[clang-tidy] Silent warning instead of an error when readability-identifier-naming cannot parse a .clang-tidy file

[carlosgalvezp]

Consider this example:

$ cat main.cpp
#include "foo.h"

$ cat include/foo.h
#define poorNamedMacro

$ cat include/.clang-tidy
InvalidOption

$ cat .clang-tidy 
CheckOptions: {
  readability-identifier.naming.MacroDefinitionCase: UPPER_CASE
}

Running clang-tidy:

$ clang-tidy -checks=-*,readability-identifier-naming main.cpp -header-filter=.*  -- -I include/
/tmp/include/.clang-tidy:1:1: error: not a mapping
InvalidOption
^~~~~~~~~~~~~
Error parsing /tmp/include/.clang-tidy: Invalid argument

$ echo $?
0

The .clang-tidy file in the include folder has invalid syntax. readability-identifier-naming picks up this file when processing a warning from a header next to it. However it does not make clang-tidy fail with an error upon parse failure, like clang-tidy would do with the "main" .clang-tidy file.

[llvmbot]

@llvm/issue-subscribers-clang-tidy

Author: Carlos Galvez (carlosgalvezp)

Consider this example:

$ cat main.cpp
#include "foo.h"

$ cat include/foo.h
#define poorNamedMacro

$ cat include/.clang-tidy
InvalidOption

$ cat .clang-tidy 
CheckOptions: {
  readability-identifier.naming.MacroDefinitionCase: UPPER_CASE
}

Running clang-tidy:

$ clang-tidy -checks=-*,readability-identifier-naming main.cpp -header-filter=.*  -- -I include/
/tmp/include/.clang-tidy:1:1: error: not a mapping
InvalidOption
^~~~~~~~~~~~~
Error parsing /tmp/include/.clang-tidy: Invalid argument

$ echo $?
0

The .clang-tidy file in the include folder has invalid syntax. readability-identifier-naming picks up this file when processing a warning from a header next to it. However it does not make clang-tidy fail with an error upon parse failure, like clang-tidy would do with the "main" .clang-tidy file.

[vbvictor]

Should it happen with other checks or only with readability-identifier-naming?
To me its general parsing mechanic so it should happen with other checks (Didn't check "identifier-naming" code, maybe I'm wrong)

[carlosgalvezp]

readability-identifier-naming is special - it's the only check that picks up the .clang-tidy file located next to the header which is included in a .cpp file. All other checks use the .clang-tidy file closest to the .cpp file at hand (also for analyzing its transitive includes).

The problem I describe does not happen for other checks, because the validation of the .clang-tidy file is done at startup. However the validation in readability-identifier-naming happens deep down in the execution, for example inside the MacroDefined callback.