Process files in parallel.

1 files changed, 37 insertions, 5 deletions

diff --git a/isort/main.py b/isort/main.py
index eae7afa5..118ab693 100755
--- a/isort/main.py
+++ b/isort/main.py
@@ -24,6 +24,8 @@ import argparse
 import glob
 import os
 import sys
+from concurrent.futures import ProcessPoolExecutor
+import functools
 
 import setuptools
 
@@ -57,6 +59,21 @@ INTRO = r"""
 """.format(__version__)
 
 
+class SortAttempt(object):
+    def __init__(self, incorrectly_sorted, skipped):
+        self.incorrectly_sorted = incorrectly_sorted
+        self.skipped = skipped
+
+
+def sort_imports(file_name, **arguments):
+    try:
+        result = SortImports(file_name, **arguments)
+        return SortAttempt(result.incorrectly_sorted, result.skipped)
+    except IOError as e:
+        print("WARNING: Unable to parse file {0} due to {1}".format(file_name, e))
+        return None
+
+
 def iter_source_code(paths, config, skipped):
     """Iterate over all Python source files defined in paths."""
     for path in paths:
@@ -235,6 +252,8 @@ def create_parser():
     parser.add_argument('-lbt', '--lines-between-types', dest='lines_between_types', type=int)
     parser.add_argument('-up', '--use-parentheses', dest='use_parentheses', action='store_true',
                         help='Use parenthesis for line continuation on lenght limit instead of slashes.')
+    parser.add_argument('-j', '--jobs', help='Number of files to process in parallel.',
+                        dest='jobs', type=int)
 
     arguments = dict((key, value) for (key, value) in itemsview(vars(parser.parse_args())) if value)
     if 'dont_order_by_type' in arguments:
@@ -270,16 +289,29 @@ def main():
         num_skipped = 0
         if config['verbose'] or config.get('show_logo', False):
             print(INTRO)
-        for file_name in file_names:
-            try:
-                sort_attempt = SortImports(file_name, **arguments)
+        jobs = arguments.get('jobs')
+        if jobs:
+            executor = ProcessPoolExecutor(max_workers=jobs)
+
+            for sort_attempt in executor.map(functools.partial(sort_imports, **arguments), file_names):
+                if not sort_attempt:
+                    continue
                 incorrectly_sorted = sort_attempt.incorrectly_sorted
                 if arguments.get('check', False) and incorrectly_sorted:
                     wrong_sorted_files = True
                 if sort_attempt.skipped:
                     num_skipped += 1
-            except IOError as e:
-                print("WARNING: Unable to parse file {0} due to {1}".format(file_name, e))
+        else:
+            for file_name in file_names:
+                try:
+                    sort_attempt = SortImports(file_name, **arguments)
+                    incorrectly_sorted = sort_attempt.incorrectly_sorted
+                    if arguments.get('check', False) and incorrectly_sorted:
+                        wrong_sorted_files = True
+                    if sort_attempt.skipped:
+                        num_skipped += 1
+                except IOError as e:
+                    print("WARNING: Unable to parse file {0} due to {1}".format(file_name, e))
         if wrong_sorted_files:
             exit(1)