[Windows] Add git-clang-format wrapper bat file

[llvm-beanz]

This allows git-clang-format to be used on a Windows terminal without manually needing to find the path and invoke the python interpreter. We have a similar script for scan-build.

Fixes #69643

[llvmbot]

@llvm/pr-subscribers-clang-format

Author: Chris B (llvm-beanz)

Changes

This allows git-clang-format to be used on a Windows terminal without manually needing to find the path and invoke the python interpreter. We have a similar script for scan-build.

---

Full diff: https://github.com/llvm/llvm-project/pull/69228.diff

2 Files Affected:

• (modified) clang/tools/clang-format/CMakeLists.txt (+6)
• (added) clang/tools/clang-format/git-clang-format.bat (+1)

diff --git a/clang/tools/clang-format/CMakeLists.txt b/clang/tools/clang-format/CMakeLists.txt
index 30c93f8667c8359..1c61a3c8fb80368 100644
--- a/clang/tools/clang-format/CMakeLists.txt
+++ b/clang/tools/clang-format/CMakeLists.txt
@@ -38,3 +38,9 @@ install(FILES clang-format.py
 install(PROGRAMS git-clang-format
   DESTINATION "${CMAKE_INSTALL_BINDIR}"
   COMPONENT clang-format)
+
+if (WIN32 AND NOT CYGWIN)
+  install(PROGRAMS git-clang-format.bat
+    DESTINATION "${CMAKE_INSTALL_BINDIR}"
+    COMPONENT clang-format)
+endif()
diff --git a/clang/tools/clang-format/git-clang-format.bat b/clang/tools/clang-format/git-clang-format.bat
new file mode 100644
index 000000000000000..d4bc5172989cb09
--- /dev/null
+++ b/clang/tools/clang-format/git-clang-format.bat
@@ -0,0 +1 @@
+py -3 git-clang-format %*

[owenca]

This allows git-clang-format to be used on a Windows terminal without manually needing to find the path and invoke the python interpreter. We have a similar script for scan-build.

Can you open an issue and link to it from here? It seems git clang-format works in Command Prompt without this new batch file.

[llvm-beanz]

Can you open an issue and link to it from here?

Filed #69643.

It seems git clang-format works in Command Prompt without this new batch file.

IIUC, git clang-format works if you have WSL installed, but not with a default Windows installation. We definitely have users on my team that are Windows-only users who encounter an error running that command even if the git-clang-format script is on the path, and the presence of the .bat file solves the issue.

[owenca]

@mydeveloperday what do you think?

[HazardyKnusperkeks]

What is py? I have no program called py on my machine (Windows with msys2), so you would possibly break that? Why not write python or python3?

[llvm-beanz]

py.exe is the Windows python launcher. It comes with Python for Windows (not msys2 or cygwin where the shebang line would work). It is the Windows way of choosing which python version you want. You need to use this approach because the standard Python for Windows install always installs python.exe regardless of version because Windows generally doesn't version binaries.

[1] Python for Windows docs
[2] Microsoft docs

I'm going to go take a long shower now to try and forget that I learned this much about Windows.

[owenca]

@llvm-beanz This doesn't seem to work if git-clang-format is run from another directory:

C:\Users\Owen\llvm-project>clang\tools\clang-format\git-clang-format

C:\Users\Owen\llvm-project>py -3 git-clang-format
C:\Users\Owen\AppData\Local\Programs\Python\Python39\python.exe: can't open file 'C:\Users\Owen\llvm-project\git-clang-format': [Errno 2] No such file or directory

C:\Users\Owen\llvm-project>

[HazardyKnusperkeks]

I have no real opinion on this matter, as I don't use that program/script. But when it helps the windows users, why not? I also see no harm.

[owenca]

See #75268.