Make isDefinition matcher support ObjCMethodDecl

[kastiglione]

Summary

Allow the isDefinition() matcher to apply to ObjCMethodDecl nodes, in
addition to those it already supports. For whatever reason, ObjCMethodDecl
does not inherit from FunctionDecl and so this is specialization is necessary.

[aaron.ballman]

LGTM!

[kastiglione]

Update isDefinition comment docs to reflect addition of ObjCMethodDecl

[kastiglione]

Regenerate AST Matcher docs

docs/LibASTMatchersReference.html

 Given:
   class A { ~A(); };
   class B { ~B() = default; };
 functionDecl(isDefaulted())
   matches the declaration of ~B, but not ~A.
 </pre></td></tr>
 
 
-<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;</td><td class="name" onclick="toggle('isDefinition2')"><a name="isDefinition2Anchor">isDefinition</a></td><td></td></tr>
-<tr><td colspan="4" class="doc" id="isDefinition2"><pre>Matches if a declaration has a body attached.
+<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;</td><td class="name" onclick="toggle('isDefinition3')"><a name="isDefinition3Anchor">isDefinition</a></td><td></td></tr>
+<tr><td colspan="4" class="doc" id="isDefinition3"><pre>Matches if a declaration has a body attached.
 
 Example matches A, va, fa
   class A {};
   class B;  Doesn't match, as it has no body.
   int va;
   extern int vb;  Doesn't match, as it doesn't define the variable.
   void fa() {}
   void fb();  Doesn't match, as it has no body.
+  @interface X
+  - (void)ma; Doesn't match, interface is declaration.
+  @end
+  @implementation X
+  - (void)ma {}
+  @end
 
 Usable as: Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1TagDecl.html">TagDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;
 </pre></td></tr>
 
 
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;</td><td class="name" onclick="toggle('isDeleted0')"><a name="isDeleted0Anchor">isDeleted</a></td><td></td></tr>
 <tr><td colspan="4" class="doc" id="isDeleted0"><pre>Matches deleted function declarations.
 

 
  matcher = objCMessageExpr(numSelectorArgs(2));
  matches the invocation of "loadHTMLString:baseURL:" but not that
  of self.bodyView
     [self.bodyView loadHTMLString:html baseURL:NULL];
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ObjCMethodDecl.html">ObjCMethodDecl</a>&gt;</td><td class="name" onclick="toggle('isDefinition2')"><a name="isDefinition2Anchor">isDefinition</a></td><td></td></tr>
+<tr><td colspan="4" class="doc" id="isDefinition2"><pre>Matches if a declaration has a body attached.
+
+Example matches A, va, fa
+  class A {};
+  class B;  Doesn't match, as it has no body.
+  int va;
+  extern int vb;  Doesn't match, as it doesn't define the variable.
+  void fa() {}
+  void fb();  Doesn't match, as it has no body.
+  @interface X
+  - (void)ma; Doesn't match, interface is declaration.
+  @end
+  @implementation X
+  - (void)ma {}
+  @end
+
+Usable as: Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1TagDecl.html">TagDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1QualType.html">QualType</a>&gt;</td><td class="name" onclick="toggle('asString0')"><a name="asString0Anchor">asString</a></td><td>std::string Name</td></tr>
 <tr><td colspan="4" class="doc" id="asString0"><pre>Matches if the matched type is represented by the given string.
 
 Given
   class Y { public: void x(); };
   void z() { Y* y; y-&gt;x(); }
 cxxMemberCallExpr(on(hasType(asString("class Y *"))))
   matches y-&gt;x()

 
 Example matches A, va, fa
   class A {};
   class B;  Doesn't match, as it has no body.
   int va;
   extern int vb;  Doesn't match, as it doesn't define the variable.
   void fa() {}
   void fb();  Doesn't match, as it has no body.
+  @interface X
+  - (void)ma; Doesn't match, interface is declaration.
+  @end
+  @implementation X
+  - (void)ma {}
+  @end
 
 Usable as: Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1TagDecl.html">TagDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;
 </pre></td></tr>
 
 
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1TemplateArgument.html">TemplateArgument</a>&gt;</td><td class="name" onclick="toggle('equalsIntegralValue0')"><a name="equalsIntegralValue0Anchor">equalsIntegralValue</a></td><td>std::string Value</td></tr>
 <tr><td colspan="4" class="doc" id="equalsIntegralValue0"><pre>Matches a TemplateArgument of integral type with a given value.
 

