bug 1257607 - Add Version type to moz.configure. r=glandium

This change adds a `Version` type to moz.configure which is a small
wrapper around `distutils.version.Version`. It's suitable for wrapping
version numbers in configure checks and doing equality or greater-than
less-than comparisons in a sensible way.

MozReview-Commit-ID: BOL6yvemulG

--HG--
extra : rebase_source : 3b463eac0499086f8acffda0d01418b6ab17f3d6
extra : amend_source : aebd6e40c408d9f868623b2f53fcdf7455e2fff5

build/moz.configure/util.configure

@@ -89,6 +89,12 @@ def unique_list(l):
             result.append(i)
     return result
 
+@template
+@advanced
+def Version(v):
+    'A version number that can be compared usefully.'
+    from mozbuild.configure.util import Version as _Version
+    return _Version(v)
 
 # Denotes a deprecated option. Combines option() and @depends:
 # @deprecated_option('--option')

moz.configure

@@ -84,7 +84,7 @@ def perl_version_check(min_version):
     def get_perl_version(perl):
         import subprocess
         try:
-            return subprocess.check_output([perl, '-e', 'print $]'])
+            return Version(subprocess.check_output([perl, '-e', 'print $]']))
         except subprocess.CalledProcessError as e:
             error('Failed to get perl version: %s' % e.message)
 

python/moz.build

@@ -36,6 +36,7 @@ PYTHON_UNIT_TESTS += [
     'mozbuild/mozbuild/test/compilation/test_warnings.py',
     'mozbuild/mozbuild/test/configure/test_configure.py',
     'mozbuild/mozbuild/test/configure/test_options.py',
+    'mozbuild/mozbuild/test/configure/test_util.py',
     'mozbuild/mozbuild/test/controller/test_ccachestats.py',
     'mozbuild/mozbuild/test/controller/test_clobber.py',
     'mozbuild/mozbuild/test/frontend/test_context.py',

python/mozbuild/mozbuild/configure/util.py

@@ -0,0 +1,36 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import itertools
+from distutils.version import LooseVersion
+
+
+class Version(LooseVersion):
+    '''A simple subclass of distutils.version.LooseVersion.
+    Adds attributes for `major`, `minor`, `patch` for the first three
+    version components so users can easily pull out major/minor
+    versions, like:
+
+    v = Version('1.2b')
+    v.major == 1
+    v.minor == 2
+    v.patch == 0
+    '''
+    def __init__(self, version):
+        # Can't use super, LooseVersion's base class is not a new-style class.
+        LooseVersion.__init__(self, version)
+        # Take the first three integer components, stopping at the first
+        # non-integer and padding the rest with zeroes.
+        (self.major, self.minor, self.patch) = list(itertools.chain(
+            itertools.takewhile(lambda x:isinstance(x, int), self.version),
+            (0, 0, 0)))[:3]
+
+
+    def __cmp__(self, other):
+        # LooseVersion checks isinstance(StringType), so work around it.
+        if isinstance(other, unicode):
+            other = other.encode('ascii')
+        return LooseVersion.__cmp__(self, other)

python/mozbuild/mozbuild/test/configure/test_util.py

@@ -0,0 +1,49 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import unittest
+
+from mozunit import main
+
+from mozbuild.configure.util import Version
+
+
+class TestVersion(unittest.TestCase):
+    def test_version_simple(self):
+        v = Version('1')
+        self.assertEqual(v, '1')
+        self.assertLess(v, '2')
+        self.assertGreater(v, '0.5')
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 0)
+        self.assertEqual(v.patch, 0)
+
+    def test_version_more(self):
+        v = Version('1.2.3b')
+        self.assertLess(v, '2')
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 2)
+        self.assertEqual(v.patch, 3)
+
+    def test_version_bad(self):
+        # A version with a letter in the middle doesn't really make sense,
+        # so everything after it should be ignored.
+        v = Version('1.2b.3')
+        self.assertLess(v, '2')
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 2)
+        self.assertEqual(v.patch, 0)
+
+    def test_version_badder(self):
+        v = Version('1b.2.3')
+        self.assertLess(v, '2')
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 0)
+        self.assertEqual(v.patch, 0)
+
+
+if __name__ == '__main__':
+    main()