feat(mi): add --sort option

Fixes #100

radon/cli/__init__.py

@@ -92,7 +92,7 @@ def raw(paths, exclude=None, ignore=None, summary=False, json=False):
 @program.command
 @program.arg('paths', nargs='+')
 def mi(paths, min='A', max='C', multi=True, exclude=None, ignore=None,
-       show=False, json=False):
+       show=False, json=False, sort=False):
     '''Analyze the given Python modules and compute the Maintainability Index.
 
     The maintainability index (MI) is a compound metric, with the primary aim
@@ -112,6 +112,7 @@ def mi(paths, min='A', max='C', multi=True, exclude=None, ignore=None,
         comments.
     :param -s, --show: If given, the actual MI value is shown in results.
     :param -j, --json: Format results in JSON.
+    :param --sort: If given, results are sorted in ascending order.
     '''
     config = Config(
         min=min.upper(),
@@ -120,6 +121,7 @@ def mi(paths, min='A', max='C', multi=True, exclude=None, ignore=None,
         ignore=ignore,
         multi=multi,
         show=show,
+        sort=sort,
     )
 
     harvester = MIHarvester(paths, config)

radon/cli/harvest.py

@@ -250,9 +250,14 @@ def filtered_results(self):
         '''Filter results with respect with their rank.'''
         for key, value in self.results:
             if ('error' in value or
-               self.config.min <= value['rank'] <= self.config.max):
+                    self.config.min <= value['rank'] <= self.config.max):
                 yield (key, value)
 
+    def _sort(self, results):
+        if self.config.sort:
+            return sorted(results, key=lambda el: el[1]['mi'])
+        return results
+
     def as_json(self):
         '''Format the results as JSON.'''
         return json.dumps(dict(self.filtered_results))
@@ -263,7 +268,7 @@ def as_xml(self):
 
     def to_terminal(self):
         '''Yield lines to be printed to a terminal.'''
-        for name, mi in self.filtered_results:
+        for name, mi in self._sort(self.filtered_results):
             if 'error' in mi:
                 yield name, (mi['error'],), {'error': True}
                 continue