parser: Add support for rename-only patches

Yann E. MORIN reported a problem where patchwork drops patches with only
renames:

 http://lists.busybox.net/pipermail/buildroot/2013-October/079999.html

This change fixes the issue by adding a new state for patch 'meta'
headers: header test which is not parsed as a hunk, but has the same
behaviour as a hunk in that it will cause the patchbuf to be populated.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/apps/patchwork/parser.py b/apps/patchwork/parser.py
index f460566..8295980 100644
--- a/apps/patchwork/parser.py
+++ b/apps/patchwork/parser.py
@@ -45,6 +45,7 @@ def parse_patch(text):
     # 3: patch header line 2 (+++)
     # 4: patch hunk header line (@@ line)
     # 5: patch hunk content
+    # 6: patch meta header (rename from/rename to)
     #
     # valid transitions:
     #  0 -> 1 (diff, ===, Index:)
@@ -54,6 +55,9 @@ def parse_patch(text):
     #  3 -> 4 (@@ line)
     #  4 -> 5 (patch content)
     #  5 -> 1 (run out of lines from @@-specifed count)
+    #  1 -> 6 (rename from / rename to)
+    #  6 -> 2 (---)
+    #  6 -> 1 (other text)
     #
     # Suspected patch header is stored into buf, and appended to
     # patchbuf if we find a following hunk. Otherwise, append to
@@ -85,6 +89,9 @@ def parse_patch(text):
             if line.startswith('--- '):
                 state = 2
 
+            if line.startswith('rename from ') or line.startswith('rename to '):
+                state = 6
+
         elif state == 2:
             if line.startswith('+++ '):
                 state = 3
@@ -148,6 +155,20 @@ def parse_patch(text):
             else:
                 state = 5
 
+        elif state == 6:
+            if line.startswith('rename to ') or line.startswith('rename from '):
+                patchbuf += buf + line
+                buf = ''
+
+            elif line.startswith('--- '):
+                patchbuf += buf + line
+                buf = ''
+                state = 2
+
+            else:
+                buf += line
+                state = 1
+
         else:
             raise Exception("Unknown state %d! (line '%s')" % (state, line))