From 998d7741951c68b194eb9fab02509024bf60949e Mon Sep 17 00:00:00 2001
From: Claude Paroz <claude@2xlibre.net>
Date: Wed, 13 Jun 2018 21:37:46 +0200
Subject: [PATCH] Fixed #29492 -- Improved compilemessages speed

---
 .../management/commands/compilemessages.py    | 67 ++++++++++---------
 1 file changed, 37 insertions(+), 30 deletions(-)

diff --git a/django/core/management/commands/compilemessages.py b/django/core/management/commands/compilemessages.py
index 77dd0f085c..0934874662 100644
--- a/django/core/management/commands/compilemessages.py
+++ b/django/core/management/commands/compilemessages.py
@@ -1,4 +1,5 @@
 import codecs
+import concurrent.futures
 import glob
 import os
 
@@ -106,35 +107,41 @@ class Command(BaseCommand):
         """
         Locations is a list of tuples: [(directory, file), ...]
         """
-        for i, (dirpath, f) in enumerate(locations):
-            if self.verbosity > 0:
-                self.stdout.write('processing file %s in %s\n' % (f, dirpath))
-            po_path = os.path.join(dirpath, f)
-            if has_bom(po_path):
-                self.stderr.write(
-                    'The %s file has a BOM (Byte Order Mark). Django only '
-                    'supports .po files encoded in UTF-8 and without any BOM.' % po_path
-                )
-                self.has_errors = True
-                continue
-            base_path = os.path.splitext(po_path)[0]
+        with concurrent.futures.ThreadPoolExecutor() as executor:
+            futures = []
+            for i, (dirpath, f) in enumerate(locations):
+                if self.verbosity > 0:
+                    self.stdout.write('processing file %s in %s\n' % (f, dirpath))
+                po_path = os.path.join(dirpath, f)
+                if has_bom(po_path):
+                    self.stderr.write(
+                        'The %s file has a BOM (Byte Order Mark). Django only '
+                        'supports .po files encoded in UTF-8 and without any BOM.' % po_path
+                    )
+                    self.has_errors = True
+                    continue
+                base_path = os.path.splitext(po_path)[0]
 
-            # Check writability on first location
-            if i == 0 and not is_writable(base_path + '.mo'):
-                self.stderr.write(
-                    'The po files under %s are in a seemingly not writable location. '
-                    'mo files will not be updated/created.' % dirpath
-                )
-                self.has_errors = True
-                return
+                # Check writability on first location
+                if i == 0 and not is_writable(base_path + '.mo'):
+                    self.stderr.write(
+                        'The po files under %s are in a seemingly not writable location. '
+                        'mo files will not be updated/created.' % dirpath
+                    )
+                    self.has_errors = True
+                    return
 
-            args = [self.program] + self.program_options + [
-                '-o', base_path + '.mo', base_path + '.po'
-            ]
-            output, errors, status = popen_wrapper(args)
-            if status:
-                if errors:
-                    self.stderr.write('Execution of %s failed: %s.' % (self.program, errors))
-                else:
-                    self.stderr.write('Execution of %s failed.' % self.program)
-                self.has_errors = True
+                args = [self.program] + self.program_options + [
+                    '-o', base_path + '.mo', base_path + '.po'
+                ]
+                futures.append(executor.submit(popen_wrapper, args))
+
+            for future in concurrent.futures.as_completed(futures):
+                output, errors, status = future.result()
+                if status:
+                    if self.verbosity > 0:
+                        if errors:
+                            self.stderr.write("Execution of %s failed: %s" % (self.program, errors))
+                        else:
+                            self.stderr.write("Execution of %s failed" % self.program)
+                    self.has_errors = True