compiler,std: implement ZON support

This commit allows using ZON (Zig Object Notation) in a few ways.

* `@import` can be used to load ZON at comptime and convert it to a
  normal Zig value. In this case, `@import` must have a result type.
* `std.zon.parse` can be used to parse ZON at runtime, akin to the
  parsing logic in `std.json`.
* `std.zon.stringify` can be used to convert arbitrary data structures
  to ZON at runtime, again akin to `std.json`.

test/cases/compile_errors/@import_zon_addr_slice.zig

@@ -0,0 +1,9 @@
+pub fn main() void {
+    const f: struct { value: []const i32 } = @import("zon/addr_slice.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/addr_slice.zon
+//
+// addr_slice.zon:2:14: error: pointers are not available in ZON

test/cases/compile_errors/@import_zon_array_len.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: [4]u8 = @import("zon/array.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/array.zon
+//
+// array.zon:1:2: error: expected type '[4]u8'
+// tmp.zig:2:30: note: imported here

test/cases/compile_errors/@import_zon_bad_import.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    _ = @import(
+        "bogus-does-not-exist.zon",
+    );
+}
+
+// error
+//
+// :3:9: error: unable to open 'bogus-does-not-exist.zon': FileNotFound

test/cases/compile_errors/@import_zon_bad_type.zig

@@ -0,0 +1,125 @@
+export fn testVoid() void {
+    const f: void = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testInStruct() void {
+    const f: struct { f: [*]const u8 } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testError() void {
+    const f: struct { error{foo} } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testInUnion() void {
+    const f: union(enum) { a: void, b: [*c]const u8 } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testInVector() void {
+    const f: @Vector(0, [*c]const u8) = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testInOpt() void {
+    const f: *const ?[*c]const u8 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testComptimeField() void {
+    const f: struct { comptime foo: ??u8 = null } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testEnumLiteral() void {
+    const f: @TypeOf(.foo) = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testNestedOpt1() void {
+    const f: ??u8 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testNestedOpt2() void {
+    const f: ?*const ?u8 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testNestedOpt3() void {
+    const f: *const ?*const ?*const u8 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testOpt() void {
+    const f: ?u8 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testNonExhaustiveEnum() void {
+    const f: enum(u8) { _ } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testUntaggedUnion() void {
+    const f: union { foo: void } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testTaggedUnionVoid() void {
+    const f: union(enum) { foo: void } = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testVisited() void {
+    const V = struct {
+        ?f32, // Adds `?f32` to the visited list
+        ??f32, // `?f32` is already visited, we need to detect the nested opt anyway
+        f32,
+    };
+    const f: V = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+export fn testMutablePointer() void {
+    const f: *i32 = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/neg_inf.zon
+//
+// tmp.zig:2:29: error: type 'void' is not available in ZON
+// tmp.zig:7:50: error: type '[*]const u8' is not available in ZON
+// tmp.zig:7:50: note: ZON does not allow many-pointers
+// tmp.zig:12:46: error: type 'error{foo}' is not available in ZON
+// tmp.zig:17:65: error: type '[*c]const u8' is not available in ZON
+// tmp.zig:17:65: note: ZON does not allow C pointers
+// tmp.zig:22:49: error: type '[*c]const u8' is not available in ZON
+// tmp.zig:22:49: note: ZON does not allow C pointers
+// tmp.zig:27:45: error: type '[*c]const u8' is not available in ZON
+// tmp.zig:27:45: note: ZON does not allow C pointers
+// tmp.zig:32:61: error: type '??u8' is not available in ZON
+// tmp.zig:32:61: note: ZON does not allow nested optionals
+// tmp.zig:42:29: error: type '??u8' is not available in ZON
+// tmp.zig:42:29: note: ZON does not allow nested optionals
+// tmp.zig:47:36: error: type '?*const ?u8' is not available in ZON
+// tmp.zig:47:36: note: ZON does not allow nested optionals
+// tmp.zig:52:50: error: type '?*const ?*const u8' is not available in ZON
+// tmp.zig:52:50: note: ZON does not allow nested optionals
+// tmp.zig:82:26: error: type '??f32' is not available in ZON
+// tmp.zig:82:26: note: ZON does not allow nested optionals
+// tmp.zig:87:29: error: type '*i32' is not available in ZON
+// tmp.zig:87:29: note: ZON does not allow mutable pointers
+// neg_inf.zon:1:1: error: expected type '@Type(.enum_literal)'
+// tmp.zig:37:38: note: imported here
+// neg_inf.zon:1:1: error: expected type '?u8'
+// tmp.zig:57:28: note: imported here
+// neg_inf.zon:1:1: error: expected type 'tmp.testNonExhaustiveEnum__enum_490'
+// tmp.zig:62:39: note: imported here
+// neg_inf.zon:1:1: error: expected type 'tmp.testUntaggedUnion__union_492'
+// tmp.zig:67:44: note: imported here
+// neg_inf.zon:1:1: error: expected type 'tmp.testTaggedUnionVoid__union_495'
+// tmp.zig:72:50: note: imported here

