zig/test/cases/switch.zig
Andrew Kelley 451ce09067 new unreachable syntax
* `noreturn` is the primitive type.
 * `unreachable` is a control flow keyword.
 * `@unreachable()` builtin function is deleted.

closes #214
2017-03-26 04:58:48 -04:00

141 lines
2.8 KiB
Zig

const assert = @import("std").debug.assert;
test "switchWithNumbers" {
testSwitchWithNumbers(13);
}
fn testSwitchWithNumbers(x: u32) {
const result = switch (x) {
1, 2, 3, 4 ... 8 => false,
13 => true,
else => false,
};
assert(result);
}
test "switchWithAllRanges" {
assert(testSwitchWithAllRanges(50, 3) == 1);
assert(testSwitchWithAllRanges(101, 0) == 2);
assert(testSwitchWithAllRanges(300, 5) == 3);
assert(testSwitchWithAllRanges(301, 6) == 6);
}
fn testSwitchWithAllRanges(x: u32, y: u32) -> u32 {
switch (x) {
0 ... 100 => 1,
101 ... 200 => 2,
201 ... 300 => 3,
else => y,
}
}
test "implicitComptimeSwitch" {
const x = 3 + 4;
const result = switch (x) {
3 => 10,
4 => 11,
5, 6 => 12,
7, 8 => 13,
else => 14,
};
comptime {
assert(result + 1 == 14);
}
}
test "switchOnEnum" {
const fruit = Fruit.Orange;
nonConstSwitchOnEnum(fruit);
}
const Fruit = enum {
Apple,
Orange,
Banana,
};
fn nonConstSwitchOnEnum(fruit: Fruit) {
switch (fruit) {
Fruit.Apple => unreachable,
Fruit.Orange => {},
Fruit.Banana => unreachable,
}
}
test "switchStatement" {
nonConstSwitch(SwitchStatmentFoo.C);
}
fn nonConstSwitch(foo: SwitchStatmentFoo) {
const val = switch (foo) {
SwitchStatmentFoo.A => i32(1),
SwitchStatmentFoo.B => 2,
SwitchStatmentFoo.C => 3,
SwitchStatmentFoo.D => 4,
};
if (val != 3) unreachable;
}
const SwitchStatmentFoo = enum {
A,
B,
C,
D,
};
test "switchProngWithVar" {
switchProngWithVarFn(SwitchProngWithVarEnum.One {13});
switchProngWithVarFn(SwitchProngWithVarEnum.Two {13.0});
switchProngWithVarFn(SwitchProngWithVarEnum.Meh);
}
const SwitchProngWithVarEnum = enum {
One: i32,
Two: f32,
Meh,
};
fn switchProngWithVarFn(a: &const SwitchProngWithVarEnum) {
switch(*a) {
SwitchProngWithVarEnum.One => |x| {
if (x != 13) unreachable;
},
SwitchProngWithVarEnum.Two => |x| {
if (x != 13.0) unreachable;
},
SwitchProngWithVarEnum.Meh => |x| {
const v: void = x;
},
}
}
test "switchWithMultipleExpressions" {
const x = switch (returnsFive()) {
1, 2, 3 => 1,
4, 5, 6 => 2,
else => i32(3),
};
assert(x == 2);
}
fn returnsFive() -> i32 {
5
}
const Number = enum {
One: u64,
Two: u8,
Three: f32,
};
const number = Number.Three { 1.23 };
fn returnsFalse() -> bool {
switch (number) {
Number.One => |x| return x > 1234,
Number.Two => |x| return x == 'a',
Number.Three => |x| return x > 12.34,
}
}
test "switchOnConstEnumWithVar" {
assert(!returnsFalse());
}