Started making simplifyKnownVariables(), but it is very much unfinished. Two test cases added for it.

testtokenize.cpp

@@ -46,7 +46,9 @@ private:
 
         TEST_CASE( const_and_volatile_functions );
 
-        TEST_CASE( numeric_true_condition );
+        TEST_CASE( numeric_true_condition );
+
+        TEST_CASE( simplify_known_variables );
 
         TEST_CASE( multi_compare );
 
@@ -216,6 +218,51 @@ private:
             ostr << " " << tok->str();
         ASSERT_EQUALS( std::string(" void f ( ) { if ( true ) ; }"), ostr.str() );
     }
+
+    void simplify_known_variables()
+    {
+        {
+            const char code[] = "void f()\n"
+                                "{\n"
+                                "    int a = 10;\n"
+                                "    if (a);\n"
+                                "}\n";
+
+            // tokenize..
+            Tokenizer tokenizer;
+            std::istringstream istr(code);
+            tokenizer.tokenize(istr, "test.cpp");
+
+            tokenizer.simplifyTokenList();
+
+            std::ostringstream ostr;
+            for (const TOKEN *tok = tokenizer.tokens(); tok; tok = tok->next())
+                ostr << " " << tok->str();
+            // TODO, the actual string should be " void f ( ) { int a ; a = 10 ; if ( true ) ; }"
+            ASSERT_EQUALS( std::string(" void f ( ) { int a ; a = 10 ; if ( a ) ; }"), ostr.str() );
+        }
+
+        {
+            const char code[] = "void f()\n"
+                                "{\n"
+                                "    int a = 10;\n"
+                                "    a = g();\n"
+                                "    if (a);\n"
+                                "}\n";
+
+            // tokenize..
+            Tokenizer tokenizer;
+            std::istringstream istr(code);
+            tokenizer.tokenize(istr, "test.cpp");
+
+            tokenizer.simplifyTokenList();
+
+            std::ostringstream ostr;
+            for (const TOKEN *tok = tokenizer.tokens(); tok; tok = tok->next())
+                ostr << " " << tok->str();
+            ASSERT_EQUALS( std::string(" void f ( ) { int a ; a = 10 ; a = g ( ) ; if ( a ) ; }"), ostr.str() );
+        }
+    }
 
     void multi_compare()
     {

tokenize.cpp

@@ -1175,8 +1175,23 @@ bool Tokenizer::simplifyFunctionReturn()
     return ret;
 }
 
+bool Tokenizer::simplifyKnownVariables()
+{
+    // TODO, this function should be called from simplifyTokenList()
+    // after the implementation is done.
+    // TODO, this functions needs to be implemented.
+    // TODO, test
+    bool ret = false;
+    for ( const TOKEN *tok = tokens(); tok; tok = tok->next() )
+    {
+        if ( TOKEN::Match(tok, "%var% = %num% ;") )
+        {
 
+        }
+    }
 
+    return ret;
+}
 
 //---------------------------------------------------------------------------
 // Helper functions for handling the tokens list

tokenize.h

@@ -112,6 +112,16 @@ private:
      *         false if nothing is done.
      */
     bool simplifyFunctionReturn();
+
+    /**
+     * A simplify function that replaces a variable with its value in cases
+     * when the value is known. e.g. "x=10; if(x)" => "x=10;if(10)"
+     *
+     * @param token The token list to check and modify.
+     * @return true if modifications to token-list are done.
+     *         false if no modifications are done.
+     */
+    bool simplifyKnownVariables();
 
     TOKEN *_gettok(TOKEN *tok, int index);