Fix #12538 valueFlowBailoutIncompleteVar with nested enum (#6220)

Author: chrchr-github

lib/symboldatabase.cpp

@@ -5209,6 +5209,21 @@ const Token * Scope::addEnum(const Token * tok)
     return tok2;
 }
 
+static const Scope* findEnumScopeInBase(const Scope* scope, const std::string& tokStr)
+{
+    if (scope->definedType) {
+        const std::vector<Type::BaseInfo>& derivedFrom = scope->definedType->derivedFrom;
+        for (const Type::BaseInfo& i : derivedFrom) {
+            const Type *derivedFromType = i.type;
+            if (derivedFromType && derivedFromType->classScope) {
+                if (const Scope* enumScope = derivedFromType->classScope->findRecordInNestedList(tokStr))
+                    return enumScope;
+            }
+        }
+    }
+    return nullptr;
+}
+
 const Enumerator * SymbolDatabase::findEnumerator(const Token * tok, std::set<std::string>& tokensThatAreNotEnumeratorValues) const
 {
     if (tok->isKeyword())
@@ -5242,6 +5257,8 @@ const Enumerator * SymbolDatabase::findEnumerator(const Token * tok, std::set<st
                     temp = scope->nestedIn->findRecordInNestedList(tok1->str());
                 if (!temp && scope->functionOf)
                     temp = scope->functionOf->findRecordInNestedList(tok1->str());
+                if (!temp)
+                    temp = findEnumScopeInBase(scope, tok1->str());
                 if (temp) {
                     scope = temp;
                     break;

test/testsymboldatabase.cpp

@@ -447,6 +447,7 @@ class TestSymbolDatabase : public TestFixture {
         TEST_CASE(enum13);
         TEST_CASE(enum14);
         TEST_CASE(enum15);
+        TEST_CASE(enum16);
 
         TEST_CASE(sizeOfType);
 
@@ -6220,7 +6221,6 @@ class TestSymbolDatabase : public TestFixture {
             std::advance(it, 2);
             const Enumerator* E0 = it->findEnumerator("E0");
             ASSERT(E0 && E0->value_known && E0->value == 0);
-            std::advance(it, 1);
             const Token* const e = Token::findsimplematch(tokenizer.tokens(), "E0 ;");
             ASSERT(e && e->enumerator());
             ASSERT_EQUALS(E0, e->enumerator());
@@ -6289,6 +6289,29 @@ class TestSymbolDatabase : public TestFixture {
         }
     }
 
+    void enum16() {
+        {
+            GET_SYMBOL_DB("struct B {\n" // #12538
+                          "    struct S {\n"
+                          "        enum E { E0 = 0 };\n"
+                          "    };\n"
+                          "};\n"
+                          "struct D : B {\n"
+                          "    S::E f() const {\n"
+                          "        return S::E0;\n"
+                          "    }\n"
+                          "};\n");
+            ASSERT(db != nullptr);
+            auto it = db->scopeList.begin();
+            std::advance(it, 3);
+            const Enumerator* E0 = it->findEnumerator("E0");
+            ASSERT(E0 && E0->value_known && E0->value == 0);
+            const Token* const e = Token::findsimplematch(tokenizer.tokens(), "E0 ;");
+            ASSERT(e && e->enumerator());
+            ASSERT_EQUALS(E0, e->enumerator());
+        }
+    }
+
     void sizeOfType() {
         // #7615 - crash in Symboldatabase::sizeOfType()
         GET_SYMBOL_DB("enum e;\n"