bug#81650: [PATCH] Flymake diagnostics are not cleared in yaml-ts-mode when all errors are fixed

> Date: Tue, 18 Aug 2026 09:16:08 -0400
> From: James Cherti <[email protected]>
> 
> When editing a file in yaml-ts-mode (emacs 31 and 32) with
> Flymake enabled, resolving all linting errors does not clear
> the diagnostic highlights. The previous error overlays
> remain visible in the buffer despite the file being
> completely valid and passing all yamllint checks.
> 
> Steps to Reproduce:
> 
> 1. Open a YAML file in Emacs using yaml-ts-mode.
> 2. Ensure Flymake is active and yamllint is available in
>     your exec-path.
> 3. Introduce a syntax or formatting error into the file.
> 4. Wait for Flymake to run and highlight the error.
> 5. Fix the error.
> 6. Wait for Flymake to run again.
> 
> The attached patch fixes the issue by moving the (funcall
> report-fn diags) call outside of the while loop, ensuring
> that Flymake receives the updated empty list and
> successfully clears the obsolete diagnostics.

Thanks.

Spencer, any comments?

> From ad437d1823cf2a3e88c802f725d59aab69c47bb4 Mon Sep 17 00:00:00 2001
> From: James Cherti <[email protected]>
> Date: Tue, 18 Aug 2026 08:43:26 -0400
> Subject: [PATCH] Fix diagnostics clearing in yaml-ts-mode-flymake
> 
> * lisp/textmodes/yaml-ts-mode.el (yaml-ts-mode-flymake): Call
> the 'report-fn' callback outside the 'while' loop.  This change
> ensures that Flymake receives an empty list of diagnostics and
> clears old highlights when the YAML file has no linting errors.
> ---
>  lisp/textmodes/yaml-ts-mode.el | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lisp/textmodes/yaml-ts-mode.el b/lisp/textmodes/yaml-ts-mode.el
> index 95fd4b6a78a..a356027c271 100644
> --- a/lisp/textmodes/yaml-ts-mode.el
> +++ b/lisp/textmodes/yaml-ts-mode.el
> @@ -247,12 +247,12 @@ yaml-ts-mode-flymake
>                                          (type (if (string= "[warning]" (match-string 3))
>                                                    :warning
>                                                  :error)))
>                                     (push (flymake-make-diagnostic
>                                            source beg end type msg)
> -                                         diags))
> -                                 (funcall report-fn diags))))
> +                                         diags)))
> +                               (funcall report-fn diags)))
>                           (flymake-log :warning "Canceling obsolete check %s" proc))
>                       (kill-buffer (process-buffer proc)))))))
>          (process-send-region yaml-ts-mode--flymake-process (point-min) (point-max))
>          (process-send-eof yaml-ts-mode--flymake-process)))))
>  
> -- 
> 2.54.0
>