Fix #10059 missing varId with using namespace (#3860)

* Fix #10059 missing varId with using namespace

* Undo

* Fix test

* Limit namespace candidates, duplicateBranch

* rvalue ref

* Undo

* Undo

* Undo

* Format

* Fix condition

lib/tokenize.cpp

@@ -4243,7 +4243,8 @@ void Tokenizer::setVarIdPass2()
                 tok = tok->next();
             else if (Token::Match(tok->previous(), "!!:: %name% <") && Token::Match(tok->next()->findClosingBracket(),"> :: ~| %name%"))
                 tok = tok->next()->findClosingBracket()->next();
-            else
+            else if (usingnamespaces.empty() || tok->varId() || !tok->isName() || tok->isStandardType() || tok->tokType() == Token::eKeyword || tok->tokType() == Token::eBoolean ||
+                     Token::Match(tok->previous(), ".|namespace|class|struct|&|&&|*|> %name%") || Token::Match(tok->previous(), "%type%| %name% ( %type%|)") || Token::Match(tok, "public:|private:|protected:"))
                 continue;
 
             while (Token::Match(tok, ":: ~| %name%")) {

test/testnullpointer.cpp

@@ -3589,7 +3589,7 @@ private:
               "    stringstream out;\n"
               "    out << ((ip >> 0) & 0xFF);\n"
               "    return out.str();\n"
-              "}n", true);
+              "}", true);
         ASSERT_EQUALS("", errout.str());
         // avoid regression from first fix attempt for #5811...
         check("void deserialize(const std::string &data) {\n"

test/testsimplifytokens.cpp

@@ -344,6 +344,7 @@ private:
         TEST_CASE(simplifyKnownVariablesGlobalVars);
         TEST_CASE(simplifyKnownVariablesReturn);   // 3500 - return
         TEST_CASE(simplifyKnownVariablesPointerAliasFunctionCall); // #7440
+        TEST_CASE(simplifyKnownVariablesNamespace); // #10059
 
         TEST_CASE(simplifyCasts1);
         TEST_CASE(simplifyCasts2);
@@ -6874,6 +6875,31 @@ private:
         ASSERT_EQUALS(exp, tokenizeAndStringify(code, /*simplify=*/ true));
     }
 
+    void simplifyKnownVariablesNamespace() { // #10059
+        const char code[] = "namespace N {\n"
+                            "    const int n = 0;\n"
+                            "    namespace M { const int m = 0; }\n"
+                            "}\n"
+                            "using namespace N;\n"
+                            "int i(n);\n"
+                            "int j(M::m);\n"
+                            "using namespace N::M;\n"
+                            "int k(m);\n"
+                            "int l(N::M::m);\n";
+        const char exp[]  = "\n\n##file 0\n"
+                            "1: namespace N {\n"
+                            "2: const int n@1 = 0 ;\n"
+                            "3: namespace M { const int m@2 = 0 ; }\n"
+                            "4: }\n"
+                            "5: using namespace N ;\n"
+                            "6: int i ; i = n@1 ;\n"
+                            "7: int j ( M :: m@2 ) ;\n"
+                            "8: using namespace N :: M ;\n"
+                            "9: int k ; k = m@2 ;\n"
+                            "10: int l ( N :: M :: m@2 ) ;\n";
+        ASSERT_EQUALS(exp, tokenizeDebugListing(code));
+    }
+
     void simplifyKnownVariablesClassMember() {
         // Ticket #2815
         {