[clang] Fix hasName matcher assertion with inline namespaces (PR #100975)

[Nathan James via cfe-commits]

https://github.com/njames93 created https://github.com/llvm/llvm-project/pull/100975

Fix handling of nodes which can be skipped in the fast path for the hasName matcher

#100973 

>From 8d1aeca42a0d544582823ff2bae0a217e14d1c02 Mon Sep 17 00:00:00 2001
From: Nathan James <n.james93 at hotmail.co.uk>
Date: Mon, 29 Jul 2024 07:21:53 +0100
Subject: [PATCH] Fix hasName matcher assertion with inline namespaces

Fix handling of nodes which can be skipped in the fast path for the
hasName matcher
---
 clang/lib/ASTMatchers/ASTMatchersInternal.cpp | 21 ++++++++++++-------
 .../ASTMatchers/ASTMatchersNarrowingTest.cpp  |  4 ++++
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
index bf87b1aa0992a..0556ae7ffae2f 100644
--- a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
+++ b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
@@ -537,14 +537,21 @@ class PatternSet {
   /// that didn't match.
   /// Return true if there are still any patterns left.
   bool consumeNameSuffix(StringRef NodeName, bool CanSkip) {
-    for (size_t I = 0; I < Patterns.size();) {
-      if (::clang::ast_matchers::internal::consumeNameSuffix(Patterns[I].P,
-                                                             NodeName) ||
-          CanSkip) {
-        ++I;
-      } else {
-        Patterns.erase(Patterns.begin() + I);
+    if (CanSkip) {
+      // If we can skip the node, then we need to handle the case where a
+      // skipped node has the same name as its parent.
+      // namespace a { inline namespace a { class A; } }
+      // cxxRecordDecl(hasName("::a::A")) 
+      // To do this, any patterns that match should be duplicated in our set, one of them with the tail removed.
+      for (size_t I = 0, E = Patterns.size(); I != E; ++I) {
+        StringRef Pattern = Patterns[I].P;
+        if (ast_matchers::internal::consumeNameSuffix(Patterns[I].P, NodeName))
+          Patterns.push_back({Pattern, Patterns[I].IsFullyQualified});
       }
+    } else {
+      llvm::erase_if(Patterns, [&NodeName](auto &Pattern) {
+        return !::clang::ast_matchers::internal::consumeNameSuffix(Pattern.P, NodeName);
+      });
     }
     return !Patterns.empty();
   }
diff --git a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
index f26140675fd46..611e1f9ba5327 100644
--- a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
@@ -2552,6 +2552,10 @@ TEST_P(ASTMatchersTest, HasName_MatchesNamespaces) {
                          recordDecl(hasName("a+b::C"))));
   EXPECT_TRUE(notMatches("namespace a { namespace b { class AC; } }",
                          recordDecl(hasName("C"))));
+  EXPECT_TRUE(matches("namespace a { inline namespace a { class C; } }",
+                      recordDecl(hasName("::a::C"))));
+  EXPECT_TRUE(matches("namespace a { inline namespace a { class C; } }",
+                      recordDecl(hasName("::a::a::C"))));
 }
 
 TEST_P(ASTMatchersTest, HasName_MatchesOuterClasses) {