test/cases/compile_errors/@import_zon_comptime_inf.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: comptime_float = @import("zon/inf.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/inf.zon
+//
+// inf.zon:1:1: error: expected type 'comptime_float'
+// tmp.zig:2:39: note: imported here

test/cases/compile_errors/@import_zon_comptime_nan.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: comptime_float = @import("zon/nan.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/nan.zon
+//
+// nan.zon:1:1: error: expected type 'comptime_float'
+// tmp.zig:2:39: note: imported here

test/cases/compile_errors/@import_zon_comptime_neg_inf.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: comptime_float = @import("zon/neg_inf.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/neg_inf.zon
+//
+// neg_inf.zon:1:1: error: expected type 'comptime_float'
+// tmp.zig:2:39: note: imported here

test/cases/compile_errors/@import_zon_doc_comment.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: struct { foo: type } = @import("zon/doc_comment.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/doc_comment.zon
+//
+// doc_comment.zon:1:1: error: expected expression, found 'a document comment'

test/cases/compile_errors/@import_zon_double_negation_float.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: f32 = @import("zon/double_negation_float.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/double_negation_float.zon
+//
+// double_negation_float.zon:1:1: error: expected number or 'inf' after '-'

test/cases/compile_errors/@import_zon_double_negation_int.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: i32 = @import("zon/double_negation_int.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/double_negation_int.zon
+//
+// double_negation_int.zon:1:1: error: expected number or 'inf' after '-'

test/cases/compile_errors/@import_zon_enum_embedded_null.zig

@@ -0,0 +1,11 @@
+const std = @import("std");
+export fn entry() void {
+    const E = enum { foo };
+    const f: struct { E, E } = @import("zon/enum_embedded_null.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/enum_embedded_null.zon
+//
+// enum_embedded_null.zon:2:6: error: identifier cannot contain null bytes

test/cases/compile_errors/@import_zon_expected_void.zig

@@ -0,0 +1,11 @@
+export fn entry() void {
+    const U = union(enum) { a: void };
+    const f: U = @import("zon/simple_union.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/simple_union.zon
+//
+// simple_union.zon:1:9: error: expected type 'void'
+// tmp.zig:3:26: note: imported here

test/cases/compile_errors/@import_zon_invalid_character.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: u8 = @import("zon/invalid_character.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/invalid_character.zon
+//
+// invalid_character.zon:1:3: error: invalid escape character: 'a'

test/cases/compile_errors/@import_zon_invalid_number.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: u128 = @import("zon/invalid_number.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/invalid_number.zon
+//
+// invalid_number.zon:1:19: error: invalid digit 'a' for decimal base

test/cases/compile_errors/@import_zon_invalid_string.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: []const u8 = @import("zon/invalid_string.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/invalid_string.zon
+//
+// invalid_string.zon:1:5: error: invalid escape character: 'a'

test/cases/compile_errors/@import_zon_leading_zero_in_integer.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: u128 = @import("zon/leading_zero_in_integer.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/leading_zero_in_integer.zon
+//
+// leading_zero_in_integer.zon:1:1: error: number '0012' has leading zero
+// leading_zero_in_integer.zon:1:1: note: use '0o' prefix for octal literals

test/cases/compile_errors/@import_zon_neg_char.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: u8 = @import("zon/neg_char.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/neg_char.zon
+//
+// neg_char.zon:1:1: error: expected number or 'inf' after '-'

test/cases/compile_errors/@import_zon_neg_nan.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: u8 = @import("zon/neg_nan.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/neg_nan.zon
+//
+// neg_nan.zon:1:1: error: expected number or 'inf' after '-'

