zig/test/cases/while.zig
Andrew Kelley ec1b6f6673
breaking syntax change: ??x to x.? (#1095)
See #1023

This also renames Nullable/Maybe to Optional
2018-06-09 23:42:14 -04:00

228 lines
4.6 KiB
Zig

const assert = @import("std").debug.assert;
test "while loop" {
var i: i32 = 0;
while (i < 4) {
i += 1;
}
assert(i == 4);
assert(whileLoop1() == 1);
}
fn whileLoop1() i32 {
return whileLoop2();
}
fn whileLoop2() i32 {
while (true) {
return 1;
}
}
test "static eval while" {
assert(static_eval_while_number == 1);
}
const static_eval_while_number = staticWhileLoop1();
fn staticWhileLoop1() i32 {
return whileLoop2();
}
fn staticWhileLoop2() i32 {
while (true) {
return 1;
}
}
test "continue and break" {
runContinueAndBreakTest();
assert(continue_and_break_counter == 8);
}
var continue_and_break_counter: i32 = 0;
fn runContinueAndBreakTest() void {
var i: i32 = 0;
while (true) {
continue_and_break_counter += 2;
i += 1;
if (i < 4) {
continue;
}
break;
}
assert(i == 4);
}
test "return with implicit cast from while loop" {
returnWithImplicitCastFromWhileLoopTest() catch unreachable;
}
fn returnWithImplicitCastFromWhileLoopTest() error!void {
while (true) {
return;
}
}
test "while with continue expression" {
var sum: i32 = 0;
{
var i: i32 = 0;
while (i < 10) : (i += 1) {
if (i == 5) continue;
sum += i;
}
}
assert(sum == 40);
}
test "while with else" {
var sum: i32 = 0;
var i: i32 = 0;
var got_else: i32 = 0;
while (i < 10) : (i += 1) {
sum += 1;
} else {
got_else += 1;
}
assert(sum == 10);
assert(got_else == 1);
}
test "while with optional as condition" {
numbers_left = 10;
var sum: i32 = 0;
while (getNumberOrNull()) |value| {
sum += value;
}
assert(sum == 45);
}
test "while with optional as condition with else" {
numbers_left = 10;
var sum: i32 = 0;
var got_else: i32 = 0;
while (getNumberOrNull()) |value| {
sum += value;
assert(got_else == 0);
} else {
got_else += 1;
}
assert(sum == 45);
assert(got_else == 1);
}
test "while with error union condition" {
numbers_left = 10;
var sum: i32 = 0;
var got_else: i32 = 0;
while (getNumberOrErr()) |value| {
sum += value;
} else |err| {
assert(err == error.OutOfNumbers);
got_else += 1;
}
assert(sum == 45);
assert(got_else == 1);
}
var numbers_left: i32 = undefined;
fn getNumberOrErr() error!i32 {
return if (numbers_left == 0) error.OutOfNumbers else x: {
numbers_left -= 1;
break :x numbers_left;
};
}
fn getNumberOrNull() ?i32 {
return if (numbers_left == 0) null else x: {
numbers_left -= 1;
break :x numbers_left;
};
}
test "while on optional with else result follow else prong" {
const result = while (returnNull()) |value| {
break value;
} else
i32(2);
assert(result == 2);
}
test "while on optional with else result follow break prong" {
const result = while (returnOptional(10)) |value| {
break value;
} else
i32(2);
assert(result == 10);
}
test "while on error union with else result follow else prong" {
const result = while (returnError()) |value| {
break value;
} else |err|
i32(2);
assert(result == 2);
}
test "while on error union with else result follow break prong" {
const result = while (returnSuccess(10)) |value| {
break value;
} else |err|
i32(2);
assert(result == 10);
}
test "while on bool with else result follow else prong" {
const result = while (returnFalse()) {
break i32(10);
} else
i32(2);
assert(result == 2);
}
test "while on bool with else result follow break prong" {
const result = while (returnTrue()) {
break i32(10);
} else
i32(2);
assert(result == 10);
}
test "break from outer while loop" {
testBreakOuter();
comptime testBreakOuter();
}
fn testBreakOuter() void {
outer: while (true) {
while (true) {
break :outer;
}
}
}
test "continue outer while loop" {
testContinueOuter();
comptime testContinueOuter();
}
fn testContinueOuter() void {
var i: usize = 0;
outer: while (i < 10) : (i += 1) {
while (true) {
continue :outer;
}
}
}
fn returnNull() ?i32 {
return null;
}
fn returnOptional(x: i32) ?i32 {
return x;
}
fn returnError() error!i32 {
return error.YouWantedAnError;
}
fn returnSuccess(x: i32) error!i32 {
return x;
}
fn returnFalse() bool {
return false;
}
fn returnTrue() bool {
return true;
}