Allow CROS_WORKON_SRCROOT to be used outside the chroot.

bin/chromite

Index: bin/chromite
diff --git a/bin/chromite b/bin/chromite
index 4e9e49fc5d67046e5d93c09119cc2b9400a46422..dca06c87737d88241e2b9d6f5a879ca991d5332a 100755
--- a/bin/chromite
+++ b/bin/chromite
@@ -26,52 +26,52 @@ Since this script is _copied_, it should remain small and not use internal libs.
 import os
 import sys
 
-if __name__ == '__main__':
-  # Look relative to CROS_WORKON_SRCROOT if that variable exists.  This is
-  # the "inside the chroot" case.
-  if 'CROS_WORKON_SRCROOT' in os.environ:
-    chromite_path = os.path.join(os.environ['CROS_WORKON_SRCROOT'],
-                                 'chromite', 'shell', 'main.py')
-    if os.path.isfile(chromite_path):
-      # Exec the script, which will never return.
-      os.execv(chromite_path, sys.argv)
-    else:
-      print (
-          "ERROR: Couldn't find the chromite tool.\n"
-          "\n"
-          "You may need to update your chroot.  If you need help, see:\n"
-          "  http://www.chromium.org/chromium-os/developer-guide"
-      )
-      sys.exit(1)
 
-  # Outside the chroot, search upward until the "parent" dir doesn't change
-  # (on Linux, that means we're at '/').  That is an error case.
-  dir = os.getcwd()
-  prev_dir = None
-  while dir != prev_dir:
-    chromite_path = os.path.join(dir, 'chromite', 'shell', 'main.py')
-    if os.path.isfile(chromite_path):
-      # Add the directory above chromite to PYTHONPATH before executing, so
-      # that "import chromite.abc.xyz" works...
-      env = os.environ.copy()
+def ReportChromiteError(message):

[diandersAtChromium, 2011/02/01 23:08:16]

nit: Should probably start w/ _, since this is private.

+  print >>sys.stderr, (
+    "ERROR: Couldn't find the chromite tool.\n\n" + message +
+    "\n\nFor details and help, see:\n"
+    "  http://www.chromium.org/chromium-os/developer-guide"
+  )
+
+
+def TryChromiteShell(dir_, argv):

[diandersAtChromium, 2011/02/01 23:08:16]

nit: Also start w/ underscore.

+  chromite_path = os.path.join(dir_, 'chromite', 'shell', 'main.py')
+  if os.path.isfile(chromite_path):
+    env = os.environ.copy()
+    try:
+      import chromite
+    except:
       if 'PYTHONPATH' in env:
-        env['PYTHONPATH'] += ':%s' % dir
+        env['PYTHONPATH'] += ':%s' % dir_
       else:
-        env['PYTHONPATH'] = dir
+        env['PYTHONPATH'] = dir_
+    # Exec the script, which will never return.
+    os.execve(chromite_path, argv, env)
 
-      # Exec the script, which will never return.
-      os.execve(chromite_path, sys.argv, env)
 
-    prev_dir = dir
-    dir = os.path.dirname(dir)
+if __name__ == '__main__':
+  # Look relative to CROS_WORKON_SRCROOT if that variable exists.
+  # Inside the chroot, this variable should always be set; outside
+  # the setting is optional.
+  if 'CROS_WORKON_SRCROOT' in os.environ:
+    TryChromiteShell(os.environ['CROS_WORKON_SRCROOT'], sys.argv)
+    ReportChromiteError(
+      "There is no chromite package in the path indicated by\n"
+      "CROS_WORKON_SRCROOT.  The variable may be set wrong, or you\n"
+      "may need to update your chroot.")
+    sys.exit(1)
 
-  # TODO(dianders): Should we actually print out the 'repo init' call that
-  # the user should use?
-  print (
-      "ERROR: Couldn't find the chromite tool.\n"
-      "\n"
+  # We're outside the chroot and CROS_WORKON_SRCROOT isn't set.
+  # Search upward until the parent dir doesn't change (on Linux,
+  # that means we're at '/').
+  dir_ = os.getcwd()
+  prev_dir = None
+  while dir_ != prev_dir:
+    TryChromiteShell(dir_, sys.argv)
+    prev_dir = dir_
+    dir_ = os.path.dirname(dir_)
+  ReportChromiteError(
       "Please change to a directory inside your Chromium OS source tree\n"
-      "and retry.  If you need to setup a Chromium OS source tree, see:\n"
-      "  http://www.chromium.org/chromium-os/developer-guide"
-  )
+      "and retry.")
   sys.exit(1)