[PATCH] D44517: [change-namespace] Don't match a function call/ref multiple times.

[Eric Liu via Phabricator via cfe-commits]

ioeric created this revision.
ioeric added a reviewer: hokein.
Herald added subscribers: cfe-commits, klimek.

Previously, the matcher matches a function call/ref multiple times, one
for each decl ancestor. This might cause problems. For example, in the following
case, `func()` would be matched once (with namespace context) before using decl is
seen and once after using decl is seeing, which would result in different conflicting
replacements as the first match would replace `func` with "ns::func" as it doesn't
know about the using decl.

  namespace x {
  namespace {
  using ::ns::func;
  void f() { func(); }
  }
  }

Switching from `hasDescendant` matching to `hasAncestor` matching solves the
problem.


Repository:
  rCTE Clang Tools Extra

https://reviews.llvm.org/D44517

Files:
  change-namespace/ChangeNamespace.cpp
  unittests/change-namespace/ChangeNamespaceTests.cpp


Index: unittests/change-namespace/ChangeNamespaceTests.cpp
===================================================================
--- unittests/change-namespace/ChangeNamespaceTests.cpp
+++ unittests/change-namespace/ChangeNamespaceTests.cpp
@@ -850,22 +850,58 @@
 TEST_F(ChangeNamespaceTest, UsingShadowDeclInGlobal) {
   std::string Code = "namespace glob {\n"
                      "class Glob {};\n"
+                     "void GFunc() {}\n"
                      "}\n"
                      "using glob::Glob;\n"
+                     "using glob::GFunc;\n"
                      "namespace na {\n"
                      "namespace nb {\n"
-                     "void f() { Glob g; }\n"
+                     "void f() { Glob g; GFunc(); }\n"
                      "} // namespace nb\n"
                      "} // namespace na\n";
 
   std::string Expected = "namespace glob {\n"
                          "class Glob {};\n"
+                         "void GFunc() {}\n"
                          "}\n"
                          "using glob::Glob;\n"
+                         "using glob::GFunc;\n"
                          "\n"
                          "namespace x {\n"
                          "namespace y {\n"
-                         "void f() { Glob g; }\n"
+                         "void f() { Glob g; GFunc(); }\n"
+                         "} // namespace y\n"
+                         "} // namespace x\n";
+  EXPECT_EQ(format(Expected), runChangeNamespaceOnCode(Code));
+}
+
+TEST_F(ChangeNamespaceTest, UsingShadowDeclsInAnonymousNamespaces) {
+  std::string Code = "namespace util {\n"
+                     "class Util {};\n"
+                     "void func() {}\n"
+                     "}\n"
+                     "namespace na {\n"
+                     "namespace nb {\n"
+                     "namespace {\n"
+                     "using ::util::Util;\n"
+                     "using ::util::func;\n"
+                     "void f() { Util u; func(); }\n"
+                     "}\n"
+                     "} // namespace nb\n"
+                     "} // namespace na\n";
+
+  std::string Expected = "namespace util {\n"
+                         "class Util {};\n"
+                         "void func() {}\n"
+                         "} // namespace util\n"
+                         "\n"
+                         "namespace x {\n"
+                         "namespace y {\n"
+                         "namespace {\n"
+                         "using ::util::Util;\n"
+                         "using ::util::func;\n"
+                         "void f() { Util u; func(); }\n"
+                         "}\n"
                          "} // namespace y\n"
                          "} // namespace x\n";
   EXPECT_EQ(format(Expected), runChangeNamespaceOnCode(Code));
Index: change-namespace/ChangeNamespace.cpp
===================================================================
--- change-namespace/ChangeNamespace.cpp
+++ change-namespace/ChangeNamespace.cpp
@@ -478,13 +478,13 @@
                                 hasAncestor(namespaceDecl(isAnonymous())),
                                 hasAncestor(cxxRecordDecl()))),
                    hasParent(namespaceDecl()));
-  Finder->addMatcher(decl(forEachDescendant(expr(anyOf(
-                              callExpr(callee(FuncMatcher)).bind("call"),
-                              declRefExpr(to(FuncMatcher.bind("func_decl")))
-                                  .bind("func_ref")))),
-                          IsInMovedNs, unless(isImplicit()))
-                         .bind("dc"),
-                     this);
+  Finder->addMatcher(
+      expr(allOf(hasAncestor(decl().bind("dc")), IsInMovedNs,
+                 unless(hasAncestor(isImplicit())),
+                 anyOf(callExpr(callee(FuncMatcher)).bind("call"),
+                       declRefExpr(to(FuncMatcher.bind("func_decl")))
+                           .bind("func_ref")))),
+      this);
 
   auto GlobalVarMatcher = varDecl(
       hasGlobalStorage(), hasParent(namespaceDecl()),
@@ -509,6 +509,7 @@
 void ChangeNamespaceTool::run(
     const ast_matchers::MatchFinder::MatchResult &Result) {
   if (const auto *Using = Result.Nodes.getNodeAs<UsingDecl>("using")) {
+                 << Using->getQualifiedNameAsString() << "\n";
     UsingDecls.insert(Using);
   } else if (const auto *UsingNamespace =
                  Result.Nodes.getNodeAs<UsingDirectiveDecl>(


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D44517.138549.patch
Type: text/x-patch
Size: 4428 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20180315/dc0ca036/attachment-0001.bin>