patman: Add a functional test

The existing test (patman --test) only covers basic checkpatch output.
We have had some problems with unicode processing and could use test
coverage for the various tags patman supports.

Add a new functional test which runs most of the patman flow on a few
test commits and checks that the results are correct.

See the documentation in the test for a description of what it does.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/tools/patman/patchstream.py b/tools/patman/patchstream.py
index 6098728..1b9136a 100644
--- a/tools/patman/patchstream.py
+++ b/tools/patman/patchstream.py
@@ -424,6 +424,19 @@
     """
     return GetMetaDataForList('HEAD~%d' % start, None, count)
 
+def GetMetaDataForTest(text):
+    """Process metadata from a file containing a git log. Used for tests
+
+    Args:
+        text:
+    """
+    series = Series()
+    ps = PatchStream(series, is_log=True)
+    for line in text.splitlines():
+        ps.ProcessLine(line)
+    ps.Finalize()
+    return series
+
 def FixPatch(backup_dir, fname, series, commit):
     """Fix up a patch file, by adding/removing as required.