[clang-tidy] Add inconsistent declaration parameter name check

This is first of series of patches, porting code from my project colobot-lint,
as I mentioned recently in cfe-dev mailing list.

This patch adds a new check in readability module:
readability-inconsistent-declaration-parameter-name. I also added appropriate
testcases and documentation.

I chose readability module, as it seems it is the best place for it.

I think I followed the rules of LLVM coding guideline, but I may have missed
something, as I usually use other code formatting style.

http://reviews.llvm.org/D12462

Patch by Piotr Dziwinski!

llvm-svn: 247261

2 files changed, 33 insertions, 0 deletions

diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst
index abd5b8ef395..be7bf3b0f71 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -50,6 +50,7 @@ List of clang-tidy Checks
    readability-else-after-return
    readability-function-size
    readability-identifier-naming
+   readability-inconsistent-declaration-parameter-name
    readability-named-parameter
    readability-redundant-smartptr-get
    readability-redundant-string-cstr
diff --git a/clang-tools-extra/docs/clang-tidy/checks/readability-inconsistent-declaration-parameter-name.rst b/clang-tools-extra/docs/clang-tidy/checks/readability-inconsistent-declaration-parameter-name.rst
new file mode 100644
index 00000000000..872fee747da
--- /dev/null
+++ b/clang-tools-extra/docs/clang-tidy/checks/readability-inconsistent-declaration-parameter-name.rst
@@ -0,0 +1,32 @@
+readability-inconsistent-declaration-parameter-name
+===================================================
+
+
+Find function declarations which differ in parameter names.
+
+Example:
+
+.. code:: c++
+
+  // in foo.hpp:
+  void foo(int a, int b, int c);
+
+  // in foo.cpp:
+  void foo(int d, int e, int f); // warning
+
+This check should help to enforce consistency in large projects, where it often
+happens that a definition of function is refactored, changing the parameter
+names, but its declaration in header file is not updated. With this check, we
+can easily find and correct such inconsistencies, keeping declaration and
+definition always in sync.
+
+Unnamed parameters are allowed and are not taken into account when comparing
+function declarations, for example:
+
+.. code:: c++
+
+   void foo(int a);
+   void foo(int); // no warning
+
+If there are multiple declarations of same function, only one warning will be
+generated.