bpo-41207 In distutils.spawn, rewrite FileNotFound (GH-21359)

Automerge-Triggered-By: @jaraco

spawn.py

@@ -71,9 +71,15 @@ def spawn(cmd, search_path=1, verbose=0, dry_run=0):
  env = dict(os.environ,
  MACOSX_DEPLOYMENT_TARGET=cur_target)
 
- proc = subprocess.Popen(cmd, env=env)
- proc.wait()
- exitcode = proc.returncode
+ try:
+ proc = subprocess.Popen(cmd, env=env)
+ proc.wait()
+ exitcode = proc.returncode
+ except OSError as exc:
+ if not DEBUG:
+ cmd = cmd[0]
+ raise DistutilsExecError(
+ "command %r failed: %s" % (cmd, exc.args[-1])) from exc
 
  if exitcode:
  if not DEBUG:

tests/test_spawn.py

@@ -124,6 +124,11 @@ def test_find_executable(self):
  rv = find_executable(program)
  self.assertEqual(rv, filename)
 
+ def test_spawn_missing_exe(self):
+ with self.assertRaises(DistutilsExecError) as ctx:
+ spawn(['does-not-exist'])
+ self.assertIn("command 'does-not-exist' failed", str(ctx.exception))
+
 
 def test_suite():
  return unittest.makeSuite(SpawnTestCase)