test/cases/compile_errors/@import_zon_negative_zero.zig

@@ -0,0 +1,11 @@
+export fn entry() void {
+    const f: i8 = @import("zon/negative_zero.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/negative_zero.zon
+//
+// negative_zero.zon:1:2: error: integer literal '-0' is ambiguous
+// negative_zero.zon:1:2: note: use '0' for an integer zero
+// negative_zero.zon:1:2: note: use '-0.0' for a floating-point signed zero

test/cases/compile_errors/@import_zon_no_rt.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f = @import("zon/simple_union.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/simple_union.zon
+//
+// tmp.zig:2:23: error: '@import' of ZON must have a known result type

test/cases/compile_errors/@import_zon_number_fail_limits.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: i66 = @import("zon/large_number.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/large_number.zon
+//
+// large_number.zon:1:1: error: type 'i66' cannot represent integer value '36893488147419103232'
+// tmp.zig:2:28: note: imported here

test/cases/compile_errors/@import_zon_oob_char_0.zig

@@ -0,0 +1,16 @@
+export fn entry() void {
+    {
+        const f: u6 = @import("zon/char_32.zon");
+        _ = f;
+    }
+    {
+        const f: u5 = @import("zon/char_32.zon");
+        _ = f;
+    }
+}
+
+// error
+// imports=zon/char_32.zon
+//
+// char_32.zon:1:1: error: type 'u5' cannot represent integer value '32'
+// tmp.zig:7:31: note: imported here

test/cases/compile_errors/@import_zon_oob_char_1.zig

@@ -0,0 +1,16 @@
+export fn entry() void {
+    {
+        const f: i7 = @import("zon/char_32.zon");
+        _ = f;
+    }
+    {
+        const f: i6 = @import("zon/char_32.zon");
+        _ = f;
+    }
+}
+
+// error
+// imports=zon/char_32.zon
+//
+// char_32.zon:1:1: error: type 'i6' cannot represent integer value '32'
+// tmp.zig:7:31: note: imported here

test/cases/compile_errors/@import_zon_oob_int_0.zig

@@ -0,0 +1,16 @@
+export fn entry() void {
+    {
+        const f: u6 = @import("zon/int_32.zon");
+        _ = f;
+    }
+    {
+        const f: u5 = @import("zon/int_32.zon");
+        _ = f;
+    }
+}
+
+// error
+// imports=zon/int_32.zon
+//
+// int_32.zon:1:1: error: type 'u5' cannot represent integer value '32'
+// tmp.zig:7:31: note: imported here

test/cases/compile_errors/@import_zon_oob_int_1.zig

@@ -0,0 +1,16 @@
+export fn entry() void {
+    {
+        const f: i7 = @import("zon/int_32.zon");
+        _ = f;
+    }
+    {
+        const f: i6 = @import("zon/int_32.zon");
+        _ = f;
+    }
+}
+
+// error
+// imports=zon/int_32.zon
+//
+// int_32.zon:1:1: error: type 'i6' cannot represent integer value '32'
+// tmp.zig:7:31: note: imported here

test/cases/compile_errors/@import_zon_oob_int_2.zig

@@ -0,0 +1,16 @@
+export fn entry() void {
+    {
+        const f: i7 = @import("zon/int_neg_33.zon");
+        _ = f;
+    }
+    {
+        const f: i6 = @import("zon/int_neg_33.zon");
+        _ = f;
+    }
+}
+
+// error
+// imports=zon/int_neg_33.zon
+//
+// int_neg_33.zon:1:1: error: type 'i6' cannot represent integer value '-33'
+// tmp.zig:7:31: note: imported here

test/cases/compile_errors/@import_zon_oob_int_3.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: u64 = @import("zon/int_neg_33.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/int_neg_33.zon
+//
+// int_neg_33.zon:1:1: error: type 'u64' cannot represent integer value '-33'
+// tmp.zig:2:28: note: imported here

test/cases/compile_errors/@import_zon_opt_in_err.zig

@@ -0,0 +1,82 @@
+export fn testFloatA() void {
+    const f: ?f32 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testFloatB() void {
+    const f: *const ?f32 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testFloatC() void {
+    const f: ?*const f32 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testBool() void {
+    const f: ?bool = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testInt() void {
+    const f: ?i32 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+const Enum = enum { foo };
+export fn testEnum() void {
+    const f: ?Enum = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testEnumLit() void {
+    const f: ?@TypeOf(.foo) = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testArray() void {
+    const f: ?[1]u8 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+const Union = union {};
+export fn testUnion() void {
+    const f: ?Union = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testSlice() void {
+    const f: ?[]const u8 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+export fn testVector() void {
+    const f: ?@Vector(3, f32) = @import("zon/vec2.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/vec2.zon
+//
+// vec2.zon:1:2: error: expected type '?f32'
+// tmp.zig:2:29: note: imported here
+// vec2.zon:1:2: error: expected type '*const ?f32'
+// tmp.zig:7:36: note: imported here
+// vec2.zon:1:2: error: expected type '?*const f32'
+// tmp.zig:12:36: note: imported here
+// vec2.zon:1:2: error: expected type '?bool'
+// tmp.zig:17:30: note: imported here
+// vec2.zon:1:2: error: expected type '?i32'
+// tmp.zig:22:29: note: imported here
+// vec2.zon:1:2: error: expected type '?tmp.Enum'
+// tmp.zig:28:30: note: imported here
+// vec2.zon:1:2: error: expected type '?@Type(.enum_literal)'
+// tmp.zig:33:39: note: imported here
+// vec2.zon:1:2: error: expected type '?[1]u8'
+// tmp.zig:38:31: note: imported here
+// vec2.zon:1:2: error: expected type '?tmp.Union'
+// tmp.zig:44:31: note: imported here
+// vec2.zon:1:2: error: expected type '?[]const u8'
+// tmp.zig:49:36: note: imported here
+// vec2.zon:1:2: error: expected type '?@Vector(3, f32)'
+// tmp.zig:54:41: note: imported here

test/cases/compile_errors/@import_zon_opt_in_err_struct.zig

@@ -0,0 +1,19 @@
+const Struct = struct { f: bool };
+export fn testStruct() void {
+    const f: ?Struct = @import("zon/nan.zon");
+    _ = f;
+}
+
+const Tuple = struct { bool };
+export fn testTuple() void {
+    const f: ?Tuple = @import("zon/nan.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/nan.zon
+//
+//nan.zon:1:1: error: expected type '?tmp.Struct'
+//tmp.zig:3:32: note: imported here
+//nan.zon:1:1: error: expected type '?struct { bool }'
+//tmp.zig:9:31: note: imported here

test/cases/compile_errors/@import_zon_string_as_array.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: [5]u8 = @import("zon/hello.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/hello.zon
+//
+// hello.zon:1:1: error: expected type '[5]u8'
+// tmp.zig:2:30: note: imported here

test/cases/compile_errors/@import_zon_struct_dup_field.zig

@@ -0,0 +1,11 @@
+const std = @import("std");
+export fn entry() void {
+    const f: struct { name: u8 } = @import("zon/struct_dup_field.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/struct_dup_field.zon
+//
+// struct_dup_field.zon:2:6: error: duplicate struct field name
+// struct_dup_field.zon:3:6: note: duplicate name here

test/cases/compile_errors/@import_zon_struct_wrong_comptime_field.zig

@@ -0,0 +1,14 @@
+export fn entry() void {
+    const Vec2 = struct {
+        comptime x: f32 = 1.5,
+        comptime y: f32 = 2.5,
+    };
+    const f: Vec2 = @import("zon/vec2.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/vec2.zon
+//
+// vec2.zon:1:19: error: value stored in comptime field does not match the default value of the field
+// tmp.zig:6:29: note: imported here

test/cases/compile_errors/@import_zon_syntax_error.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: bool = @import("zon/syntax_error.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/syntax_error.zon
+//
+// syntax_error.zon:3:13: error: expected ',' after initializer

test/cases/compile_errors/@import_zon_tuple_wrong_comptime_field.zig

@@ -0,0 +1,14 @@
+export fn entry() void {
+    const T = struct {
+        comptime f32 = 1.5,
+        comptime f32 = 2.5,
+    };
+    const f: T = @import("zon/tuple.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/tuple.zon
+//
+// tuple.zon:1:9: error: value stored in comptime field does not match the default value of the field
+// tmp.zig:6:26: note: imported here

test/cases/compile_errors/@import_zon_type_decl.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: struct { foo: type } = @import("zon/type_decl.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/type_decl.zon
+//
+// type_decl.zon:2:12: error: types are not available in ZON

test/cases/compile_errors/@import_zon_type_expr_array.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: [3]i32 = @import("zon/type_expr_array.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/type_expr_array.zon
+//
+// type_expr_array.zon:1:1: error: types are not available in ZON
+// type_expr_array.zon:1:1: note: replace the type with '.'

test/cases/compile_errors/@import_zon_type_expr_fn.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: i32 = @import("zon/type_expr_fn.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/type_expr_fn.zon
+//
+// type_expr_fn.zon:1:1: error: types are not available in ZON
+// type_expr_fn.zon:1:1: note: replace the type with '.'

test/cases/compile_errors/@import_zon_type_expr_struct.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: struct { x: f32, y: f32 } = @import("zon/type_expr_struct.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/type_expr_struct.zon
+//
+// type_expr_struct.zon:1:1: error: types are not available in ZON
+// type_expr_struct.zon:1:1: note: replace the type with '.'

test/cases/compile_errors/@import_zon_type_expr_tuple.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: struct { f32, f32 } = @import("zon/type_expr_tuple.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/type_expr_tuple.zon
+//
+// type_expr_tuple.zon:1:1: error: types are not available in ZON
+// type_expr_tuple.zon:1:1: note: replace the type with '.'

test/cases/compile_errors/@import_zon_type_mismatch.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: bool = @import("zon/struct.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/struct.zon
+//
+// struct.zon:1:2: error: expected type 'bool'
+// tmp.zig:2:29: note: imported here

test/cases/compile_errors/@import_zon_unescaped_newline.zig

@@ -0,0 +1,9 @@
+export fn entry() void {
+    const f: i8 = @import("zon/unescaped_newline.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/unescaped_newline.zon
+//
+// unescaped_newline.zon:1:1: error: expected expression, found 'invalid token'

test/cases/compile_errors/@import_zon_unknown_ident.zig

@@ -0,0 +1,11 @@
+export fn entry() void {
+    const f: struct { value: bool } = @import("zon/unknown_ident.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/unknown_ident.zon
+//
+// unknown_ident.zon:2:14: error: invalid expression
+// unknown_ident.zon:2:14: note: ZON allows identifiers 'true', 'false', 'null', 'inf', and 'nan'
+// unknown_ident.zon:2:14: note: precede identifier with '.' for an enum literal

test/cases/compile_errors/@import_zon_vec_too_few.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: @Vector(3, f32) = @import("zon/tuple.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/tuple.zon
+//
+// tuple.zon:1:2: error: expected 3 vector elements; found 2
+// tmp.zig:2:40: note: imported here

test/cases/compile_errors/@import_zon_vec_too_many.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: @Vector(1, f32) = @import("zon/tuple.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/tuple.zon
+//
+// tuple.zon:1:2: error: expected 1 vector elements; found 2
+// tmp.zig:2:40: note: imported here

test/cases/compile_errors/@import_zon_vec_wrong_type.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: @Vector(2, bool) = @import("zon/tuple.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/tuple.zon
+//
+// tuple.zon:1:4: error: expected type 'bool'
+// tmp.zig:2:41: note: imported here

test/cases/compile_errors/@import_zon_void.zig

@@ -0,0 +1,10 @@
+export fn entry() void {
+    const f: union { foo: void } = @import("zon/void.zon");
+    _ = f;
+}
+
+// error
+// imports=zon/void.zon
+//
+// void.zon:1:11: error: void literals are not available in ZON
+// void.zon:1:11: note: void union payloads can be represented by enum literals

test/cases/compile_errors/redundant_try.zig

@@ -44,9 +44,9 @@ comptime {
 //
 // :5:23: error: expected error union type, found 'comptime_int'
 // :10:23: error: expected error union type, found '@TypeOf(.{})'
-// :15:23: error: expected error union type, found 'tmp.test2__struct_493'
+// :15:23: error: expected error union type, found 'tmp.test2__struct_494'
 // :15:23: note: struct declared here
-// :20:27: error: expected error union type, found 'tmp.test3__struct_495'
+// :20:27: error: expected error union type, found 'tmp.test3__struct_496'
 // :20:27: note: struct declared here
 // :25:23: error: expected error union type, found 'struct { comptime *const [5:0]u8 = "hello" }'
 // :31:13: error: expected error union type, found 'u32'

test/cases/compile_errors/zon/addr_slice.zon

@@ -0,0 +1,3 @@
+.{
+    .value = &.{ 1, 2, 3 },
+}

test/cases/compile_errors/zon/array.zon

@@ -0,0 +1 @@
+.{ 'a', 'b', 'c' }

test/cases/compile_errors/zon/char_32.zon

@@ -0,0 +1 @@
+' '

