Make checking the existence of the license file optional in the license tool

tools/licenses.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Utility for checking and processing licensing information in third_party
 directories.
 
 Usage: licenses.py <command>
 
@@ skipping 216 matching lines @@
     if filename.startswith('/'):
         # Absolute-looking paths are relative to the source root
         # (which is the directory we're run from).
         absolute_path = os.path.join(os.getcwd(), filename[1:])
     else:
         absolute_path = os.path.join(path, filename)
     if os.path.exists(absolute_path):
         return absolute_path
     return None
 
-def ParseDir(path):
+def ParseDir(path, require_license_file=True):
     """Examine a third_party/foo component and extract its metadata."""
 
     # Parse metadata fields out of README.chromium.
     # We examine "LICENSE" for the license file by default.
     metadata = {
         "License File": "LICENSE",  # Relative path to license text.
         "Name": None,               # Short name (for header on about:credits).
         "URL": None,                # Project home page.
         "License": None,            # Software license.
         }
@@ skipping 27 matching lines @@
                                "in README.chromium or licences.py "
                                "SPECIAL_CASES")
 
     # Special-case modules that aren't in the shipping product, so don't need
     # their license in about:credits.
     if metadata["License File"] != NOT_SHIPPED:
         # Check that the license file exists.
         for filename in (metadata["License File"], "COPYING"):
             license_path = AbsolutePath(path, filename)
             if license_path is not None:
-                metadata["License File"] = license_path
                 break
 
-        if not license_path:
+        if require_license_file and not license_path:
             raise LicenseError("License file not found. "
                                "Either add a file named LICENSE, "
                                "import upstream's COPYING if available, "
                                "or add a 'License File:' line to "
                                "README.chromium with the appropriate path.")
+        metadata["License File"] = license_path
 
     if "Required Text" in metadata:
         required_path = AbsolutePath(path, metadata["Required Text"])
         if required_path is not None:
             metadata["Required Text"] = required_path
         else:
             raise LicenseError("Required text file listed but not found.")
 
     return metadata
 
@@ skipping 90 matching lines @@
             print >>sys.stderr, ("WARNING: licensing info for " + path +
                                  " is incomplete, skipping.")
             continue
         if metadata['License File'] == NOT_SHIPPED:
             print >>sys.stderr, ("Path " + path + " marked as " + NOT_SHIPPED +
                                  ", skipping.")
             continue
         env = {
             'name': metadata['Name'],
             'url': metadata['URL'],
             'license': open(metadata['License File'], 'rb').read(),

[Nico, 2012/08/16 18:10:15]

Won't this be confused about None license files?

[Steve Block, 2012/08/17 10:33:23]

No, because metadata comes from line 392, where we call ParseDir() with
require_license_file=True (the default). So if the license file is not found,
ParseDir() will raise an exception and we'll bail from the loop on line 396.

There should be no change in behaviour for either the 'scan' or 'credits'
command in this file.

             'license_unescaped': '',
         }
         if 'Required Text' in metadata:
             required_text = open(metadata['Required Text'], 'rb').read()
             env["license_unescaped"] = required_text
         entries.append(EvaluateTemplate(entry_template, env))
 
     file_template = open('chrome/browser/resources/about_credits.tmpl',
                          'rb').read()
     print "<!-- Generated by licenses.py; do not edit. -->"
@@ skipping 12 matching lines @@
     elif command == 'credits':
         if not GenerateCredits():
             return 1
     else:
         print __doc__
         return 1
 
 
 if __name__ == '__main__':
   sys.exit(main())