[ASTMatchers] Introduce Objective-C matchers `hasReceiver` and `isInstanceMessage` for ObjCMessageExpr

[aaron.ballman]

clang/include/clang/ASTMatchers/ASTMatchers.h

2746

missing semicolon at the end of the statement?

2750

missing semicolon at the end of the statement?

2762

missing semicolon at the end of the statement?

2768

getInstanceReceiver() can return null, so you need a nullptr check before calling ignore paren imp casts.

clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp

610

Spurious newline can be removed.

[george.karpenkov]

Addressed comments.

[aaron.ballman]

LGTM aside from a style nit (you can take it or leave it).

clang/include/clang/ASTMatchers/ASTMatchers.h

2769

I'd drop the != nullptr bit.

clang/docs/LibASTMatchersReference.html

 
  matcher = objCMessageExpr(matchesSelector(hasUnarySelector());
  matches self.bodyView in the code below, but NOT the outer message
  invocation of "loadHTMLString:baseURL:".
     [self.bodyView loadHTMLString:html baseURL:NULL];
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ObjCMessageExpr.html">ObjCMessageExpr</a>&gt;</td><td class="name" onclick="toggle('isInstanceMessage0')"><a name="isInstanceMessage0Anchor">isInstanceMessage</a></td><td></td></tr>
+<tr><td colspan="4" class="doc" id="isInstanceMessage0"><pre>Returns true when the Objective-C message is sent to an instance.
+
+Example
+matcher = objcMessagaeExpr(isInstanceMessage())
+matches
+  NSString *x = @"hello";
+  [x containsString:@"h"]
+but not
+  [NSString stringWithFormat:@"format"]
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ObjCMessageExpr.html">ObjCMessageExpr</a>&gt;</td><td class="name" onclick="toggle('matchesSelector0')"><a name="matchesSelector0Anchor">matchesSelector</a></td><td>std::string RegExp</td></tr>
 <tr><td colspan="4" class="doc" id="matchesSelector0"><pre>Matches ObjC selectors whose name contains
 a substring matched by the given RegExp.
  matcher = objCMessageExpr(matchesSelector("loadHTMLStringmatches the outer message expr in the code below, but NOT the message
  invocation for self.bodyView.
     [self.bodyView loadHTMLString:html baseURL:NULL];
 </pre></td></tr>
 

 call expression.
 
 Example matches y in x(y)
     (matcher = callExpr(hasArgument(0, declRefExpr())))
   void x(int) { int y; x(y); }
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ObjCMessageExpr.html">ObjCMessageExpr</a>&gt;</td><td class="name" onclick="toggle('hasReceiver0')"><a name="hasReceiver0Anchor">hasReceiver</a></td><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1Expr.html">Expr</a>&gt; InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="hasReceiver0"><pre>Matches if the Objective-C message is sent to an instance,
+and the inner matcher matches on that instance.
+
+For example the method call in
+  NSString *x = @"hello";
+  [x containsString:@"h"]
+is matched by
+objcMessageExpr(hasReceiver(declRefExpr(to(varDecl(hasName("x"))))))
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ObjCMessageExpr.html">ObjCMessageExpr</a>&gt;</td><td class="name" onclick="toggle('hasReceiverType0')"><a name="hasReceiverType0Anchor">hasReceiverType</a></td><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1QualType.html">QualType</a>&gt; InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="hasReceiverType0"><pre>Matches on the receiver of an ObjectiveC Message expression.
 
 Example
 matcher = objCMessageExpr(hasReceiverType(asString("UIWebView *")));
 matches the [webView ...] message invocation.
   NSString *webViewJavaScript = ...
   UIWebView *webView = ...

clang/include/clang/ASTMatchers/ASTMatchers.h

 ///   [webView stringByEvaluatingJavaScriptFromString:webViewJavascript];
 /// \endcode
 AST_MATCHER_P(ObjCMessageExpr, hasReceiverType, internal::Matcher<QualType>,
               InnerMatcher) {
   const QualType TypeDecl = Node.getReceiverType();
   return InnerMatcher.matches(TypeDecl, Finder, Builder);
 }
 
+/// Returns true when the Objective-C message is sent to an instance.
+///
+/// Example
+/// matcher = objcMessagaeExpr(isInstanceMessage())
+/// matches
+/// \code
+///   NSString *x = @"hello";
+///   [x containsString:@"h"]
+/// \endcode
+/// but not
+/// \code
+///   [NSString stringWithFormat:@"format"]
+/// \endcode
+AST_MATCHER(ObjCMessageExpr, isInstanceMessage) {
+  return Node.isInstanceMessage();
+}
+
+/// Matches if the Objective-C message is sent to an instance,
+/// and the inner matcher matches on that instance.
+///
+/// For example the method call in
+/// \code
+///   NSString *x = @"hello";
+///   [x containsString:@"h"]
+/// \endcode
+/// is matched by
+/// objcMessageExpr(hasReceiver(declRefExpr(to(varDecl(hasName("x"))))))
+AST_MATCHER_P(ObjCMessageExpr, hasReceiver, internal::Matcher<Expr>,
+              InnerMatcher) {
+  const Expr *ReceiverNode = Node.getInstanceReceiver()->IgnoreParenImpCasts();
+  return (ReceiverNode != nullptr &&
+          InnerMatcher.matches(*ReceiverNode, Finder, Builder));
+}
+
 /// Matches when BaseName == Selector.getAsString()
 ///
 ///  matcher = objCMessageExpr(hasSelector("loadHTMLString:baseURL:"));
 ///  matches the outer message expr in the code below, but NOT the message
 ///  invocation for self.bodyView.
 /// \code
 ///     [self.bodyView loadHTMLString:html baseURL:NULL];
 /// \endcode

