Run Code Analysis on Active File should trigger code analysis only on the active file

[pramodkirchki]

Bug type: Language Service

Describe the bug

• OS and Version: Windows 10 Enterprise
• VS Code Version: 20H2
• C/C++ Extension Version: v1.10.7
• Description : Ctrl+Shift+P and run the option "C/C++: Run Code Analysis on Active File" triggers clang-tidy to run on the complete workspace instead of the active file.

Expected behavior
Run Code analysis on active file should trigger code analysis only on the active file

[pramodkirchki]

• Actually this might be an invalid issue.

• Clang-tidy runs on all the header files included in the cpp file. I don't know if this is configurable to not run on the inclusions but only on the cpp file.

• From clang-tidy documentation at https://releases.llvm.org/3.9.0/tools/clang/tools/extra/docs/clang-tidy/index.html, "Diagnostics from the main file of each translation unit are always displayed." is mentioned. So, the clang-tidy errors shown in problems window is from the translation unit and not only from the cpp file.

Then, it makes sense why we see problems from multiple header files.
Please invalidate the issue if you also think the same.

[sean-mcmanus]

This is currently "by design". The "active file" intentionally defaults to "active file and any headers included from the current workspace folder" under the assumption that those would be the preferred results for most scenarios. You can override that default by setting "C_Cpp.codeAnalysis.clangTidy.headerFilter": "" to get only issues for the actual file or set "C_Cpp.codeAnalysis.exclude": { "**/subFolder": true } to only exclude headers from certain subfolders.