If managed=False, don't fetch.

This is an issue when bot_update.py is used, and a top-level
solution takes a long time to fetch.  Without this change, it will
be fetched twice.

managed=False really means 'hands off my checkout', so gclient
should honor that.

R=hinoka@chromium.org,agable@chromium.org
BUG=

Review URL: https://codereview.chromium.org/334343002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@277565 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/gclient_scm.py b/gclient_scm.py
index 26d9658..1b50abe 100644
--- a/gclient_scm.py
+++ b/gclient_scm.py
@@ -356,6 +356,13 @@
       verbose = ['--verbose']
       printed_path = True
 
+    if not managed:
+      self.Print('________ unmanaged solution; skipping %s' % self.relpath)
+      try:
+        return self._Capture(['rev-parse', '--verify', 'HEAD'])
+      except subprocess2.CalledProcessError:
+        return None
+
     url = self._CreateOrUpdateCache(url, options)
 
     if revision.startswith('refs/'):
@@ -389,11 +396,6 @@
         self.Print('')
       return self._Capture(['rev-parse', '--verify', 'HEAD'])
 
-    if not managed:
-      self._UpdateBranchHeads(options, fetch=False)
-      self.Print('________ unmanaged solution; skipping %s' % self.relpath)
-      return self._Capture(['rev-parse', '--verify', 'HEAD'])
-
     # See if the url has changed (the unittests use git://foo for the url, let
     # that through).
     current_url = self._Capture(['config', 'remote.%s.url' % self.remote])
diff --git a/tests/gclient_scm_test.py b/tests/gclient_scm_test.py
index 0341229..f2d35ea 100755
--- a/tests/gclient_scm_test.py
+++ b/tests/gclient_scm_test.py
@@ -1413,19 +1413,17 @@
                                 root_dir=self.root_dir,
                                 relpath=self.relpath)
 
-    expected_file_list = [join(self.base_path, "a"),
-                          join(self.base_path, "b")]
     file_list = []
     options.revision = 'unmanaged'
     scm.update(options, (), file_list)
 
-    self.assertEquals(file_list, expected_file_list)
-    self.assertEquals(scm.revinfo(options, (), None),
-                      '069c602044c5388d2d15c3f875b057c852003458')
+    self.assertEquals(file_list, [])
+    self.assertRaises(subprocess2.CalledProcessError,
+                      scm.revinfo, options, (), None)
+
     # indicates detached HEAD
-    self.assertEquals(self.getCurrentBranch(), None)
-    self.checkInStdout(
-      'Checked out refs/remotes/origin/master to a detached HEAD')
+    self.assertRaises(subprocess2.CalledProcessError, self.getCurrentBranch)
+    self.checkInStdout('unmanaged solution; skipping')
 
     rmtree(origin_root_dir)
 
@@ -1445,19 +1443,16 @@
                                 root_dir=self.root_dir,
                                 relpath=self.relpath)
 
-    expected_file_list = [join(self.base_path, "a"),
-                          join(self.base_path, "b")]
     file_list = []
     options.revision = 'unmanaged'
     scm.update(options, (), file_list)
 
-    self.assertEquals(file_list, expected_file_list)
-    self.assertEquals(scm.revinfo(options, (), None),
-                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
+    self.assertEquals(file_list, [])
+    self.assertRaises(subprocess2.CalledProcessError,
+                      scm.revinfo, options, (), None)
     # indicates detached HEAD
-    self.assertEquals(self.getCurrentBranch(), None)
-    self.checkInStdout(
-      'Checked out a7142dc9f0009350b96a11f372b6ea658592aa95 to a detached HEAD')
+    self.assertRaises(subprocess2.CalledProcessError, self.getCurrentBranch)
+    self.checkInStdout('unmanaged solution; skipping')
 
     rmtree(origin_root_dir)
 
@@ -1476,17 +1471,14 @@
                                 root_dir=self.root_dir,
                                 relpath=self.relpath)
 
-    expected_file_list = [join(self.base_path, "a"),
-                          join(self.base_path, "b"),
-                          join(self.base_path, "c")]
     file_list = []
     options.revision = 'unmanaged'
     scm.update(options, (), file_list)
 
-    self.assertEquals(file_list, expected_file_list)
-    self.assertEquals(scm.revinfo(options, (), None),
-                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
-    self.assertEquals(self.getCurrentBranch(), 'feature')
+    self.assertEquals(file_list, [])
+    self.assertRaises(subprocess2.CalledProcessError,
+                      scm.revinfo, options, (), None)
+    self.assertRaises(subprocess2.CalledProcessError, self.getCurrentBranch)
     self.checkNotInStdout('Checked out feature to a detached HEAD')
 
     rmtree(origin_root_dir)
@@ -1506,20 +1498,16 @@
                                 root_dir=self.root_dir,
                                 relpath=self.relpath)
 
-    expected_file_list = [join(self.base_path, "a"),
-                          join(self.base_path, "b"),
-                          join(self.base_path, "c")]
     file_list = []
     options.revision = 'unmanaged'
-    scm.update(options, (), file_list)
+    scm.update(options, (), [])
 
-    self.assertEquals(file_list, expected_file_list)
-    self.assertEquals(scm.revinfo(options, (), None),
-                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
+    self.assertEquals(file_list, [])
+    self.assertRaises(subprocess2.CalledProcessError,
+                      scm.revinfo, options, (), None)
     # indicates detached HEAD
-    self.assertEquals(self.getCurrentBranch(), None)
-    self.checkInStdout(
-      'Checked out refs/remotes/origin/feature to a detached HEAD')
+    self.assertRaises(subprocess2.CalledProcessError, self.getCurrentBranch)
+    self.checkInStdout('unmanaged solution; skipping')
 
     rmtree(origin_root_dir)
 
@@ -1538,17 +1526,14 @@
                                 root_dir=self.root_dir,
                                 relpath=self.relpath)
 
-    expected_file_list = [join(self.base_path, "a"),
-                          join(self.base_path, "b"),
-                          join(self.base_path, "c")]
     file_list = []
     options.revision = 'unmanaged'
     scm.update(options, (), file_list)
 
-    self.assertEquals(file_list, expected_file_list)
-    self.assertEquals(scm.revinfo(options, (), None),
-                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
-    self.assertEquals(self.getCurrentBranch(), 'feature')
+    self.assertEquals(file_list, [])
+    self.assertRaises(subprocess2.CalledProcessError,
+                      scm.revinfo, options, (), None)
+    self.assertRaises(subprocess2.CalledProcessError, self.getCurrentBranch)
     self.checkNotInStdout(
       'Checked out refs/heads/feature to a detached HEAD')