[clang-tidy] add option to avoid "no checks enabled" error

[HerrCai0907]

When clang-tidy get an empty checks, it will throw "no checks enabled" error and exit with non-zero return value.
It make clang-tidy's wrapper program confused when in big project some files don't want to be checked and use -checks=-* to disable all checks.

[llvmbot]

@llvm/pr-subscribers-clang-tools-extra

@llvm/pr-subscribers-clang-tidy

Author: Congcong Cai (HerrCai0907)

Changes

When clang-tidy get an empty checks, it will throw "no checks enabled" error and exit with non-zero return value.
It make clang-tidy's wrapper program confused when in big project some files don't want to be checked and use -checks=-* to disable all checks.

---

Full diff: https://github.com/llvm/llvm-project/pull/96122.diff

2 Files Affected:

• (modified) clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp (+10-2)
• (modified) clang-tools-extra/docs/ReleaseNotes.rst (+3)

diff --git a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp index 7388f20ef288e..b579aff4394c9 100644 --- a/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp +++ b/clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp @@ -325,6 +325,14 @@ option is recognized. )"), cl::init(false), cl::cat(ClangTidyCategory)); +static cl::opt<bool> AllowEmptyCheckList("allow-empty-checks", desc(R"( +Allow empty enabled checks. This suppresses +the "no checks enabled" error when disabling +all of the checks. +)"), + cl::init(false), + cl::cat(ClangTidyCategory)); + namespace clang::tidy { static void printStats(const ClangTidyStats &Stats) { @@ -598,7 +606,7 @@ int clangTidyMain(int argc, const char **argv) { } if (ListChecks) { - if (EnabledChecks.empty()) { + if (EnabledChecks.empty() && !AllowEmptyCheckList) { llvm::errs() << "No checks enabled.\n"; return 1; } @@ -651,7 +659,7 @@ int clangTidyMain(int argc, const char **argv) { return 0; } - if (EnabledChecks.empty()) { + if (EnabledChecks.empty() && !AllowEmptyCheckList) { llvm::errs() << "Error: no checks enabled.\n"; llvm::cl::PrintHelpMessage(/*Hidden=*/false, /*Categorized=*/true); return 1; diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 3bdd735f7dcf7..54cfcafd121b6 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -125,6 +125,9 @@ Improvements to clang-tidy - Added argument `--exclude-header-filter` and config option `ExcludeHeaderFilterRegex` to exclude headers from analysis via a RegEx. +- Added argument `--allow-empty-checks` and config option `AllowEmptyCheckList` + to suppress "no checks enabled" error when disabling all of the checks. + New checks ^^^^^^^^^^ 

[PiotrZSL]

if a reason for this parameter is not to fail wrapper scripts, then maybe run-clang-tidy.py / run-clang-tidy-diff.py should also be updated.

[HerrCai0907]

if a reason for this parameter is not to fail wrapper scripts, then maybe run-clang-tidy.py / run-clang-tidy-diff.py should also be updated.

Both of them is fine because they only count the failed file and don't do any check about failure.

[5chmidti]

´run-clang-tidy.pyandclang-tidy-diff.py` should probably expose an option to enable this option via the script (maybe with an adjustment to the release notes).

[5chmidti]

I think it would be better to exit clang-tidy at this point, when there are no checks present and AllowNoChecks is enabled. The current behavior of this PR for invoking clang-tidy to check a file would be:

• if no checks are enabled and AllowNoChecks is true
  • continue executing clang-tidy even though no checks are enabled

I think it should be:

• if no checks are enabled
  • if AllowNoChecks is true then return 0, else error out with return 1

[5chmidti]

missing newline

[5chmidti]

the same should probably be done for diff-clang-tidy.py

[HerrCai0907]

Where is diff-clang-tidy.py?

[HerrCai0907]

I found it. It is named clang-tidy-diff.py

[5chmidti]

LGTM