fix #10335 (Type alias remains unknown with using) (#3323)

Co-authored-by: Robert Reif <reif@FX6840>

Author: IOBYTE

lib/tokenize.cpp

@@ -2368,7 +2368,15 @@ bool Tokenizer::simplifyUsing()
 
         std::string scope1 = currentScope1->fullName;
         bool skip = false; // don't erase type aliases we can't parse
+        Token *enumOpenBrace = nullptr;
         for (Token* tok1 = startToken; !skip && tok1 && tok1 != endToken; tok1 = tok1->next()) {
+            // skip enum body
+            if (tok1 && tok1 == enumOpenBrace) {
+                tok1 = tok1->link();
+                enumOpenBrace = nullptr;
+                continue;
+            }
+
             if ((Token::Match(tok1, "{|}|namespace|class|struct|union") && tok1->strAt(-1) != "using") ||
                 Token::Match(tok1, "using namespace %name% ;|::")) {
                 setScopeInfo(tok1, &currentScope1);
@@ -2389,12 +2397,15 @@ bool Tokenizer::simplifyUsing()
                 continue;
             }
 
-            // skip enum definitions
-            if (tok1->str() == "enum")
-                skipEnumBody(&tok1);
-
-            if (!tok1)
-                break;
+            // check for enum with body
+            if (tok1->str() == "enum") {
+                Token *defStart = tok1;
+                while (Token::Match(defStart, "%name%|::|:"))
+                    defStart = defStart->next();
+                if (Token::simpleMatch(defStart, "{"))
+                    enumOpenBrace = defStart;
+                continue;
+            }
 
             // check for member function and adjust scope
             if (isMemberFunction(tok1)) {

test/testsimplifyusing.cpp

@@ -90,6 +90,7 @@ class TestSimplifyUsing : public TestFixture {
         TEST_CASE(simplifyUsing10171);
         TEST_CASE(simplifyUsing10172);
         TEST_CASE(simplifyUsing10173);
+        TEST_CASE(simplifyUsing10335);
     }
 
     std::string tok(const char code[], bool simplify = true, Settings::PlatformType type = Settings::Native, bool debugwarnings = true) {
@@ -1304,6 +1305,13 @@ class TestSimplifyUsing : public TestFixture {
             ASSERT_EQUALS(exp, tok(code, true));
         }
     }
+
+    void simplifyUsing10335() {
+        const char code[] = "using uint8_t = unsigned char;\n"
+                            "enum E : uint8_t { E0 };";
+        const char exp[]  = "enum E : unsigned char { E0 } ;";
+        ASSERT_EQUALS(exp, tok(code, false));
+    }
 };
 
 REGISTER_TEST(TestSimplifyUsing)