[clang] [emacs][clang-format] Add elisp API for clang-format on git diffs (PR #112792)

[Campbell Barton via cfe-commits]

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@@ -146,18 +146,125 @@ is a zero-based file offset, assuming ‘utf-8-unix’ coding."
     (lambda (byte &optional _quality _coding-system)
       (byte-to-position (1+ byte)))))
 
-;;;###autoload
-(defun clang-format-region (start end &optional style assume-file-name)
-  "Use clang-format to format the code between START and END according to STYLE.
-If called interactively uses the region or the current statement if there is no
-no active region. If no STYLE is given uses `clang-format-style'. Use
-ASSUME-FILE-NAME to locate a style config file, if no ASSUME-FILE-NAME is given
-uses the function `buffer-file-name'."
-  (interactive
-   (if (use-region-p)
-       (list (region-beginning) (region-end))
-     (list (point) (point))))
+(defmacro clang-format--with-delete-files-guard (bind-files-to-delete &rest body)
+  "Execute BODY which may add temp files to BIND-FILES-TO-DELETE."
+  (declare (indent 1))
+  `(let ((,bind-files-to-delete nil))
+     (unwind-protect
+         (progn
+           , at body)
+       (while ,bind-files-to-delete
+         (with-demoted-errors "failed to remove file: %S"
+           (delete-file (pop ,bind-files-to-delete)))))))
+
+
+(defun clang-format--vc-diff-get-diff-lines (file-orig file-new)
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ideasman42 wrote:

\*picky\* - personal preference, but I find it odd that the function returns command line arguments for clang-format.

It can return a list of cons-pairs of instead `(list (cons int int) ...)`  instead, then the clang-format function can convert them to the arguments used by clang-format.

(the patch I attached did this).

https://github.com/llvm/llvm-project/pull/112792