Bug 1257326 - Add a parameter to restrict accepted origins for an option in python configure. r=glandium

MozReview-Commit-ID: 4Cme7fvl1fN

python/mozbuild/mozbuild/configure/help.py

@@ -16,6 +16,11 @@ class HelpFormatter(object):
 
     def add(self, option):
         assert isinstance(option, Option)
+
+        if option.possible_origins == ('implied',):
+            # Don't display help if our option can only be implied.
+            return
+
         # TODO: improve formatting
         target = self.options if option.name else self.env
         opt = option.option

python/mozbuild/mozbuild/configure/options.py

@@ -117,13 +117,16 @@ class Option(object):
       or '--without-', the implied default is a NegativeOptionValue.
     - `choices` restricts the set of values that can be given to the option.
     - `help` is the option description for use in the --help output.
+    - `possible_origins` is a tuple of strings that are origins accepted for
+      this option. Example origins are 'mozconfig', 'implied', and 'environment'.
     '''
     __slots__ = (
         'id', 'prefix', 'name', 'env', 'nargs', 'default', 'choices', 'help',
+        'possible_origins',
     )
 
     def __init__(self, name=None, env=None, nargs=None, default=None,
-                 choices=None, help=None):
+                 possible_origins=None, choices=None, help=None):
         if not name and not env:
             raise InvalidOptionError(
                 'At least an option name or an environment variable name must '
@@ -158,6 +161,10 @@ class Option(object):
                 'choices must be a tuple of strings')
         if not help:
             raise InvalidOptionError('A help string must be provided')
+        if possible_origins and not istupleofstrings(possible_origins):
+            raise InvalidOptionError(
+                'possible_origins must be a tuple of strings')
+        self.possible_origins = possible_origins
 
         if name:
             prefix, name, values = self.split_option(name)
@@ -300,6 +307,11 @@ class Option(object):
         if not option:
             return self.default
 
+        if self.possible_origins and origin not in self.possible_origins:
+            raise InvalidOptionError(
+                '%s can not be set by %s. Values are accepted from: %s' %
+                (option, origin, ', '.join(self.possible_origins)))
+
         prefix, name, values = self.split_option(option)
         option = self._join_option(prefix, name)
 

python/mozbuild/mozbuild/test/configure/test_options.py

@@ -785,6 +785,30 @@ class TestCommandLineHelper(unittest.TestCase):
         self.assertEqual('--with-foo=a,b', cm.exception.old_arg)
         self.assertEqual('command-line', cm.exception.old_origin)
 
+    def test_possible_origins(self):
+        with self.assertRaises(InvalidOptionError):
+            Option('--foo', possible_origins='command-line')
+
+        helper = CommandLineHelper({'BAZ': '1'}, ['cmd', '--foo', '--bar'])
+        foo = Option('--foo',
+                     possible_origins=('command-line',))
+        value, option = helper.handle(foo)
+        self.assertEquals(PositiveOptionValue(), value)
+        self.assertEquals('command-line', value.origin)
+        self.assertEquals('--foo', option)
+
+        bar = Option('--bar',
+                     possible_origins=('mozconfig',))
+        with self.assertRaisesRegexp(InvalidOptionError,
+            "--bar can not be set by command-line. Values are accepted from: mozconfig"):
+            helper.handle(bar)
+
+        baz = Option(env='BAZ',
+                     possible_origins=('implied',))
+        with self.assertRaisesRegexp(InvalidOptionError,
+            "BAZ=1 can not be set by environment. Values are accepted from: implied"):
+            helper.handle(baz)
+
 
 if __name__ == '__main__':
     main()