Add subunit-tags to alter the tags on a test stream.

3 files changed, 128 insertions, 7 deletions

diff --git a/python/subunit/__init__.py b/python/subunit/__init__.py
index 84d9428..ff2ad66 100644
--- a/python/subunit/__init__.py
+++ b/python/subunit/__init__.py
@@ -43,6 +43,18 @@ def join_dir(base_path, path):
     return os.path.join(os.path.dirname(os.path.abspath(base_path)), path)
 
 
+def tags_to_new_gone(tags):
+    """Split a list of tags into a new_set and a gone_set."""
+    new_tags = set()
+    gone_tags = set()
+    for tag in tags:
+        if tag[0] == '-':
+            gone_tags.add(tag[1:])
+        else:
+            new_tags.add(tag)
+    return new_tags, gone_tags
+
+
 class TestProtocolServer(object):
     """A class for receiving results from a TestProtocol client.
     
@@ -173,13 +185,7 @@ class TestProtocolServer(object):
     def _handleTags(self, offset, line):
         """Process a tags command."""
         tags = line[offset:].split()
-        new_tags = set()
-        gone_tags = set()
-        for tag in tags:
-            if tag[0] == '-':
-                gone_tags.add(tag[1:])
-            else:
-                new_tags.add(tag)
+        new_tags, gone_tags = tags_to_new_gone(tags)
         if self.state == TestProtocolServer.OUTSIDE_TEST:
             update_tags = self.tags
         else:
@@ -568,3 +574,46 @@ def TAP2SubUnit(tap, subunit):
         # record missed tests
         plan_start = _skipped_test(subunit, plan_start)
     return 0
+
+
+def tag_stream(original, filtered, tags):
+    """Alter tags on a stream.
+
+    :param original: The input stream.
+    :param filtered: The output stream.
+    :param tags: The tags to apply. As in a normal stream - a list of 'TAG' or
+        '-TAG' commands.
+        A 'TAG' command will add the tag to the output stream,
+        and override any existing '-TAG' command in that stream.
+        Specifically:
+         * A global 'tags: TAG' will be added to the start of the stream.
+         * Any tags commands with -TAG will have the -TAG removed.
+        A '-TAG' command will remove the TAG command from the stream.
+        Specifically:
+         * A 'tags: -TAG' command will be added to the start of the stream.
+         * Any 'tags: TAG' command will have 'TAG' removed from it.
+        Additionally, any redundant tagging commands (adding a tag globally
+        present, or removing a tag globally removed) are stripped as a
+        by-product of the filtering.
+    :return: 0
+    """
+    new_tags, gone_tags = tags_to_new_gone(tags)
+    def write_tags(new_tags, gone_tags):
+        if new_tags or gone_tags:
+            filtered.write("tags: " + ' '.join(new_tags))
+            if gone_tags:
+                for tag in gone_tags:
+                    filtered.write("-" + tag)
+            filtered.write("\n")
+    write_tags(new_tags, gone_tags)
+    # TODO: use the protocol parser and thus don't mangle test comments.
+    for line in original:
+        if line.startswith("tags:"):
+            line_tags = line[5:].split()
+            line_new, line_gone = tags_to_new_gone(line_tags)
+            line_new = line_new - gone_tags
+            line_gone = line_gone - new_tags
+            write_tags(line_new, line_gone)
+        else:
+            filtered.write(line)
+    return 0
diff --git a/python/subunit/tests/__init__.py b/python/subunit/tests/__init__.py
index 7f501c7..6703514 100644
--- a/python/subunit/tests/__init__.py
+++ b/python/subunit/tests/__init__.py
@@ -19,6 +19,7 @@
 
 from subunit.tests import (
     TestUtil,
+    test_subunit_tags,
     test_tap2subunit,
     test_test_protocol,
     )
@@ -27,4 +28,5 @@ def test_suite():
     result = TestUtil.TestSuite()
     result.addTest(test_test_protocol.test_suite())
     result.addTest(test_tap2subunit.test_suite())
+    result.addTest(test_subunit_tags.test_suite())
     return result
diff --git a/python/subunit/tests/test_subunit_tags.py b/python/subunit/tests/test_subunit_tags.py
new file mode 100644
index 0000000..66cff68
--- /dev/null
+++ b/python/subunit/tests/test_subunit_tags.py
@@ -0,0 +1,70 @@
+#
+#  subunit: extensions to python unittest to get test results from subprocesses.
+#  Copyright (C) 2005  Robert Collins <robertc@robertcollins.net>
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software
+#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+
+"""Tests for subunit.tag_stream."""
+
+import unittest
+from StringIO import StringIO
+
+import subunit
+
+
+class TestSubUnitTags(unittest.TestCase):
+
+    def setUp(self):
+        self.original = StringIO()
+        self.filtered = StringIO()
+
+    def test_add_tag(self):
+        self.original.write("tags: foo\n")
+        self.original.write("test: test\n")
+        self.original.write("tags: bar -quux\n")
+        self.original.write("success: test\n")
+        self.original.seek(0)
+        result = subunit.tag_stream(self.original, self.filtered, ["quux"])
+        self.assertEqual([
+            "tags: quux",
+            "tags: foo",
+            "test: test",
+            "tags: bar",
+            "success: test",
+            ],
+            self.filtered.getvalue().splitlines())
+
+    def test_remove_tag(self):
+        self.original.write("tags: foo\n")
+        self.original.write("test: test\n")
+        self.original.write("tags: bar -quux\n")
+        self.original.write("success: test\n")
+        self.original.seek(0)
+        result = subunit.tag_stream(self.original, self.filtered, ["-bar"])
+        self.assertEqual([
+            "tags: -bar",
+            "tags: foo",
+            "test: test",
+            "tags: -quux",
+            "success: test",
+            ],
+            self.filtered.getvalue().splitlines())
+
+
+def test_suite():
+    loader = subunit.tests.TestUtil.TestLoader()
+    result = loader.loadTestsFromName(__name__)
+    return result