[clang] bdbdf74 - [clang][AST] Add an AST matcher for deducedTemplateSpeializationType.

[Haojian Wu via cfe-commits]

Author: Haojian Wu
Date: 2020-02-03T12:11:44+01:00
New Revision: bdbdf748225525bb18cd0ffeb51c3e713f7b8e1b

URL: https://github.com/llvm/llvm-project/commit/bdbdf748225525bb18cd0ffeb51c3e713f7b8e1b
DIFF: https://github.com/llvm/llvm-project/commit/bdbdf748225525bb18cd0ffeb51c3e713f7b8e1b.diff

LOG: [clang][AST] Add an AST matcher for deducedTemplateSpeializationType.

Summary:
misc-unused-using clang-tidy check needs this matcher to fix a false
positive of C++17 deduced class template types.

Reviewers: gribozavr2

Reviewed By: gribozavr2

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73869

Added: 
    

Modified: 
    clang/docs/LibASTMatchersReference.html
    clang/include/clang/ASTMatchers/ASTMatchers.h
    clang/lib/ASTMatchers/Dynamic/Registry.cpp
    clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp

Removed: 
    


################################################################################
diff  --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
index 95328dcd82eb..3d2ff477853f 100644
--- a/clang/docs/LibASTMatchersReference.html
+++ b/clang/docs/LibASTMatchersReference.html
@@ -1750,6 +1750,20 @@ <h2 id="decl-matchers">Node Matchers</h2>
 </pre></td></tr>
 
 
+<tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1Type.html">Type</a>></td><td class="name" onclick="toggle('deducedTemplateSpecializationType0')"><a name="deducedTemplateSpecializationType0Anchor">deducedTemplateSpecializationType</a></td><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1DeducedTemplateSpecializationType.html">DeducedTemplateSpecializationType</a>>...</td></tr>
+<tr><td colspan="4" class="doc" id="deducedTemplateSpecializationType0"><pre>Matches C++17 deduced template specialization types, e.g. deduced class
+template types.
+
+Given
+  template <typename T>
+  class C { public: C(T); };
+
+  C c(123);
+deducedTemplateSpecializationType() matches the type in the declaration
+of the variable c.
+</pre></td></tr>
+
+
 <tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1Type.html">Type</a>></td><td class="name" onclick="toggle('dependentSizedArrayType0')"><a name="dependentSizedArrayType0Anchor">dependentSizedArrayType</a></td><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1DependentSizedArrayType.html">DependentSizedArrayType</a>>...</td></tr>
 <tr><td colspan="4" class="doc" id="dependentSizedArrayType0"><pre>Matches C++ arrays whose size is a value-dependent expression.
 
@@ -3522,7 +3536,7 @@ <h2 id="narrowing-matchers">Narrowing Matchers</h2>
 </pre></td></tr>
 
 
-<tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1NamedDecl.html">NamedDecl</a>></td><td class="name" onclick="toggle('hasName0')"><a name="hasName0Anchor">hasName</a></td><td>const std::string  Name</td></tr>
+<tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1NamedDecl.html">NamedDecl</a>></td><td class="name" onclick="toggle('hasName0')"><a name="hasName0Anchor">hasName</a></td><td>StringRef Name</td></tr>
 <tr><td colspan="4" class="doc" id="hasName0"><pre>Matches NamedDecl nodes that have the specified name.
 
 Supports specifying enclosing namespaces or classes by prefixing the name

diff  --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
index 4fdbf3e3ba6e..2bd24ef4cf6b 100644
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -6030,6 +6030,21 @@ extern const AstTypeMatcher<EnumType> enumType;
 extern const AstTypeMatcher<TemplateSpecializationType>
     templateSpecializationType;
 
+/// Matches C++17 deduced template specialization types, e.g. deduced class
+/// template types.
+///
+/// Given
+/// \code
+///   template <typename T>
+///   class C { public: C(T); };
+///
+///   C c(123);
+/// \endcode
+/// \c deducedTemplateSpecializationType() matches the type in the declaration
+/// of the variable \c c.
+extern const AstTypeMatcher<DeducedTemplateSpecializationType>
+    deducedTemplateSpecializationType;
+
 /// Matches types nodes representing unary type transformations.
 ///
 /// Given:

diff  --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index 8c6dcfaaf52f..7344c622cc9d 100644
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -202,6 +202,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(declStmt);
   REGISTER_MATCHER(declaratorDecl);
   REGISTER_MATCHER(decltypeType);
+  REGISTER_MATCHER(deducedTemplateSpecializationType);
   REGISTER_MATCHER(defaultStmt);
   REGISTER_MATCHER(dependentSizedArrayType);
   REGISTER_MATCHER(designatedInitExpr);

diff  --git a/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
index 1fdaf66f285c..b603d764e3a6 100644
--- a/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
@@ -1458,6 +1458,12 @@ TEST(TypeMatching, MatchesTemplateSpecializationType) {
                       templateSpecializationType()));
 }
 
+TEST(TypeMatching, MatchesDeucedTemplateSpecializationType) {
+  EXPECT_TRUE(matches("template <typename T> class A{ public: A(T) {} }; A a(1);",
+                      deducedTemplateSpecializationType(),
+                      LanguageMode::Cxx17OrLater));
+}
+
 TEST(TypeMatching, MatchesRecordType) {
   EXPECT_TRUE(matches("class C{}; C c;", recordType()));
   EXPECT_TRUE(matches("struct S{}; S s;",