clang/lib/ASTMatchers/Dynamic/Registry.cpp

RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(hasNullSelector);
   REGISTER_MATCHER(hasObjectExpression);
   REGISTER_MATCHER(hasOperatorName);
   REGISTER_MATCHER(hasOverloadedOperatorName);
   REGISTER_MATCHER(hasParameter);
   REGISTER_MATCHER(hasParent);
   REGISTER_MATCHER(hasQualifier);
   REGISTER_MATCHER(hasRangeInit);
+  REGISTER_MATCHER(hasReceiver);
   REGISTER_MATCHER(hasReceiverType);
   REGISTER_MATCHER(hasReplacementType);
   REGISTER_MATCHER(hasReturnValue);
   REGISTER_MATCHER(hasRHS);
   REGISTER_MATCHER(hasSelector);
   REGISTER_MATCHER(hasAnySelector);
   REGISTER_MATCHER(hasSingleDecl);
   REGISTER_MATCHER(hasSize);
RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(isExplicitTemplateSpecialization);
   REGISTER_MATCHER(isExpr);
   REGISTER_MATCHER(isExternC);
   REGISTER_MATCHER(isFinal);
   REGISTER_MATCHER(isInline);
   REGISTER_MATCHER(isImplicit);
   REGISTER_MATCHER(isExpansionInFileMatching);
   REGISTER_MATCHER(isExpansionInMainFile);
+  REGISTER_MATCHER(isInstanceMessage);
   REGISTER_MATCHER(isInstantiated);
   REGISTER_MATCHER(isExpansionInSystemHeader);
   REGISTER_MATCHER(isInteger);
   REGISTER_MATCHER(isIntegral);
   REGISTER_MATCHER(isInTemplateInstantiation);
   REGISTER_MATCHER(isLambda);
   REGISTER_MATCHER(isListInitialization);
   REGISTER_MATCHER(isMemberInitializer);

clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp

EXPECT_FALSE(matchesObjC("@interface I -(void)f:(int) z; @end "
                            ObjCCallArgumentY));
   EXPECT_TRUE(notMatches("void x(int, int) { x(1, 2); }", CallArgumentY));
 
   StatementMatcher ImplicitCastedArgument = callExpr(
     hasAnyArgument(implicitCastExpr()));
   EXPECT_TRUE(matches("void x(long) { int y; x(y); }", ImplicitCastedArgument));
 }
 
+TEST(Matcher, HasReceiver) {
+  EXPECT_TRUE(matchesObjC(
+      "@interface NSString @end"
+      "void f(NSString *x) {"
+      "[x containsString]"
+      "}",
+      objcMessageExpr(hasReceiver(declRefExpr(to(varDecl(hasName("x"))))))));
+
+  EXPECT_FALSE(matchesObjC(
+      "@interface NSString +(NSString *) stringWithFormat; @end"
+      "void f() { [NSString stringWithFormat]; }",
+      objcMessageExpr(hasReceiver(declRefExpr(to(varDecl(hasName("x"))))))));
+}
+
+TEST(Matcher, isInstanceMessage) {
+  EXPECT_TRUE(matchesObjC(
+      "@interface NSString @end"
+      "void f(NSString *x) {"
+      "[x containsString]"
+      "}",
+      objcMessageExpr(isInstanceMessage())));
+
+  EXPECT_FALSE(matchesObjC(
+      "@interface NSString +(NSString *) stringWithFormat; @end"
+      "void f() { [NSString stringWithFormat]; }",
+      objcMessageExpr(isInstanceMessage())));
+
+}
+
 TEST(ForEachArgumentWithParam, ReportsNoFalsePositives) {
   StatementMatcher ArgumentY =
     declRefExpr(to(varDecl(hasName("y")))).bind("arg");
   DeclarationMatcher IntParam = parmVarDecl(hasType(isInteger())).bind("param");
   StatementMatcher CallExpr =
     callExpr(forEachArgumentWithParam(ArgumentY, IntParam));
 
   // IntParam does not match.
EXPECT_TRUE(matches(
     "class Y {}; class X { void x(Y y, X x) {} };",
     cxxMethodDecl(hasAnyParameter(hasType(recordDecl(hasName("X")))))));
   EXPECT_TRUE(matchesObjC("@interface I -(void)f:(int) x; @end",
                           objcMethodDecl(hasAnyParameter(hasName("x")))));
   EXPECT_TRUE(matchesObjC("int main() { void (^b)(int) = ^(int p) {}; }",
                           blockDecl(hasAnyParameter(hasName("p")))));
 }
 
+
 TEST(Returns, MatchesReturnTypes) {
   EXPECT_TRUE(matches("class Y { int f() { return 1; } };",
                       functionDecl(returns(asString("int")))));
   EXPECT_TRUE(notMatches("class Y { int f() { return 1; } };",
                          functionDecl(returns(asString("float")))));
   EXPECT_TRUE(matches("class Y { Y getMe() { return *this; } };",
                       functionDecl(returns(hasDeclaration(
                         recordDecl(hasName("Y")))))));