ASTMatcher for isMoveAssignmentOperator

[jbcoe]

Summary

Add ASTMatcher for isMoveAssignmentOperator as I need it for a 'rule-of-5' clang-tidy check.

Add tests and registration for clang-query.

[aaron.ballman]

LGTM!

[jbcoe]

Please merge to trunk if you are happy.

[aaron.ballman]

Thanks! I've commit in r258573

docs/LibASTMatchersReference.html

 </pre></td></tr>
 
 
+<tr><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1CXXMethodDecl.html">CXXMethodDecl</a>&gt;</td><td class="name" onclick="toggle('isMoveAssignmentOperator0')"><a name="isMoveAssignmentOperator0Anchor">isMoveAssignmentOperator</a></td><td></td></tr>
+<tr><td colspan="4" class="doc" id="isMoveAssignmentOperator0"><pre>Matches if the given method declaration declares a move assignment
+operator.
+
+Given
+struct A {
+  A &amp;operator=(const A &amp;);
+  A &amp;operator=(A &amp;&amp;);
+};
+
+cxxMethodDecl(isMoveAssignmentOperator()) matches the second method but not
+the first one.
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1CXXMethodDecl.html">CXXMethodDecl</a>&gt;</td><td class="name" onclick="toggle('isOverride0')"><a name="isOverride0Anchor">isOverride</a></td><td></td></tr>
 <tr><td colspan="4" class="doc" id="isOverride0"><pre>Matches if the given method declaration overrides another method.
 

include/clang/ASTMatchers/ASTMatchers.h

   return Node.isCopyAssignmentOperator();
 }
 
+/// \brief Matches if the given method declaration declares a move assignment
+/// operator.
+///
+/// Given
+/// \code
+///   struct S {
+///     S(const S &); // #1
+///     S& operator=(S &&); // #2
+///   };
+/// \endcode
+/// cxxMethodDecl(isMoveAssignmentOperator()) will match #2, but not #1.
+AST_MATCHER(CXXMethodDecl, isMoveAssignmentOperator) {
+  return Node.isMoveAssignmentOperator();
+}
+
 /// \brief Matches if the given method declaration overrides another method.
 ///
 /// Given

lib/ASTMatchers/Dynamic/Registry.cpp

   REGISTER_MATCHER(isInTemplateInstantiation);
   REGISTER_MATCHER(isListInitialization);
   REGISTER_MATCHER(isMemberInitializer);
+  REGISTER_MATCHER(isMoveAssignmentOperator);
   REGISTER_MATCHER(isMoveConstructor);
   REGISTER_MATCHER(isNoThrow);
   REGISTER_MATCHER(isOverride);

unittests/ASTMatchers/ASTMatchersTest.cpp

                       cxxMethodDecl(isCopyAssignmentOperator())));
 }
 
+TEST(Matcher, MatchesMoveAssignmentOperator) {
+  EXPECT_TRUE(notMatches("class X { X &operator=(X); };",
+                         cxxMethodDecl(isMoveAssignmentOperator())));
+  EXPECT_TRUE(matches("class X { X &operator=(X &&); };",
+                      cxxMethodDecl(isMoveAssignmentOperator())));
+  EXPECT_TRUE(matches("class X { X &operator=(const X &&); };",
+                      cxxMethodDecl(isMoveAssignmentOperator())));
+  EXPECT_TRUE(matches("class X { X &operator=(volatile X &&); };",
+                      cxxMethodDecl(isMoveAssignmentOperator())));
+  EXPECT_TRUE(matches("class X { X &operator=(const volatile X &&); };",
+                      cxxMethodDecl(isMoveAssignmentOperator())));
+  EXPECT_TRUE(notMatches("class X { X &operator=(X &); };",
+                         cxxMethodDecl(isMoveAssignmentOperator())));
+}
+
 TEST(Matcher, MatchesConstMethod) {
   EXPECT_TRUE(
       matches("struct A { void foo() const; };", cxxMethodDecl(isConst())));