 
 Example matches A, va, fa
   class A {};
   class B;  Doesn't match, as it has no body.
   int va;
   extern int vb;  Doesn't match, as it doesn't define the variable.
   void fa() {}
   void fb();  Doesn't match, as it has no body.
+  @interface X
+  - (void)ma; Doesn't match, interface is declaration.
+  @end
+  @implementation X
+  - (void)ma {}
+  @end
 
 Usable as: Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1TagDecl.html">TagDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;, Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;
 </pre></td></tr>
 
 
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt;</td><td class="name" onclick="toggle('isExceptionVariable0')"><a name="isExceptionVariable0Anchor">isExceptionVariable</a></td><td></td></tr>
 <tr><td colspan="4" class="doc" id="isExceptionVariable0"><pre>Matches a variable declaration that is an exception variable from
 a C++ catch block, or an Objective-C statement.

include/clang/ASTMatchers/ASTMatchers.h

 /// Example matches A, va, fa
 /// \code
 ///   class A {};
 ///   class B;  // Doesn't match, as it has no body.
 ///   int va;
 ///   extern int vb;  // Doesn't match, as it doesn't define the variable.
 ///   void fa() {}
 ///   void fb();  // Doesn't match, as it has no body.
+///   @interface X
+///   - (void)ma; // Doesn't match, interface is declaration.
+///   @end
+///   @implementation X
+///   - (void)ma {}
+///   @end
 /// \endcode
 ///
-/// Usable as: Matcher<TagDecl>, Matcher<VarDecl>, Matcher<FunctionDecl>
+/// Usable as: Matcher<TagDecl>, Matcher<VarDecl>, Matcher<FunctionDecl>,
+///   Matcher<ObjCMethodDecl>
 AST_POLYMORPHIC_MATCHER(isDefinition,
                         AST_POLYMORPHIC_SUPPORTED_TYPES(TagDecl, VarDecl,
+                                                        ObjCMethodDecl,
                                                         FunctionDecl)) {
   return Node.isThisDeclarationADefinition();
 }
 
 /// \brief Matches if a function declaration is variadic.
 ///
 /// Example matches f, but not g or h. The function i will not match, even when
 /// compiled in C mode.

unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp

DeclarationMatcher DefinitionOfVariableA =
     varDecl(hasName("a"), isDefinition());
   EXPECT_TRUE(matches("int a;", DefinitionOfVariableA));
   EXPECT_TRUE(notMatches("extern int a;", DefinitionOfVariableA));
 
   DeclarationMatcher DefinitionOfMethodA =
     cxxMethodDecl(hasName("a"), isDefinition());
   EXPECT_TRUE(matches("class A { void a() {} };", DefinitionOfMethodA));
   EXPECT_TRUE(notMatches("class A { void a(); };", DefinitionOfMethodA));
+
+  DeclarationMatcher DefinitionOfObjCMethodA =
+    objcMethodDecl(hasName("a"), isDefinition());
+  EXPECT_TRUE(matchesObjC("@interface A @end "
+                          "@implementation A; -(void)a {} @end",
+                          DefinitionOfObjCMethodA));
+  EXPECT_TRUE(notMatchesObjC("@interface A; - (void)a; @end",
+                             DefinitionOfObjCMethodA));
 }
 
 TEST(Matcher, HandlesNullQualTypes) {
   // FIXME: Add a Type matcher so we can replace uses of this
   // variable with Type(True())
   const TypeMatcher AnyType = anything();
 
   // We don't really care whether this matcher succeeds; we're testing that