Auto merge of #34485 - tbu-:pr_unicode_debug_str, r=alexcrichton

Escape fewer Unicode codepoints in `Debug` impl of `str`

Use the same procedure as Python to determine whether a character is
printable, described in [PEP 3138]. In particular, this means that the
following character classes are escaped:

- Cc (Other, Control)
- Cf (Other, Format)
- Cs (Other, Surrogate), even though they can't appear in Rust strings
- Co (Other, Private Use)
- Cn (Other, Not Assigned)
- Zl (Separator, Line)
- Zp (Separator, Paragraph)
- Zs (Separator, Space), except for the ASCII space `' '` `0x20`

This allows for user-friendly inspection of strings that are not
English (e.g. compare `"\u{e9}\u{e8}\u{ea}"` to `"éèê"`).

Fixes #34318.
CC #34422.

[PEP 3138]: https://www.python.org/dev/peps/pep-3138/

2 files changed, 4 insertions, 4 deletions

diff --git a/src/test/run-pass/ifmt.rs b/src/test/run-pass/ifmt.rs
index ed56519d236..8b5536de12e 100644
--- a/src/test/run-pass/ifmt.rs
+++ b/src/test/run-pass/ifmt.rs
@@ -70,15 +70,15 @@ pub fn main() {
     t!(format!("{}", '☃'), "☃");
     t!(format!("{}", 10), "10");
     t!(format!("{}", 10_usize), "10");
-    t!(format!("{:?}", '☃'), "'\\u{2603}'");
+    t!(format!("{:?}", '☃'), "'☃'");
     t!(format!("{:?}", 10), "10");
     t!(format!("{:?}", 10_usize), "10");
     t!(format!("{:?}", "true"), "\"true\"");
     t!(format!("{:?}", "foo\nbar"), "\"foo\\nbar\"");
     t!(format!("{:?}", "foo\n\"bar\"\r\n\'baz\'\t\\qux\\"),
        r#""foo\n\"bar\"\r\n\'baz\'\t\\qux\\""#);
-    t!(format!("{:?}", "foo\0bar\x01baz\u{3b1}q\u{75}x"),
-       r#""foo\u{0}bar\u{1}baz\u{3b1}qux""#);
+    t!(format!("{:?}", "foo\0bar\x01baz\u{7f}q\u{75}x"),
+       r#""foo\u{0}bar\u{1}baz\u{7f}qux""#);
     t!(format!("{:o}", 10_usize), "12");
     t!(format!("{:x}", 10_usize), "a");
     t!(format!("{:X}", 10_usize), "A");
diff --git a/src/test/run-pass/sync-send-iterators-in-libcore.rs b/src/test/run-pass/sync-send-iterators-in-libcore.rs
index 93178994815..d12bdf182fa 100644
--- a/src/test/run-pass/sync-send-iterators-in-libcore.rs
+++ b/src/test/run-pass/sync-send-iterators-in-libcore.rs
@@ -67,7 +67,7 @@ macro_rules! is_sync_send {
 
 fn main() {
     // for char.rs
-    all_sync_send!("Я", escape_default, escape_unicode);
+    all_sync_send!("Я", escape_debug, escape_default, escape_unicode);
 
     // for iter.rs
     all_sync_send_mutable_ref!([1], iter);