std.json.parser does not support \uxxxx escape

[donpdonp]

The streaming parser supports the "\u0040" => "@" escaping, but the non-streaming parser does not.

quick sanity check with jq util

$ jq .
"View from 15th Floor\u0040"
"View from 15th Floor@"

quick test patch

--- a/std/json.zig
+++ b/std/json.zig
@@ -1358,7 +1358,7 @@ test "json.parser.dynamic" {
-        \\      "Title":  "View from 15th Floor",
+        \\      "Title":  "View from 15th Floor\u0040",
@@ -1386,7 +1386,7 @@ test "json.parser.dynamic" {
-    testing.expect(mem.eql(u8, title.String, "View from 15th Floor"));
+    testing.expect(mem.eql(u8, title.String, "View from 15th Floor@"));

test fails

/home/donp/code/zig/github/std/json.zig:1389:19: 0x262a5c in test "json.parser.dynamic" (test)
    testing.expect(mem.eql(u8, title.String, "View from 15th Floor@"));

Also line 1352 says test "json.parser.dynamic" { when its testing the non-streaming parser.

[tiehuis]

The streaming parser is built atop the non-streaming parser. Both verify unicode escape sequences during decoding, however neither currently transforms the escape sequences to their byte representations.

I'm not 100% on if we should handle this transform for the streaming parser since the non-allocating property is nice (and it is also zero-copy). However, this is marked as a TODO in the tree parser. In particular see this function:

zig/std/json.zig

Line 1337 in 163a8e9

fn parseString(p: *Parser, allocator: *Allocator, token: Token, input: []const u8, i: usize) !Value {

We should check the string_has_escape field on the token and if present, re-parse the string and transform the escape sequences.

[marnix]

It looks like this has been implemented already? Applying the provided "quick test patch" keeps things working.

Perhaps this was implemented in #3648?