ASTMatcher for ParenExpr node.

[adek05]

Summary

Simple matcher for parentheses in expressions.

Test Plan:
Unit tests. I also verified that the matcher can be used in clang-query.

[adek05]

Fix compilation error

[klimek]

include/clang/ASTMatchers/ASTMatchers.h

1051

Add '.' in the end.

1053–1054

I don't think the second half of the sentence is necessary - it is implied by saying what the example matches.

[adek05]

@klimek comments

[klimek]

LG

include/clang/ASTMatchers/ASTMatchers.h

1051

Ah, and s/parenthesis/parentheses/.

[adek05]

Would you mind committing it for me? I don't have repo access yet.

[adek05]

Fix typo

[LegalizeAdulthood]

Is the AST Matcher Reference page generated from the header and picks up this new matcher automatically or does the documentation also need an update?

[klimek]

In D16278#329491, @LegalizeAdulthood wrote:

Is the AST Matcher Reference page generated from the header and picks up this new matcher automatically or does the documentation also need an update?

Documentation also needs an update

[adek05]

Update online docs

[aaron.ballman]

I have a few small nits that don't require additional review.

include/clang/ASTMatchers/ASTMatchers.h

1052

Please use doxygen-style comments for the entire comment block.

unittests/ASTMatchers/ASTMatchersTest.cpp

3570

Please change this to EXPECT_TRUE and notMatches instead (for consistency in the rest of the file).

[adek05]

@aaron.ballman comments. If it looks good, please commit it for me :)

[aaron.ballman]

Thanks! I've commit in r258321

docs/LibASTMatchersReference.html

 
 The innermost message send invokes the "alloc" class method on the
 NSString class, while the outermost message send invokes the
 "initWithString" instance method on the object returned from
 NSString's "alloc". This matcher should match both message sends.
   [[NSString alloc] initWithString:@"Hello"]
 </pre></td></tr>
 
+<tr><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt;</td><td class="name" onclick="toggle('parenExpr0')"><a name="parenExpr0Anchor">parenExpr</a></td><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1ParenExpr.html">ParenExpr</a>&gt;...</td></tr>
+<tr><td colspan="4" class="doc" id="parenExpr0"><pre>Matches parentheses used in expressions.
+
+Given
+  int foo() { return 1; }
+  int a = (foo() + 1);
+matches '(foo() + 1)'
+</pre></td></tr>
 
 <tr><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt;</td><td class="name" onclick="toggle('returnStmt0')"><a name="returnStmt0Anchor">returnStmt</a></td><td>Matcher&lt<a href="http://clang.llvm.org/doxygen/classclang_1_1ReturnStmt.html">ReturnStmt</a>&gt;...</td></tr>
 <tr><td colspan="4" class="doc" id="returnStmt0"><pre>Matches return statements.
 
 Given
   return 1;
 returnStmt()
   matches 'return 1'

include/clang/ASTMatchers/ASTMatchers.h

 ///   };
 /// \endcode
 /// unresolvedUsingTypenameDecl()
 ///   matches \code using Base<T>::Foo \endcode
 const internal::VariadicDynCastAllOfMatcher<
   Decl,
   UnresolvedUsingTypenameDecl> unresolvedUsingTypenameDecl;
 
+/// \brief Matches parentheses used in expressions.
+///
+/// Example matches (foo() + 1)
+/// \code
+///   int foo() { return 1; }
+///   int a = (foo() + 1);
+/// \endcode
+const internal::VariadicDynCastAllOfMatcher<
+  Stmt,
+  ParenExpr> parenExpr;
+
 /// \brief Matches constructor call expressions (including implicit ones).
 ///
 /// Example matches string(ptr, n) and ptr within arguments of f
 ///     (matcher = cxxConstructExpr())
 /// \code
 ///   void f(const string &a, const string &b);
 ///   char *ptr;
 ///   int n;

lib/ASTMatchers/Dynamic/Registry.cpp

RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(numSelectorArgs);
   REGISTER_MATCHER(ofClass);
   REGISTER_MATCHER(objcInterfaceDecl);
   REGISTER_MATCHER(objcMessageExpr);
   REGISTER_MATCHER(objcObjectPointerType);
   REGISTER_MATCHER(on);
   REGISTER_MATCHER(onImplicitObjectArgument);
   REGISTER_MATCHER(parameterCountIs);
+  REGISTER_MATCHER(parenExpr);
   REGISTER_MATCHER(parenType);
   REGISTER_MATCHER(parmVarDecl);
   REGISTER_MATCHER(pointee);
   REGISTER_MATCHER(pointerType);
   REGISTER_MATCHER(qualType);
   REGISTER_MATCHER(recordDecl);
   REGISTER_MATCHER(recordType);
   REGISTER_MATCHER(referenceType);

unittests/ASTMatchers/ASTMatchersTest.cpp

TEST(ExceptionHandling, SimpleCases) {
   EXPECT_TRUE(notMatches("void foo() try { throw; } catch(int) { }",
                          cxxCatchStmt(isCatchAll())));
   EXPECT_TRUE(matches("void foo() try {} catch(int X) { }",
                       varDecl(isExceptionVariable())));
   EXPECT_TRUE(notMatches("void foo() try { int X; } catch (...) { }",
                          varDecl(isExceptionVariable())));
 }
 
+TEST(ParenExpression, SimpleCases) {
+  EXPECT_TRUE(matches("int i = (3);", parenExpr()));
+  EXPECT_TRUE(matches("int i = (3 + 7);", parenExpr()));
+  EXPECT_TRUE(notMatches("int i = 3;", parenExpr()));
+  EXPECT_TRUE(notMatches("int foo() { return 1; }; int a = foo();",
+                         parenExpr()));
+}
+
 TEST(HasConditionVariableStatement, DoesNotMatchCondition) {
   EXPECT_TRUE(notMatches(
       "void x() { if(true) {} }",
       ifStmt(hasConditionVariableStatement(declStmt()))));
   EXPECT_TRUE(notMatches(
       "void x() { int x; if((x = 42)) {} }",
       ifStmt(hasConditionVariableStatement(declStmt()))));
 }

unittests/ASTMatchers/Dynamic/RegistryTest.cpp

 TEST_F(RegistryTest, HasArgs) {
   Matcher<Decl> Value = constructMatcher(
       "decl", constructMatcher("hasAttr", StringRef("attr::WarnUnused")))
       .getTypedMatcher<Decl>();
   EXPECT_TRUE(matches("struct __attribute__((warn_unused)) X {};", Value));
   EXPECT_FALSE(matches("struct X {};", Value));
 }
 
+TEST_F(RegistryTest, ParenExpr) {
+  Matcher<Stmt> Value = constructMatcher("parenExpr").getTypedMatcher<Stmt>();
+  EXPECT_TRUE(matches("int i = (1);", Value));
+  EXPECT_FALSE(matches("int i = 1;", Value));
+}
+
 } // end anonymous namespace
 } // end namespace dynamic
 } // end namespace ast_matchers
 } // end namespace clang