Fix #13299: misra.py: use language attribute instead of file extensio…

…n to determine language

addons/cppcheckdata.py

@@ -1218,6 +1218,7 @@ def __init__(self, filename):
         """
         :param filename: Path to Cppcheck dump file
         """
+        self.language = None
         self.filename = filename
         self.rawTokens = []
         self.platform = None
@@ -1234,6 +1235,8 @@ def __init__(self, filename):
         for event, node in ElementTree.iterparse(self.filename, events=('start', 'end')):
             if platform_done and rawtokens_done and suppressions_done:
                 break
+            if node.tag == 'dumps':
+                self.language = node.get('language')
             if node.tag == 'platform' and event == 'start':
                 self.platform = Platform(node)
                 platform_done = True

addons/misra.py

@@ -4525,7 +4525,7 @@ def fillVerifyExpected(verify_expected, tok):
         else:
             self.printStatus('Checking ' + dumpfile + '...')
 
-        self.is_cpp = data.files and data.files[0].endswith('.cpp')
+        self.is_cpp = data.language == 'cpp'
 
         for cfgNumber, cfg in enumerate(data.iterconfigurations()):
             if not self.settings.quiet: