jimzah/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2024-11-26 15:12:31 +00:00
Code Issues Actions 1 Packages Projects Releases Wiki Activity

std.mem: adjust semantics

Browse Source 
* some kinds of types require comptime calls to eql
* don't rely on compare equal for undefined
This commit is contained in:
Andrew Kelley 2024-11-22 15:30:07 -08:00
parent a3342cea18
commit 4e380b89b8
1 changed files with 25 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
lib/std/mem.zig
View File

@ -654,21 +654,14 @@ const eqlBytes_allowed = switch (builtin.zig_backend) {
else => !builtin.fuzz,
};
/// Compares two slices and returns whether they are equal.
/// Returns true if and only if the slices have the same length and all elements
/// compare true using equality operator.
pub fn eql(comptime T: type, a: []const T, b: []const T) bool {
switch (@typeInfo(T)) {
.Type, .ComptimeInt, .ComptimeFloat => {
if (a.len != b.len) return false;
inline for (a, b) |a_elem, b_elem| {
if (a_elem != b_elem) return false;
}
return true;
},
.Null, .Undefined => return a.len == b.len,
else => {},
if (!@inComptime() and @sizeOf(T) != 0 and std.meta.hasUniqueRepresentation(T) and
eqlBytes_allowed)
{
return eqlBytes(sliceAsBytes(a), sliceAsBytes(b));
}
if (@sizeOf(T) == 0) return a.len == b.len;
if (!@inComptime() and std.meta.hasUniqueRepresentation(T) and eqlBytes_allowed) return eqlBytes(sliceAsBytes(a), sliceAsBytes(b));
if (a.len != b.len) return false;
if (a.len == 0 or a.ptr == b.ptr) return true;
@ -679,6 +672,25 @@ pub fn eql(comptime T: type, a: []const T, b: []const T) bool {
return true;
}
test eql {
try testing.expect(eql(u8, "abcd", "abcd"));
try testing.expect(!eql(u8, "abcdef", "abZdef"));
try testing.expect(!eql(u8, "abcdefg", "abcdef"));
comptime {
try testing.expect(eql(type, &.{ bool, f32 }, &.{ bool, f32 }));
try testing.expect(!eql(type, &.{ bool, f32 }, &.{ f32, bool }));
try testing.expect(!eql(type, &.{ bool, f32 }, &.{bool}));
try testing.expect(eql(comptime_int, &.{ 1, 2, 3 }, &.{ 1, 2, 3 }));
try testing.expect(!eql(comptime_int, &.{ 1, 2, 3 }, &.{ 3, 2, 1 }));
try testing.expect(!eql(comptime_int, &.{1}, &.{ 1, 2 }));
}
try testing.expect(eql(void, &.{ {}, {} }, &.{ {}, {} }));
try testing.expect(!eql(void, &.{{}}, &.{ {}, {} }));
}
/// std.mem.eql heavily optimized for slices of bytes.
fn eqlBytes(a: []const u8, b: []const u8) bool {
comptime assert(eqlBytes_allowed);
@ -3303,32 +3315,6 @@ test concat {
}
}
test eql {
try testing.expect(eql(u8, "abcd", "abcd"));
try testing.expect(!eql(u8, "abcdef", "abZdef"));
try testing.expect(!eql(u8, "abcdefg", "abcdef"));
try testing.expect(eql(type, &.{ bool, f32 }, &.{ bool, f32 }));
try testing.expect(!eql(type, &.{ bool, f32 }, &.{ f32, bool }));
try testing.expect(!eql(type, &.{ bool, f32 }, &.{bool}));
try testing.expect(eql(comptime_int, &.{ 1, 2, 3 }, &.{ 1, 2, 3 }));
try testing.expect(!eql(comptime_int, &.{ 1, 2, 3 }, &.{ 3, 2, 1 }));
try testing.expect(!eql(comptime_int, &.{1}, &.{ 1, 2 }));
try testing.expect(eql(@TypeOf(undefined), &.{ undefined, undefined }, &.{ undefined, undefined }));
try testing.expect(!eql(@TypeOf(undefined), &.{undefined}, &.{ undefined, undefined }));
try testing.expect(eql(enum {}, &.{ undefined, undefined }, &.{ undefined, undefined }));
try testing.expect(!eql(enum {}, &.{undefined}, &.{ undefined, undefined }));
try testing.expect(eql(void, &.{ {}, {} }, &.{ {}, {} }));
try testing.expect(!eql(void, &.{{}}, &.{ {}, {} }));
try testing.expect(eql(@TypeOf(null), &.{ null, null }, &.{ null, null }));
try testing.expect(!eql(@TypeOf(null), &.{null}, &.{ null, null }));
}
fn moreReadIntTests() !void {
{
const bytes = [_]u8{