Commit 5b6326ec6540d1b7af8de1176f657672be72a1e4 | zig

author	Techatrix <techatrix@mailbox.org> 2024-12-29 06:47:15+01:00
committer	Techatrix <techatrix@mailbox.org> 2024-12-29 07:00:39+01:00
log	5b6326ec6540d1b7af8de1176f657672be72a1e4
tree	60d3a3c3ad1f5c68d12c33ae7b4181af9331fc1c
parent	5d51d4474a0c61f08c264c03ecbdf651d91afe82
signature	Signed by SSH key SHA256:HYC3SjXQcAt6uwv9pu/6OoVQ2rUH8rb5zKiUHSe9uxk

fix slice of slice with sentinel on the lhs slice

example:
```zig
test {
    var foo: [2:0]u8 = .{ 1, 2 };
    _ = foo[0.. :1][0..2];
}
```

A `.slice_open` ast node will not have a end index nor sentinel.

4 files changed, 57 insertions(+), 11 deletions(-)

lib
- std
  - zig
    AstGen.zig
test
- behavior
  - slice.zig
- cases
  - safety
    slice by length sentinel mismatch on lhs.zig
    slice by length sentinel mismatch on rhs.zig

lib/std/zig/AstGen.zig+4-11

...	...	@@ -881,21 +881,14 @@ fn expr(gz: GenZir, scope: Scope, ri: ResultInfo, node: Ast.Node.Index) InnerE
881	881	.slice_sentinel,
882	882	=> {
883	883	const full = tree.fullSlice(node).?;
884		const lhs_tag = node_tags[full.ast.sliced];
885		const lhs_is_slice_sentinel = lhs_tag == .slice_sentinel;
886		const lhs_is_open_slice = lhs_tag == .slice_open or
887		(lhs_is_slice_sentinel and tree.fullSlice(full.ast.sliced).?.ast.end == 0);
888	884	if (full.ast.end != 0 and
889		lhs_is_open_slice and
	885	node_tags[full.ast.sliced] == .slice_open and
890	886	nodeIsTriviallyZero(tree, full.ast.start))
891	887	{
892		const lhs = try expr(gz, scope, .{ .rl = .ref }, node_datas[full.ast.sliced].lhs);
893
894		const start = if (lhs_is_slice_sentinel) start: {
895		const lhs_extra = tree.extraData(node_datas[full.ast.sliced].rhs, Ast.Node.SliceSentinel);
896		break :start try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, lhs_extra.start);
897		} else try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, node_datas[full.ast.sliced].rhs);
	888	const lhs_extra = tree.sliceOpen(full.ast.sliced).ast;
898	889
	890	const lhs = try expr(gz, scope, .{ .rl = .ref }, lhs_extra.sliced);
	891	const start = try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, lhs_extra.start);
899	892	const cursor = maybeAdvanceSourceCursorToMainToken(gz, node);
900	893	const len = try expr(gz, scope, .{ .rl = .{ .coerced_ty = .usize_type } }, full.ast.end);
901	894	const sentinel = if (full.ast.sentinel != 0) try expr(gz, scope, .{ .rl = .none }, full.ast.sentinel) else .none;

test/behavior/slice.zig+17

...	...	@@ -115,6 +115,23 @@ test "open slice of open slice with sentinel" {
115	115	try expect(slice[1..][0.. :0][4] == 0);
116	116	}
117	117
	118	test "open slice with sentinel of slice with end index" {
	119	if (builtin.zig_backend == .stage2_sparc64) return error.SkipZigTest; // TODO
	120
	121	var slice: [:0]const u8 = "hello";
	122	_ = &slice;
	123
	124	comptime assert(@TypeOf(slice[0.. :0][0..5]) == *const [5]u8);
	125	try expect(slice[0.. :0][0..5].len == 5);
	126	try expect(slice[0.. :0][0..5][0] == 'h');
	127	try expect(slice[0.. :0][0..5][4] == 'o');
	128
	129	comptime assert(@TypeOf(slice[0.. :0][0..5 :0]) == *const [5:0]u8);
	130	try expect(slice[0.. :0][0..5 :0].len == 5);
	131	try expect(slice[0.. :0][0..5 :0][0] == 'h');
	132	try expect(slice[0.. :0][0..5 :0][5] == 0);
	133	}
	134
118	135	test "slice of type" {
119	136	comptime {
120	137	var types_array = [_]type{ i32, f64, type };

test/cases/safety/slice by length sentinel mismatch on lhs.zig created+18

...	...	@@ -0,0 +1,18 @@
	1	const std = @import("std");
	2
	3	pub fn panic(message: []const u8, stack_trace: ?*std.builtin.StackTrace, _: ?usize) noreturn {
	4	_ = stack_trace;
	5	if (std.mem.eql(u8, message, "sentinel mismatch: expected 1, found 3")) {
	6	std.process.exit(0);
	7	}
	8	std.process.exit(1);
	9	}
	10	pub fn main() !void {
	11	var buf: [4:0]u8 = .{ 1, 2, 3, 4 };
	12	const slice = buf[0..][0..2 :1];
	13	_ = slice;
	14	return error.TestFailed;
	15	}
	16	// run
	17	// backend=llvm
	18	// target=native

test/cases/safety/slice by length sentinel mismatch on rhs.zig created+18

...	...	@@ -0,0 +1,18 @@
	1	const std = @import("std");
	2
	3	pub fn panic(message: []const u8, stack_trace: ?*std.builtin.StackTrace, _: ?usize) noreturn {
	4	_ = stack_trace;
	5	if (std.mem.eql(u8, message, "sentinel mismatch: expected 1, found 0")) {
	6	std.process.exit(0);
	7	}
	8	std.process.exit(1);
	9	}
	10	pub fn main() !void {
	11	var buf: [4:0]u8 = .{ 1, 2, 3, 4 };
	12	const slice = buf[0.. :1][0..2];
	13	_ = slice;
	14	return error.TestFailed;
	15	}
	16	// run
	17	// backend=llvm
	18	// target=native