Implement new AST matcher hasAnyCapture to match on LambdaExpr captures.

Accepts child matchers cxxThisExpr to match on capture of this and also on varDecl.

diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
index 05562c5..5bb181b 100644 (file)
--- a/clang/docs/LibASTMatchersReference.html
+++ b/clang/docs/LibASTMatchersReference.html
@@ -6390,6 +6390,33 @@ Usable as: Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Addr
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1LambdaExpr.html">LambdaExpr</a>&gt;</td><td class="name" onclick="toggle('hasAnyCapture1')"><a name="hasAnyCapture1Anchor">hasAnyCapture</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXThisExpr.html">CXXThisExpr</a>&gt; InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="hasAnyCapture1"><pre>Matches any capture of 'this' in a lambda expression.
+
+Given
+  struct foo {
+    void bar() {
+      auto f = [this](){};
+    }
+  }
+lambdaExpr(hasAnyCapture(cxxThisExpr()))
+  matches [this](){};
+</pre></td></tr>
+
+
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1LambdaExpr.html">LambdaExpr</a>&gt;</td><td class="name" onclick="toggle('hasAnyCapture0')"><a name="hasAnyCapture0Anchor">hasAnyCapture</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1VarDecl.html">VarDecl</a>&gt; InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="hasAnyCapture0"><pre>Matches any capture of a lambda expression.
+
+Given
+  void foo() {
+    int x;
+    auto f = [x](){};
+  }
+lambdaExpr(hasAnyCapture(anything()))
+  matches [x](){};
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1MemberExpr.html">MemberExpr</a>&gt;</td><td class="name" onclick="toggle('hasDeclaration7')"><a name="hasDeclaration7Anchor">hasDeclaration</a></td><td>const Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Decl.html">Decl</a>&gt;  InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="hasDeclaration7"><pre>Matches a node if the declaration associated with that node
 matches the given matcher.
@@ -7277,6 +7304,10 @@ Usable as: Any Matcher
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;T&gt;</td><td class="name" onclick="toggle('traverse1')"><a name="traverse1Anchor">traverse</a></td><td>ast_type_traits::TraversalKind TK, const BindableMatcher&lt;T&gt;  InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="traverse1"><pre></pre></td></tr>
+
+
 <tr><td>Matcher&lt;T&gt;</td><td class="name" onclick="toggle('traverse0')"><a name="traverse0Anchor">traverse</a></td><td>ast_type_traits::TraversalKind TK, const Matcher&lt;T&gt;  InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="traverse0"><pre>Causes all nested matchers to be matched with the specified traversal kind.
 

diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
index 71cb852..9a5888b 100644 (file)
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -55,6 +55,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/ExprObjC.h"
+#include "clang/AST/LambdaCapture.h"
 #include "clang/AST/NestedNameSpecifier.h"
 #include "clang/AST/OpenMPClause.h"
 #include "clang/AST/OperationKinds.h"
@@ -4044,6 +4045,50 @@ AST_POLYMORPHIC_MATCHER_P(hasAnyArgument,
   return false;
 }
 
+/// Matches any capture of a lambda expression.
+///
+/// Given
+/// \code
+///   void foo() {
+///     int x;
+///     auto f = [x](){};
+///   }
+/// \endcode
+/// lambdaExpr(hasAnyCapture(anything()))
+///   matches [x](){};
+AST_MATCHER_P_OVERLOAD(LambdaExpr, hasAnyCapture, internal::Matcher<VarDecl>,
+                       InnerMatcher, 0) {
+  for (const LambdaCapture &Capture : Node.captures()) {
+    if (Capture.capturesVariable()) {
+      BoundNodesTreeBuilder Result(*Builder);
+      if (InnerMatcher.matches(*Capture.getCapturedVar(), Finder, &Result)) {
+        *Builder = std::move(Result);
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+/// Matches any capture of 'this' in a lambda expression.
+///
+/// Given
+/// \code
+///   struct foo {
+///     void bar() {
+///       auto f = [this](){};
+///     }
+///   }
+/// \endcode
+/// lambdaExpr(hasAnyCapture(cxxThisExpr()))
+///   matches [this](){};
+AST_MATCHER_P_OVERLOAD(LambdaExpr, hasAnyCapture,
+                       internal::Matcher<CXXThisExpr>, InnerMatcher, 1) {
+  return llvm::any_of(Node.captures(), [](const LambdaCapture &LC) {
+    return LC.capturesThis();
+  });
+}
+
 /// Matches a constructor call expression which uses list initialization.
 AST_MATCHER(CXXConstructExpr, isListInitialization) {
   return Node.isListInitialization();

diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index 475818b..1c0930c 100644 (file)
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -105,6 +105,7 @@ RegistryMaps::RegistryMaps() {
   // equalsNode
 
   REGISTER_OVERLOADED_2(callee);
+  REGISTER_OVERLOADED_2(hasAnyCapture);
   REGISTER_OVERLOADED_2(hasPrefix);
   REGISTER_OVERLOADED_2(hasType);
   REGISTER_OVERLOADED_2(ignoringParens);

diff --git a/clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp
index ee7b3bf..23447ba 100644 (file)
--- a/clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersTraversalTest.cpp
@@ -454,6 +454,26 @@ TEST(Matcher, HasReceiver) {
       objcMessageExpr(hasReceiver(declRefExpr(to(varDecl(hasName("x"))))))));
 }
 
+TEST(Matcher, HasAnyCapture) {
+  auto HasCaptureX = lambdaExpr(hasAnyCapture(varDecl(hasName("x"))));
+  EXPECT_TRUE(matches("void f() { int x = 3; [x](){}; }", HasCaptureX));
+  EXPECT_TRUE(matches("void f() { int x = 3; [&x](){}; }", HasCaptureX));
+  EXPECT_TRUE(notMatches("void f() { [](){}; }", HasCaptureX));
+  EXPECT_TRUE(notMatches("void f() { int z = 3; [&z](){}; }", HasCaptureX));
+  EXPECT_TRUE(
+      notMatches("struct a { void f() { [this](){}; }; };", HasCaptureX));
+}
+
+TEST(Matcher, CapturesThis) {
+  auto HasCaptureThis = lambdaExpr(hasAnyCapture(cxxThisExpr()));
+  EXPECT_TRUE(
+      matches("struct a { void f() { [this](){}; }; };", HasCaptureThis));
+  EXPECT_TRUE(notMatches("void f() { [](){}; }", HasCaptureThis));
+  EXPECT_TRUE(notMatches("void f() { int x = 3; [x](){}; }", HasCaptureThis));
+  EXPECT_TRUE(notMatches("void f() { int x = 3; [&x](){}; }", HasCaptureThis));
+  EXPECT_TRUE(notMatches("void f() { int z = 3; [&z](){}; }", HasCaptureThis));
+}
+
 TEST(Matcher, isClassMessage) {
   EXPECT_TRUE(matchesObjC(
       "@interface NSString +(NSString *) stringWithFormat; @end "