[PATCH] D54349: [clang-tidy] new check 'readability-redundant-preprocessor'

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added a comment.

What do you think about code like:

  #if FOO == 4
  #if FOO == 4
  #endif
  #endif
  
  #if defined(FOO)
  #if defined(FOO)
  #endif
  #endif
  
  #if !defined(FOO)
  #if !defined(FOO)
  #endif
  #endif
  
  #if defined(FOO)
  #if !defined(FOO)
  #endif
  #endif
  
  #if !defined(FOO)
  #if defined(FOO)
  #endif
  #endif



================
Comment at: clang-tidy/readability/CMakeLists.txt:23
   ReadabilityTidyModule.cpp
+  RedundantPreprocessorCheck.cpp
   RedundantControlFlowCheck.cpp
----------------
Please keep this list sorted alphabetically.


================
Comment at: clang-tidy/readability/RedundantPreprocessorCheck.cpp:52
+private:
+  void Startif(SourceLocation Loc, const Token &MacroNameTok,
+               SmallVector<Entry, 4> &Stack, StringRef Warning,
----------------
This name is not particularly descriptive. This seems to be more like `CheckMacroRedundancy` or something like that?


================
Comment at: clang-tidy/readability/RedundantPreprocessorCheck.h:1-2
+//===--- RedundantPreprocessorCheck.h - clang-tidy -----------------------*- C++
+//-*-===//
+//
----------------
This comment should be re-flowed to fit the column width.


================
Comment at: clang-tidy/readability/RedundantPreprocessorCheck.h:20
+
+/// This check flags redundant preprocessor usage.
+///
----------------
What constitutes "redundancy"? A bit more exposition here would be useful.


https://reviews.llvm.org/D54349