Redundant condition : Added a check

Makefile

@@ -1,6 +1,6 @@
 SRCS=checkbufferoverrun.cpp	checkclass.cpp	checkheaders.cpp	checkmemoryleak.cpp	checkfunctionusage.cpp	checkother.cpp	filelister.cpp	preprocessor.cpp	tokenize.cpp	cppcheck.cpp	settings.cpp token.cpp cppcheckexecutor.cpp
 OBJS=$(SRCS:%.cpp=%.o)
-TESTS=testbufferoverrun.o	testcharvar.o	testclass.o	testconstructors.o	testdivision.o  testfunctionusage.o	testincompletestatement.o	testmemleak.o	testpreprocessor.o	testsimplifytokens.o	testtokenize.o	testtoken.o	testunusedprivfunc.o	testunusedvar.o	testfilelister.o
+TESTS=testbufferoverrun.o	testcharvar.o	testclass.o	testconstructors.o	testdivision.o  testfunctionusage.o	testincompletestatement.o	testmemleak.o	testpreprocessor.o	testredundantif.o	testsimplifytokens.o	testtokenize.o	testtoken.o	testunusedprivfunc.o	testunusedvar.o	testfilelister.o
 BIN = ${DESTDIR}/usr/bin
 
 all:	${OBJS} main.o
@@ -49,6 +49,8 @@ testmemleak.o: testmemleak.cpp tokenize.h settings.h errorlogger.h token.h check
 	g++ -Wall -pedantic -g -I. -o $@ -c $*.cpp
 testpreprocessor.o: testpreprocessor.cpp testsuite.h errorlogger.h preprocessor.h
 	g++ -Wall -pedantic -g -I. -o $@ -c $*.cpp
+testredundantif.o: testredundantif.cpp testsuite.h errorlogger.h checkother.h
+	g++ -Wall -pedantic -g -I. -o $@ -c $*.cpp
 testrunner.o: testrunner.cpp testsuite.h errorlogger.h
 	g++ -Wall -pedantic -g -I. -o $@ -c $*.cpp
 testsimplifytokens.o: testsimplifytokens.cpp testsuite.h errorlogger.h tokenize.h settings.h token.h

checkother.cpp

@@ -203,14 +203,49 @@ void CheckOther::WarningRedundantCode()
         }
     }
 
-
-    // TODO: Redundant condition
+
+
+    // Redundant condition
     // if (haystack.find(needle) != haystack.end())
-    //    haystack.remove(needle);
-
+    //    haystack.remove(needle);
+    redundantCondition2();
 }
 //---------------------------------------------------------------------------
 
+void CheckOther::redundantCondition2()
+{
+    const char pattern[] = "if ( %var% . find ( %any% ) != %var% . end ( ) )"
+                           "{|{|"
+                           "    %var% . remove ( %any% ) ;"
+                           "}|}|";
+    const TOKEN *tok = TOKEN::findmatch( _tokenizer->tokens(), pattern );
+    while ( tok )
+    {
+        bool b = TOKEN::Match( tok->tokAt(15), "{" );
+
+        // Get tokens for the fields %var% and %any%
+        const TOKEN *var1 = tok->tokAt(2);
+        const TOKEN *any1 = tok->tokAt(6);
+        const TOKEN *var2 = tok->tokAt(9);
+        const TOKEN *var3 = tok->tokAt(b ? 16 : 15);
+        const TOKEN *any2 = tok->tokAt(b ? 20 : 19);
+        
+        // Check if all the "%var%" fields are the same and if all the "%any%" are the same..
+        if (var1->str() == var2->str() && 
+            var2->str() == var3->str() && 
+            any1->str() == any2->str() )
+        {
+            std::ostringstream errmsg;
+            errmsg << _tokenizer->fileLine(tok) 
+                   << ": Redundant condition found. The remove function in the STL will not do anything if element doesn't exist";
+            _errorLogger->reportErr(errmsg.str());
+        }
+
+        tok = TOKEN::findmatch( tok->next(), pattern );
+    }
+}
+//---------------------------------------------------------------------------
+
 
 
 

checkother.h

@@ -75,10 +75,18 @@ public:
     void unreachableCode();
 
     /** Unused function variables */
-    void functionVariableUsage();
-private:
+    void functionVariableUsage();
+    
+#ifndef UNIT_TESTING
+private:
+#endif
     void CheckVariableScope_LookupVar( const TOKEN *tok1, const char varname[] );
-
+
+    // Redundant condition
+    // if (haystack.find(needle) != haystack.end())
+    //    haystack.remove(needle);
+    void redundantCondition2();
+
     const Tokenizer *_tokenizer;
     ErrorLogger *_errorLogger;
 };

testredundantif.cpp

@@ -0,0 +1,87 @@
+/*
+ * c++check - c/c++ syntax checking
+ * Copyright (C) 2007 Daniel Marjamäki
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/
+ */
+
+
+// Check for dangerous division..
+// such as "svar / uvar". Treating "svar" as unsigned data is not good
+
+
+#define UNIT_TESTING
+#include "tokenize.h"
+#include "checkother.h"
+#include "testsuite.h"
+
+#include <sstream>
+
+extern std::ostringstream errout;
+
+class TestRedundantIf : public TestFixture
+{
+public:
+    TestRedundantIf() : TestFixture("TestRedundantIf")
+    { }
+
+private:
+    void check( const char code[] )
+    {
+        // Tokenize..
+        Tokenizer tokenizer;
+        std::istringstream istr(code);
+        tokenizer.tokenize( istr, "test.cpp" );
+
+        // Clear the error buffer..
+        errout.str("");
+
+        // Check for redundant condition..
+        CheckOther checkOther( &tokenizer, this );
+        checkOther.redundantCondition2();
+    }
+
+    void run()
+    {
+        // TODO TEST_CASE( remove1 );
+        // TODO TEST_CASE( remove2 );
+    }
+
+    void remove1()
+    {
+        check( "void f()\n"
+               "{\n"
+               "    if (haystack.find(needle) != haystack.end())\n"
+               "        haystack.remove(needle);"
+               "}\n" );
+        ASSERT_EQUALS( std::string("[test.cpp:3]: Redundant condition.\n"), errout.str() );
+    }
+
+    void remove2()
+    {
+        check( "void f()\n"
+               "{\n"
+               "    if (haystack.find(needle) != haystack.end())\n"
+               "    {\n"
+               "        haystack.remove(needle);\n"
+               "    }\n"
+               "}\n" );
+        ASSERT_EQUALS( std::string("[test.cpp:3]: Redundant condition.\n"), errout.str() );
+    }
+
+};
+
+REGISTER_TEST( TestRedundantIf )
+
+