[CLI] Fix double clang-tidy config flags

`clang-tidy` can be given config options via --analyzer-config and
-config in --tidyargs. --analyzer-config also has a default value, so in
case --tidyargs also contains a -config flag then both is given to
clang-tidy which thus fails.

analyzer/codechecker_analyzer/analyzers/clangtidy/analyzer.py

@@ -330,6 +330,23 @@ def construct_config_handler(cls, args, context):
                 if m.group('analyzer') == cls.ANALYZER_NAME:
                     analyzer_config[m.group('key')] = m.group('value')
 
+        # If both --analyzer-config and -config (in --tidyargs) is given then
+        # these need to be merged. Since "HeaderFilterRegex" has a default
+        # value in --analyzer-config, we take --tidyargs stronger so user can
+        # overwrite its value.
+        for i, extra_arg in enumerate(handler.analyzer_extra_arguments):
+            if extra_arg.startswith('-config'):
+                if extra_arg == '-config':
+                    arg = handler.analyzer_extra_arguments[i + 1]
+                    arg_num = 2
+                else:
+                    arg = extra_arg[len('-config='):]
+                    arg_num = 1
+
+                analyzer_config.update(json.loads(arg))
+                del handler.analyzer_extra_arguments[i:i + arg_num]
+                break
+
         # TODO: This extra "isinsrance" check is needed for
         # CodeChecker checkers --checker-config. This command also
         # runs this function in order to construct a config handler.

analyzer/tests/functional/analyze/test_analyze.py

@@ -509,6 +509,7 @@ def test_tidyargs_saargs(self):
         out, _ = process.communicate()
 
         self.assertIn("division by zero", out)
+        self.assertIn("modernize-avoid-bind", out)
 
         analyze_cmd = [self._codechecker_cmd, "analyze", build_json,
                        "-o", report_dir, "--saargs", saargs_file]

analyzer/tests/functional/analyze/test_files/tidyargs

@@ -1 +1 @@
---extra-arg=-DTIDYARGS
+--extra-arg=-DTIDYARGS '-config={"Checks": "modernize-*"}'