added environment variable UNUSEDFUNCTION_ONLY to make sure only the unusedFunction check is being executed (#4362)

Author: firewave

.github/workflows/selfcheck.yml

@@ -78,6 +78,7 @@ jobs:
           ./cppcheck -q --template=selfcheck --error-exitcode=1 --library=cppcheck-lib --library=qt -D__CPPCHECK__ -D__GNUC__ -DQT_VERSION=0x050000 -DQ_MOC_OUTPUT_REVISION=67 --enable=unusedFunction --exception-handling -rp=. --project=cmake.output/compile_commands.json --suppressions-list=.selfcheck_unused_suppressions --inline-suppr
         env:
           DISABLE_VALUEFLOW: 1
+          UNUSEDFUNCTION_ONLY: 1
 
       # the following steps are duplicated from above since setting up the build node in a parallel step takes longer than the actual steps
       - name: CMake (no test)
@@ -98,6 +99,7 @@ jobs:
           ./cppcheck -q --template=selfcheck --error-exitcode=1 --library=cppcheck-lib --library=qt -D__CPPCHECK__ -D__GNUC__ -DQT_VERSION=0x050000 -DQ_MOC_OUTPUT_REVISION=67 --enable=unusedFunction --exception-handling -rp=. --project=cmake.output.notest/compile_commands.json --suppressions-list=.selfcheck_unused_suppressions --inline-suppr
         env:
           DISABLE_VALUEFLOW: 1
+          UNUSEDFUNCTION_ONLY: 1
 
       - name: Fetch corpus
         run: |
@@ -126,6 +128,7 @@ jobs:
           head -50 callgrind.annotated.log
         env:
           DISABLE_VALUEFLOW: 1
+          UNUSEDFUNCTION_ONLY: 1
 
       - uses: actions/upload-artifact@v2
         with:

lib/cppcheck.cpp

@@ -1025,6 +1025,10 @@ void CppCheck::checkRawTokens(const Tokenizer &tokenizer)
 
 void CppCheck::checkNormalTokens(const Tokenizer &tokenizer)
 {
+    // TODO: this should actually be the behavior if only "--enable=unusedFunction" is specified - see #10648
+    const char* unusedFunctionOnly = std::getenv("UNUSEDFUNCTION_ONLY");
+    const bool doUnusedFunctionOnly = unusedFunctionOnly && (std::strcmp(unusedFunctionOnly, "1") == 0);
+
     // call all "runChecks" in all registered Check classes
     for (Check *check : Check::instances()) {
         if (Settings::terminated())
@@ -1033,6 +1037,9 @@ void CppCheck::checkNormalTokens(const Tokenizer &tokenizer)
         if (Tokenizer::isMaxTime())
             return;
 
+        if (doUnusedFunctionOnly && dynamic_cast<CheckUnusedFunctions*>(check) == nullptr)
+            continue;
+
         Timer timerRunChecks(check->name() + "::runChecks", mSettings.showtime, &s_timerResults);
         check->runChecks(&tokenizer, &mSettings, this);
     }
@@ -1053,7 +1060,10 @@ void CppCheck::checkNormalTokens(const Tokenizer &tokenizer)
                 mAnalyzerInformation.setFileInfo("ctu", fi1->toString());
         }
 
-        for (const Check *check: Check::instances()) {
+        for (const Check *check : Check::instances()) {
+            if (doUnusedFunctionOnly && dynamic_cast<const CheckUnusedFunctions*>(check) == nullptr)
+                continue;
+
             Check::FileInfo *fi = check->getFileInfo(&tokenizer, &mSettings);
             if (fi != nullptr) {
                 if (mSettings.jobs == 1)