replaced some std::ostringstream usage with std::to_string() (#4719)

Author: firewave

cli/processexecutor.cpp

@@ -272,9 +272,7 @@ unsigned int ProcessExecutor::check()
                     resultOfCheck = fileChecker.check(iFile->first);
                 }
 
-                std::ostringstream oss;
-                oss << resultOfCheck;
-                pipewriter.writeEnd(oss.str());
+                pipewriter.writeEnd(std::to_string(resultOfCheck));
                 std::exit(EXIT_SUCCESS);
             }
 

lib/templatesimplifier.cpp

@@ -32,7 +32,6 @@
 #include <iostream>
 #include <map>
 #include <memory>
-#include <sstream> // IWYU pragma: keep
 #include <stack>
 #include <utility>
 
@@ -2422,9 +2421,7 @@ void TemplateSimplifier::simplifyTemplateArgs(Token *start, Token *end)
                     tok->deleteNext();
                     tok->deleteThis();
                     tok->deleteNext();
-                    std::ostringstream sz;
-                    sz << 1;
-                    tok->str(sz.str());
+                    tok->str(std::to_string(1));
                     again = true;
                 }
 
@@ -2433,9 +2430,7 @@ void TemplateSimplifier::simplifyTemplateArgs(Token *start, Token *end)
                     tok->deleteNext();
                     tok->deleteThis();
                     tok->deleteNext();
-                    std::ostringstream ostr;
-                    ostr << (Token::getStrLength(tok) + 1);
-                    tok->str(ostr.str());
+                    tok->str(std::to_string(Token::getStrLength(tok) + 1));
                     again = true;
                 }
 

test/testsuite.cpp

@@ -213,11 +213,7 @@ bool TestFixture::assertEquals(const char * const filename, const unsigned int l
 bool TestFixture::assertEquals(const char * const filename, const unsigned int linenr, const long long expected, const long long actual, const std::string &msg) const
 {
     if (expected != actual) {
-        std::ostringstream ostr1;
-        ostr1 << expected;
-        std::ostringstream ostr2;
-        ostr2 << actual;
-        assertEquals(filename, linenr, ostr1.str(), ostr2.str(), msg);
+        assertEquals(filename, linenr, std::to_string(expected), std::to_string(actual), msg);
     }
     return expected == actual;
 }
@@ -260,11 +256,7 @@ void TestFixture::todoAssertEquals(const char* const filename, const unsigned in
 
 void TestFixture::todoAssertEquals(const char * const filename, const unsigned int linenr, const long long wanted, const long long current, const long long actual) const
 {
-    std::ostringstream wantedStr, currentStr, actualStr;
-    wantedStr << wanted;
-    currentStr << current;
-    actualStr << actual;
-    todoAssertEquals(filename, linenr, wantedStr.str(), currentStr.str(), actualStr.str());
+    todoAssertEquals(filename, linenr, std::to_string(wanted), std::to_string(current), std::to_string(actual));
 }
 
 void TestFixture::assertThrow(const char * const filename, const unsigned int linenr) const