addons/namingng.py: allow function/variable name test without prefixes (#5801)

This patch allows a config file to have RE_VARNAME and RE_FUNCTIONNAME
without the corresponding var_prefixes and function_prefixes keys. The
namingng.py processing function would otherwise raise an exception
trying to get these keys, while they are not strictly necessary, if no
prefixes are required.

Author: mvds00

addons/namingng.py

@@ -132,7 +132,7 @@ def process(dumpfiles, configfile, debugprint=False):
 
                         if conf["skip_one_char_variables"] and len(var.nameToken.str) == 1:
                             continue
-                        if varType in conf["var_prefixes"]:
+                        if varType in conf.get("var_prefixes",{}):
                             if not var.nameToken.str.startswith(conf["var_prefixes"][varType]):
                                 errors.append(reportError(
                                                     var.typeStartToken.file,
@@ -192,7 +192,7 @@ def process(dumpfiles, configfile, debugprint=False):
                         if debugprint:
                             print("\t:: {} {}".format(retval, token.function.name))
 
-                        if retval and retval in conf["function_prefixes"]:
+                        if retval and retval in conf.get("function_prefixes",{}):
                             if not token.function.name.startswith(conf["function_prefixes"][retval]):
                                 errors.append(reportError(
                                     token.file, token.linenr, 'style', 'Function ' + token.function.name + ' violates naming convention'))