allocator);
|
|
defer arena.deinit();
|
|
|
|
// Convert lines down to characters.
|
|
var tmp_array_list = std.ArrayList([]const u8).init(arena.allocator());
|
|
try tmp_array_list.append("");
|
|
try tmp_array_list.append("alpha\n");
|
|
try tmp_array_list.append("beta\n");
|
|
|
|
var result = try diffLinesToChars(arena.allocator(), "alpha\nbeta\nalpha\n", "beta\nalpha\nbeta\n");
|
|
try testing.expectEqualStrings("\u{0001}\u{0002}\u{0001}", result.chars_1); // Shared lines #1
|
|
try testing.expectEqualStrings("\u{0002}\u{0001}\u{0002}", result.chars_2); // Shared lines #2
|
|
try testing.expectEqualDeep(tmp_array_list.items, result.line_array.items); // Shared lines #3
|
|
|
|
tmp_array_list.items.len = 0;
|
|
try tmp_array_list.append("");
|
|
try tmp_array_list.append("alpha\r\n");
|
|
try tmp_array_list.append("beta\r\n");
|
|
try tmp_array_list.append("\r\n");
|
|
|
|
result = try diffLinesToChars(arena.allocator(), "", "alpha\r\nbeta\r\n\r\n\r\n");
|
|
try testing.expectEqualStrings("", result.chars_1); // Empty string and blank lines #1
|
|
try testing.expectEqualStrings("\u{0001}\u{0002}\u{0003}\u{0003}", result.chars_2); // Empty string and blank lines #2
|
|
try testing.expectEqualDeep(tmp_array_list.items, result.line_array.items); // Empty string and blank lines #3
|
|
|
|
tmp_array_list.items.len = 0;
|
|
try tmp_array_list.append("");
|
|
try tmp_array_list.append("a");
|
|
try tmp_array_list.append("b");
|
|
|
|
result = try diffLinesToChars(arena.allocator(), "a", "b");
|
|
try testing.expectEqualStrings("\u{0001}", result.chars_1); // No linebreaks #1.
|
|
try testing.expectEqualStrings("\u{0002}", result.chars_2); // No linebreaks #2.
|
|
try testing.expectEqualDeep(tmp_array_list.items, result.line_array.items); // No linebreaks #3.
|
|
|
|
// TODO: More than 256 to reveal any 8-bit limitations but this requires
|
|
// some unicode logic that I don't want to deal with
|
|
|
|
// TODO: Fix this
|
|
|
|
// const n: u8 = 255;
|
|
// tmp_array_list.items.len = 0;
|
|
|
|
// var line_list = std.ArrayList(u8).init(arena.allocator());
|
|
// var char_list = std.ArrayList(u8).init(arena.allocator());
|
|
|
|
// var i: u8 = 0;
|
|
// while (i < n) : (i += 1) {
|
|
// try tmp_array_list.append(&.{ i, '\n' });
|
|
// try line_list.appendSlice(&.{ i, '\n' });
|
|
// try char_list.append(i);
|
|
// }
|
|
// try testing.expectEqual(@as(usize, n), tmp_array_list.items.len); // Test initialization fail #1
|
|
// try testing.expectEqual(@as(usize, n), char_list.items.len); // Test initialization fail #2
|
|
// try tmp_array_list.insert(0, "");
|
|
// result = try diffLinesToChars(arena.allocator(), line_list.items, "");
|
|
// try testing.expectEqualStrings(char_list.items, result.chars_1);
|
|
// try testing.expectEqualStrings("", result.chars_2);
|
|
// try testing.expectEqualDeep(tmp_array_list.items, result.line_array.items);
|
|
}
|
|
|
|
test diffCharsToLines {
|
|
var arena = std.heap.ArenaAllocator.init(testing.allocator);
|
|
defer arena.deinit();
|
|
|
|
try std.testing.expect((Diff{ .operation = .equal, .text = "a" }).eql(Diff{ .operation = .equal, .text = "a" }));
|
|
try std.testing.expect(!(Diff{ .operation = .insert, .text = "a" }).eql(Diff{ .operation = .equal, .text = "a" }));
|
|
try std.testing.expect(!(Diff{ .operation = .equal, .text = "a" }).eql(Diff{ .operation = .equal, .text = "b" }));
|
|
try std.testing.expect(!(Diff{ .operation = .equal, .text = "a" }).eql(Diff{ .operation = .delete, .text = "b" }));
|
|
|
|
// Convert chars up to lines.
|
|
var diffs = std.ArrayList(Diff).init(arena.allocator());
|
|
try diffs.appendSlice(&.{
|
|
Diff{ .operation = .equal, .text = try arena.allocator().dupe(u8, "\u{0001}\u{0002}\u{0001}") },
|
|
Diff{ .operation = .insert, .text = try arena.allocator().dupe(u8, "\u{0002}\u{0001}\u{0002}") },
|
|
});
|
|
var tmp_vector = std.ArrayList([]const u8).init(arena.allocator());
|
|
try tmp_vector.append("");
|
|
try tmp_vector.append("alpha\n");
|
|
try tmp_vector.append("beta\n");
|
|
try diffCharsToLines(arena.allocator(), diffs.items, tmp_vector.items);
|
|
|
|
try std.testing.expectEqualDeep([_]Diff{
|
|
Diff{ .operation = .equal, .text = "alpha\nbeta\nalpha\n" },
|
|
Diff{ .operation = .insert, .text = "beta\nalpha\nbeta\n" },
|
|
}, diffs.items[0..2].*);
|
|
|
|
// TODO: Implement exhaustive tests
|
|
}
|
|
|
|
fn rebuildtexts(allocator: std.mem.Allocator, diffs: std.ArrayListUnmanaged(Diff)) ![2][]const u8 {
|
|
var text = [2]std.ArrayList(u8){
|
|
std.ArrayList(u8).init(allocator),
|
|
std.ArrayList(u8).init(allocator),
|
|
};
|
|
|
|
for (diffs.items) |myDiff| {
|
|
if (myDiff.operation != .insert) {
|
|
try text[0].appendSlice(myDiff.text);
|
|
}
|
|
if (myDiff.operation != .delete) {
|
|
try text[1].appendSlice(myDiff.text);
|
|
}
|
|
}
|
|
return .{
|
|
try text[0].toOwnedSlice(),
|
|
try text[1].toOwnedSlice(),
|
|
};
|
|
}
|
|
|
|
const talloc = std.testing.allocator;
|
|
test diff {
|
|
// Perform a trivial diff.
|
|
var diffs = std.ArrayListUnmanaged(Diff){};
|
|
defer diffs.deinit(talloc);
|
|
var this = DiffMatchPatch{};
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "", "", false)); // diff: Null case.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{Diff.init(.equal, "abc")});
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "abc", "abc", false)); // diff: Equality.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.equal, "ab"), Diff.init(.insert, "123"), Diff.init(.equal, "c") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "abc", "ab123c", false)); // diff: Simple insertion.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.equal, "a"), Diff.init(.delete, "123"), Diff.init(.equal, "bc") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "a123bc", "abc", false)); // diff: Simple deletion.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.equal, "a"), Diff.init(.insert, "123"), Diff.init(.equal, "b"), Diff.init(.insert, "456"), Diff.init(.equal, "c") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "abc", "a123b456c", false)); // diff: Two insertions.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.equal, "a"), Diff.init(.delete, "123"), Diff.init(.equal, "b"), Diff.init(.delete, "456"), Diff.init(.equal, "c") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "a123b456c", "abc", false)); // diff: Two deletions.
|
|
|
|
// Perform a real diff.
|
|
// Switch off the timeout.
