From 976921d4b4911394fe0e88b047a01dad5e85c701 Mon Sep 17 00:00:00 2001
From: Alexander Kornienko <alexfh@google.com>
Date: Tue, 22 Mar 2016 11:03:03 +0000
Subject: [PATCH] [ASTMatchers] New matcher hasReturnValue added
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Summary: A checker (will be uploaded after this patch) needs to check implicit casts. Existing generic matcher "has" ignores implicit casts and parenthesized expressions and no specific matcher for matching return value expression preexisted. The patch adds such a matcher (hasReturnValue).

Reviewers: klimek, sbenza

Subscribers: xazax.hun, klimek, cfe-commits

Patch by Ádám Balogh!

Differential Revision: http://reviews.llvm.org/D17986

llvm-svn: 264037
---
 clang/docs/LibASTMatchersReference.html         | 12 ++++++++++++
 clang/include/clang/ASTMatchers/ASTMatchers.h   | 16 ++++++++++++++++
 clang/lib/ASTMatchers/Dynamic/Registry.cpp      |  1 +
 clang/unittests/ASTMatchers/ASTMatchersTest.cpp |  6 ++++++
 4 files changed, 35 insertions(+)

diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
index ba3fa51b87b5..58ab6d12850f 100644
--- a/clang/docs/LibASTMatchersReference.html
+++ b/clang/docs/LibASTMatchersReference.html
@@ -4854,6 +4854,18 @@ Usable as: Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1Block
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1ReturnStmt.html">ReturnStmt</a>&gt;</td><td class="name" onclick="toggle('hasReturnValue0')"><a name="hasReturnValue0Anchor">hasReturnValue</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="hasReturnValue0"><pre>Matches the return value expression of a return statement
+
+Given
+  return a + b;
+hasReturnValue(binaryOperator())
+  matches 'return a + b'
+with binaryOperator()
+  matching 'a + b'
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1StmtExpr.html">StmtExpr</a>&gt;</td><td class="name" onclick="toggle('hasAnySubstatement1')"><a name="hasAnySubstatement1Anchor">hasAnySubstatement</a></td><td>Matcher&lt;<a href="http://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="hasAnySubstatement1"><pre>Matches compound statements where at least one substatement matches
 a given matcher. Also matches StmtExprs that have CompoundStmt as children.
diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
index e428d8c3957f..6835ea0871b5 100644
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -5008,6 +5008,22 @@ AST_MATCHER_P(Decl, hasAttr, attr::Kind, AttrKind) {
   return false;
 }
 
+/// \brief Matches the return value expression of a return statement
+///
+/// Given
+/// \code
+///   return a + b;
+/// \endcode
+/// hasReturnValue(binaryOperator())
+///   matches 'return a + b'
+/// with binaryOperator()
+///   matching 'a + b'
+AST_MATCHER_P(ReturnStmt, hasReturnValue, internal::Matcher<Expr>, 
+              InnerMatcher) {
+  return InnerMatcher.matches(*Node.getRetValue(), Finder, Builder);
+}
+
+
 /// \brief Matches CUDA kernel call expression.
 ///
 /// Example matches,
diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index 0a8e820d03d9..9bf57851adec 100644
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -243,6 +243,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(hasQualifier);
   REGISTER_MATCHER(hasRangeInit);
   REGISTER_MATCHER(hasReceiverType);
+  REGISTER_MATCHER(hasReturnValue);
   REGISTER_MATCHER(hasRHS);
   REGISTER_MATCHER(hasSelector);
   REGISTER_MATCHER(hasSingleDecl);
diff --git a/clang/unittests/ASTMatchers/ASTMatchersTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersTest.cpp
index 63dc1a8b6497..713ef5a84fee 100644
--- a/clang/unittests/ASTMatchers/ASTMatchersTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersTest.cpp
@@ -5488,5 +5488,11 @@ TEST(NullPointerConstants, Basic) {
   EXPECT_TRUE(notMatches("int i = 0;", expr(nullPointerConstant())));
 }
 
+TEST(StatementMatcher, HasReturnValue) {
+  StatementMatcher RetVal = returnStmt(hasReturnValue(binaryOperator()));
+  EXPECT_TRUE(matches("int F() { int a, b; return a + b; }", RetVal));
+  EXPECT_FALSE(matches("int F() { int a; return a; }", RetVal));
+}
+
 } // end namespace ast_matchers
 } // end namespace clang