Rev 2451: Ensure each HelpIndex has a unique prefix. in file:///home/robertc/source/baz/help-contexts/

[Robert Collins]

At file:///home/robertc/source/baz/help-contexts/

------------------------------------------------------------
revno: 2451
revision-id: robertc at robertcollins.net-20070420033220-bwu4sb8t1a6vfamw
parent: robertc at robertcollins.net-20070420031949-sxckxqm8tjtk9tzn
committer: Robert Collins <robertc at robertcollins.net>
branch nick: help-contexts
timestamp: Fri 2007-04-20 13:32:20 +1000
message:
  Ensure each HelpIndex has a unique prefix.
modified:
  bzrlib/errors.py               errors.py-20050309040759-20512168c4e14fbd
  bzrlib/help.py                 help.py-20050505025907-4dd7a6d63912f894
  bzrlib/tests/test_errors.py    test_errors.py-20060210110251-41aba2deddf936a8
  bzrlib/tests/test_help.py      test_help.py-20070419045354-6q6rq15j9e2n5fna-1
=== modified file 'bzrlib/errors.py'
--- a/bzrlib/errors.py	2007-04-20 00:14:15 +0000
+++ b/bzrlib/errors.py	2007-04-20 03:32:20 +0000
@@ -1540,6 +1540,14 @@
     _fmt = "Key %(key)s is already present in map"
 
 
+class DuplicateHelpPrefix(BzrError):
+
+    _fmt = "The prefix %(prefix)s is in the help search path twice."
+
+    def __init__(self, prefix):
+        self.prefix = prefix
+
+
 class MalformedTransform(BzrError):
 
     _fmt = "Tree transform is malformed %(conflicts)r"

=== modified file 'bzrlib/help.py'
--- a/bzrlib/help.py	2007-04-20 02:56:44 +0000
+++ b/bzrlib/help.py	2007-04-20 03:32:20 +0000
@@ -111,6 +111,15 @@
             _mod_commands.HelpCommandIndex(),
             ]
 
+    def _check_prefix_uniqueness(self):
+        """Ensure that the index collection is able to differentiate safely."""
+        prefixes = {}
+        for index in self.search_path:
+            prefixes.setdefault(index.prefix, []).append(index)
+        for prefix, indices in prefixes.items():
+            if len(indices) > 1:
+                raise errors.DuplicateHelpPrefix(prefix)
+
     def search(self, topic):
         """Search for topic across the help search path.
         
@@ -118,6 +127,7 @@
         :raises: NoHelpTopic if none of the indexs in search_path have topic.
         :return: A list of HelpTopics which matched 'topic'.
         """
+        self._check_prefix_uniqueness()
         result = []
         for index in self.search_path:
             result.extend(index.get_topics(topic))

=== modified file 'bzrlib/tests/test_errors.py'
--- a/bzrlib/tests/test_errors.py	2007-04-20 00:14:15 +0000
+++ b/bzrlib/tests/test_errors.py	2007-04-20 03:32:20 +0000
@@ -40,6 +40,11 @@
         self.assertEqualDiff('File id {a_file_id} already exists in inventory'
                              ' as foo', str(error))
 
+    def test_duplicate_help_prefix(self):
+        error = errors.DuplicateHelpPrefix('foo')
+        self.assertEqualDiff('The prefix foo is in the help search path twice.',
+            str(error))
+
     def test_inventory_modified(self):
         error = errors.InventoryModified("a tree to be repred")
         self.assertEqualDiff("The current inventory for the tree 'a tree to "

=== modified file 'bzrlib/tests/test_help.py'
--- a/bzrlib/tests/test_help.py	2007-04-20 03:19:49 +0000
+++ b/bzrlib/tests/test_help.py	2007-04-20 03:32:20 +0000
@@ -165,9 +165,9 @@
         calls = []
         class RecordingIndex(object):
             def __init__(self, name):
-                self.name = name
+                self.prefix = name
             def get_topics(self, topic):
-                calls.append(('get_topics', self.name, topic))
+                calls.append(('get_topics', self.prefix, topic))
                 return ['something']
         index = help.HelpIndices()
         index.search_path = [RecordingIndex('1'), RecordingIndex('2')]
@@ -190,10 +190,18 @@
     def test_search_returns_index_results(self):
         """Searching should return all the help topics found."""
         class CannedIndex(object):
-            def __init__(self, search_result):
+            def __init__(self, prefix, search_result):
+                self.prefix = prefix
                 self.result = search_result
             def get_topics(self, topic):
                 return self.result
         index = help.HelpIndices()
-        index.search_path = [CannedIndex(['a']), CannedIndex(['b', 'c'])]
+        index.search_path = [CannedIndex('1', ['a']), CannedIndex('2', ['b', 'c'])]
         self.assertEqual(['a', 'b', 'c'], index.search(None))
+
+    def test_search_checks_for_duplicate_prefixes(self):
+        """Its an error when there are multiple indices with the same prefix."""
+        indices = help.HelpIndices()
+        indices.search_path = [help_topics.HelpTopicIndex(),
+            help_topics.HelpTopicIndex()]
+        self.assertRaises(errors.DuplicateHelpPrefix, indices.search, None)