[PATCH] D25024: [clang-tidy] Add check for detecting declarations with multiple names

[Kirill Bobyrev via cfe-commits]

omtcyfz added inline comments.


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Comment at: clang-tidy/cppcoreguidelines/OneNamePerDeclarationCheck.cpp:38
+  diag(MultipleNameDeclaration->getStartLoc(),
+       "Do not declare multiple names per declaration");
+}
----------------
aaron.ballman wrote:
> Diagnostics do not start with a capital letter. Also, this diagnostic is not really accurate. Consider `void f(int x, int y);` -- that's a single declaration, but it declares multiple names. Perhaps: `do not declare more than one variable per declaration` since this should really be focusing on variable declarations rather than parameters, template parameter lists, etc
> Diagnostics do not start with a capital letter.

Clang SA diags do, actually. Though I can totally see the reason: consistency is important since it's clang-tidy check.

> Consider void f(int x, int y); -- that's a single declaration, but it declares multiple names. Perhaps: do not declare more than one variable per declaration since this should really be focusing on variable declarations rather than parameters, template parameter lists, etc

Fixed, thank you for the note!


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Comment at: test/clang-tidy/cppcoreguidelines-one-name-per-declaration.cpp:8
+  {
+    int x = 42, y = 43;
+    // CHECK-MESSAGES: :[[@LINE-1]]:5: warning: Do not declare multiple names per declaration [cppcoreguidelines-one-name-per-declaration]
----------------
malcolm.parsons wrote:
> The guideline says "Flag non-function arguments with multiple declarators involving declarator operators (e.g., int* p, q;)".
> 
> There are no declarator operators in this test, so there should be no warning.
The guideline says

> Reason: One-declaration-per line increases readability and avoids mistakes related to the C/C++ grammar. It also leaves room for a more descriptive end-of-line comment.

> Exception: a function declaration can contain several function argument declarations.

I'm not sure why what you copied is written in "Enforcement" section, but I do not think that is how it should be handled. I am concerned not only about that specific case and I see no reason to cut off cases already presented in this test.


https://reviews.llvm.org/D25024