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

[aaron.ballman]

clang/include/clang/ASTMatchers/ASTMatchers.h

2746 ↗

(On Diff #155543)

missing semicolon at the end of the statement?

2750 ↗

(On Diff #155543)

missing semicolon at the end of the statement?

2762 ↗

(On Diff #155543)

missing semicolon at the end of the statement?

2768 ↗

(On Diff #155543)

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

clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp

610 ↗

(On Diff #155543)

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 ↗

(On Diff #155734)

I'd drop the != nullptr bit.

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 = ...

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();
+  return (ReceiverNode != nullptr &&
+          InnerMatcher.matches(*ReceiverNode->IgnoreParenImpCasts(), 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

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);

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.