| Ticket UUID: | 22324bcbdfdeedb511eed5a9447683ab96edfef4 | |||
| Title: | string reverse is broken in 8.6.11 | |||
| Type: | Bug | Version: | 8.6 | |
| Submitter: | chw | Created on: | 2021-02-12 17:28:13 | |
| Subsystem: | 44. UTF-8 Strings | Assigned To: | jan.nijtmans | |
| Priority: | 5 Medium | Severity: | Minor | |
| Status: | Closed | Last Modified: | 2021-02-16 12:16:45 | |
| Resolution: | Fixed | Closed By: | jan.nijtmans | |
| Closed on: | 2021-02-16 12:16:45 | |||
| Description: |
set string \ud83d\udca3 -> 💣 binary encode hex [encoding convertto utf-8 $string] -> f09f92a3 binary encode hex [encoding convertto utf-8 [string reverse $string]] -> edb2a3eda0bd | |||
| User Comments: |
jan.nijtmans added on 2021-02-16 12:16:45:
Fixed now in core-8-6-branch and up. Thanks, Christian for the POC patch. There were some corner-cases to be handled, but it was a big help in getting this right! jan.nijtmans added on 2021-02-14 17:26:23: Thanks for the patch! I prefer to fix this in 8.7 first (it's still a bug there too), and after that reconsider for backport to 8.6. chw added on 2021-02-13 05:16:49: The attached stringrev.diff is a POC patch against a core-8-6-11 checkout. chw added on 2021-02-12 17:59:23: The problem here is that versions < 8.6.11 would result in binary encode hex [encoding convertto utf-8 $string] -> eda0bdedb2a3 i.e. despite being not proper UTF-8 at least the contract of reversing the string is fulfilled, whereas 8.6.11 delivers a questionable result. Yes, I think it should be fixed, but don't know how yet. jan.nijtmans added on 2021-02-12 17:42:05: Yep, this is a known bug, since "string reverse" reverses the surrogates resulting in invalid characters. It has been this way since 8.6.0 (most likely 8.5 as well), so it isn't a regression between 8.6.10/8.6.11 (therefore changed "Version" to "8.6". I think 8.7 still has the same bug as well. It's fixed in Tcl 9.0 Some people consider changing the result of existing commands in a patch release (see also [debd088e48]) a bug, so we should be careful when fixing this in 8.6. Are you willing to supply a patch? | |||
Attachments:
- stringrev.diff [download] added by chw on 2021-02-13 05:17:43. [details]