|
|
this.diff_timeout = 0;
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.delete, "a"), Diff.init(.insert, "b") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "a", "b", false)); // diff: Simple case #1.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.delete, "Apple"), Diff.init(.insert, "Banana"), Diff.init(.equal, "s are a"), Diff.init(.insert, "lso"), Diff.init(.equal, " fruit.") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "Apples are a fruit.", "Bananas are also fruit.", false)); // diff: Simple case #2.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.delete, "a"), Diff.init(.insert, "\u{0680}"), Diff.init(.equal, "x"), Diff.init(.delete, "\t"), Diff.init(.insert, "\x00") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "ax\t", "\u{0680}x\x00", false)); // diff: Simple case #3.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.delete, "1"), Diff.init(.equal, "a"), Diff.init(.delete, "y"), Diff.init(.equal, "b"), Diff.init(.delete, "2"), Diff.init(.insert, "xab") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "1ayb2", "abxab", false)); // diff: Overlap #1.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.insert, "xaxcx"), Diff.init(.equal, "abc"), Diff.init(.delete, "y") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "abcy", "xaxcxabc", false)); // diff: Overlap #2.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.delete, "ABCD"), Diff.init(.equal, "a"), Diff.init(.delete, "="), Diff.init(.insert, "-"), Diff.init(.equal, "bcd"), Diff.init(.delete, "="), Diff.init(.insert, "-"), Diff.init(.equal, "efghijklmnopqrs"), Diff.init(.delete, "EFGHIJKLMNOefg") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "ABCDa=bcd=efghijklmnopqrsEFGHIJKLMNOefg", "a-bcd-efghijklmnopqrs", false)); // diff: Overlap #3.
|
|
|
|
diffs.items.len = 0;
|
|
try diffs.appendSlice(talloc, &.{ Diff.init(.insert, " "), Diff.init(.equal, "a"), Diff.init(.insert, "nd"), Diff.init(.equal, " [[Pennsylvania]]"), Diff.init(.delete, " and [[New") });
|
|
try std.testing.expectEqualDeep(diffs, try this.diff(talloc, "a [[Pennsylvania]] and [[New", " and [[Pennsylvania]]", false)); // diff: Large equality.
|
|
|
|
this.diff_timeout = 100 * std.time.ms_per_s; // 100ms
|
|
// Increase the text lengths by 1024 times to ensure a timeout.
|
|
{
|
|
const a = "`Twas brillig, and the slithy toves\nDid gyre and gimble in the wabe:\nAll mimsy were the borogoves,\nAnd the mome raths outgrabe.\n" ** 10;
|
|
const b = "I am the very model of a modern major general,\nI've information vegetable, animal, and mineral,\nI know the kings of England, and I quote the fights historical,\nFrom Marathon to Waterloo, in order categorical.\n" ** 10;
|
|
const start_time = std.time.milliTimestamp();
|
|
_ = try this.diff(talloc, a, b, false); // Travis - TODO not sure what the third arg should be
|
|
const end_time = std.time.milliTimestamp();
|
|
// Test that we took at least the timeout period.
|
|
try std.testing.expect((this.diff_timeout * 1000) * 10000 <= end_time - start_time); // diff: Timeout min.
|
|
// Test that we didn't take forever (be forgiving).
|
|
// Theoretically this test could fail very occasionally if the
|
|
// OS task swaps or locks up for a second at the wrong moment.
|
|
try std.testing.expect((this.diff_timeout * 1000) * 10000 * 2 > end_time - start_time); // diff: Timeout max.
|
|
this.diff_timeout = 0;
|
|
}
|
|
{
|
|
// Test the linemode speedup.
|
|
// Must be long to pass the 100 char cutoff.
|
|
const a = "1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n";
|
|
const b = "abcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\nabcdefghij\n";
|
|
try std.testing.expectEqualDeep(try this.diff(talloc, a, b, true), try this.diff(talloc, a, b, false)); // diff: Simple line-mode.
|
|
}
|
|
{
|
|
const a = "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890";
|
|
const b = "abcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghijabcdefghij";
|
|
try std.testing.expectEqualDeep(try this.diff(talloc, a, b, true), try this.diff(talloc, a, b, false)); // diff: Single line-mode.
|
|
}
|
|
|
|
const a = "1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n1234567890\n";
|
|
const b = "abcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n1234567890\n1234567890\n1234567890\nabcdefghij\n";
|
|
const texts_linemode = try rebuildtexts(talloc, try this.diff(talloc, a, b, true));
|
|
defer {
|
|
talloc.free(texts_linemode[0]);
|
|
talloc.free(texts_linemode[1]);
|
|
}
|
|
const texts_textmode = try rebuildtexts(talloc, try this.diff(talloc, a, b, false));
|
|
defer {
|
|
talloc.free(texts_textmode[0]);
|
|
talloc.free(texts_textmode[1]);
|
|
}
|
|
try std.testing.expectEqualDeep(texts_textmode, texts_linemode); // diff: Overlap line-mode.
|
|
|
|
// Test null inputs -- not needed because nulls can't be passed in C#.
|
|
}
|