test/cases/compile_errors/zon/desktop.ini

@@ -0,0 +1,3 @@
+[LocalizedFileNames]
+invalid_zon_2.zig=@invalid_zon_2.zig,0
+invalid_zon_1.zig=@invalid_zon_1.zig,0

test/cases/compile_errors/zon/doc_comment.zon

@@ -0,0 +1,2 @@
+//! Doc comments aren't allowed in ZON
+.{}

test/cases/compile_errors/zon/double_negation_float.zon

@@ -0,0 +1 @@
+--1.0

test/cases/compile_errors/zon/double_negation_int.zon

@@ -0,0 +1 @@
+--1

test/cases/compile_errors/zon/enum_embedded_null.zon

@@ -0,0 +1,4 @@
+.{
+    .@"\x00",
+    10,
+}

test/cases/compile_errors/zon/hello.zon

@@ -0,0 +1 @@
+"hello"

test/cases/compile_errors/zon/inf.zon

@@ -0,0 +1 @@
+inf

test/cases/compile_errors/zon/int_32.zon

@@ -0,0 +1 @@
+32

test/cases/compile_errors/zon/int_neg_33.zon

@@ -0,0 +1 @@
+-33

test/cases/compile_errors/zon/invalid_character.zon

@@ -0,0 +1 @@
+'\a'

test/cases/compile_errors/zon/invalid_number.zon

@@ -0,0 +1 @@
+368934881474191032a32

test/cases/compile_errors/zon/invalid_string.zon

@@ -0,0 +1 @@
+"\"\a\""

test/cases/compile_errors/zon/large_number.zon

@@ -0,0 +1 @@
+36893488147419103232

test/cases/compile_errors/zon/leading_zero_in_integer.zon

@@ -0,0 +1 @@
+0012

test/cases/compile_errors/zon/nan.zon

@@ -0,0 +1 @@
+nan

test/cases/compile_errors/zon/neg_char.zon

@@ -0,0 +1 @@
+-'a'

test/cases/compile_errors/zon/neg_inf.zon

@@ -0,0 +1 @@
+-inf

test/cases/compile_errors/zon/neg_nan.zon

@@ -0,0 +1 @@
+-nan

test/cases/compile_errors/zon/negative_zero.zon

@@ -0,0 +1 @@
+-0

test/cases/compile_errors/zon/simple_union.zon

@@ -0,0 +1 @@
+.{ .a = 10 }

test/cases/compile_errors/zon/struct.zon

@@ -0,0 +1,4 @@
+.{
+    .boolean = true,
+    .number = 123,
+}

test/cases/compile_errors/zon/struct_dup_field.zon

@@ -0,0 +1,4 @@
+.{
+    .name = 10,
+    .name = 20,
+}

test/cases/compile_errors/zon/syntax_error.zon

@@ -0,0 +1,4 @@
+.{
+    .boolean = true
+    .number = 123,
+}

test/cases/compile_errors/zon/tuple.zon

@@ -0,0 +1 @@
+.{ 1.5, 2 }

test/cases/compile_errors/zon/type_decl.zon

@@ -0,0 +1,3 @@
+.{
+    .foo = struct {},
+}

test/cases/compile_errors/zon/type_expr_array.zon

@@ -0,0 +1 @@
+[3]i32{1, 2, 3}

test/cases/compile_errors/zon/type_expr_fn.zon

@@ -0,0 +1 @@
+fn foo() void {}

test/cases/compile_errors/zon/type_expr_struct.zon

@@ -0,0 +1 @@
+Vec2{ .x = 1.0, .y = 2.0 }

test/cases/compile_errors/zon/type_expr_tuple.zon

@@ -0,0 +1 @@
+Vec2{1.0,  2.0}

test/cases/compile_errors/zon/unescaped_newline.zon

@@ -0,0 +1,2 @@
+"a
+b"

test/cases/compile_errors/zon/unknown_ident.zon

@@ -0,0 +1,3 @@
+.{
+    .value = truefalse,
+}

test/cases/compile_errors/zon/vec2.zon

@@ -0,0 +1 @@
+.{ .x = 1.5, .y = 2 }

test/cases/compile_errors/zon/void.zon

@@ -0,0 +1 @@
+.{ .foo = {} }