Fall through unknown format to 'unified', fixed #18

cdiff.py

@@ -377,7 +377,7 @@ class UnifiedDiff(Diff):
 
     def is_hunk_meta(self, line):
         """Minimal valid hunk meta is like '@@ -1 +1 @@', note extra chars
-        might occur after the ending @@, e.g. in git log.  '## ' uaually
+        might occur after the ending @@, e.g. in git log.  '## ' usually
         indicates svn property changes in output from `svn log --diff`
         """
         return (line.startswith('@@ -') and line.find(' @@') >= 8) or \
@@ -484,6 +484,12 @@ class DiffParser(object):
                           header[3].startswith('*** ') and
                           header[3].rstrip().endswith(' ****')):
             self._type = 'context'
+
+            # For context diff, try use `filterdiff` to translate it to unified
+            # format and provide a new stream
+            #
+            # TODO
+
             return
 
         for n in range(size):
@@ -492,15 +498,11 @@ class DiffParser(object):
                 self._type = 'unified'
                 break
         else:
-            if size < 5:
-                # It's safe to consider as udiff if patch stream contains no
-                # more than 4 lines. happens with `git diff` on a file that
-                # only has perm bits changes or `svn diff` with property
-                # changes.
-                #
-                self._type = 'unified'
-            else:
-                raise RuntimeError('unknown diff type')
+            # `filterdiff` translate unknown diff to nothing, fall through to
+            # unified diff give cdiff a chance to show everything as headers
+            #
+            sys.stderr.write("*** unknown format, fall through to 'unified'\n")
+            self._type = 'unified'
 
     def get_diff_generator(self):
         """parse all diff lines, construct a list of Diff objects"""

tests/git-perm/in.diff

@@ -1,3 +1,6 @@
-diff --git a/CHANGES b/CHANGES
-old mode 100644
-new mode 100755
+diff --git a/cdiff b/cdiff
+old mode 100755
+new mode 100644
+diff --git a/cdiff.py b/cdiff.py
+old mode 100755
+new mode 100644

tests/git-perm/out.normal

@@ -1,4 +1,7 @@
-diff --git a/CHANGES b/CHANGES
-old mode 100644
-new mode 100755
+diff --git a/cdiff b/cdiff
+old mode 100755
+new mode 100644
+diff --git a/cdiff.py b/cdiff.py
+old mode 100755
+new mode 100644
 

tests/git-perm/out.side-by-side

@@ -1,4 +1,7 @@
-diff --git a/CHANGES b/CHANGES
-old mode 100644
-new mode 100755
+diff --git a/cdiff b/cdiff
+old mode 100755
+new mode 100644
+diff --git a/cdiff.py b/cdiff.py
+old mode 100755
+new mode 100644
 

tests/git-perm/out.w70

@@ -1,4 +1,7 @@
-diff --git a/CHANGES b/CHANGES
-old mode 100644
-new mode 100755
+diff --git a/cdiff b/cdiff
+old mode 100755
+new mode 100644
+diff --git a/cdiff.py b/cdiff.py
+old mode 100755
+new mode 100644
 

tests/regression.sh

@@ -33,7 +33,7 @@ function cmp_output()
     local cdiff_opt=${3:-""}
     local cmd
 
-    cmd=$(printf "%-8s $CDIFF %-18s < %-25s " $PYTHON "$cdiff_opt" "$input")
+    cmd=$(printf "%-8s $CDIFF %-18s <  %-30s " $PYTHON "$cdiff_opt" "$input")
     printf "$cmd"
     if eval $cmd 2>/dev/null | diff -ubq $expected_out - >& /dev/null; then
         pass

tests/test_cdiff.py

@@ -460,7 +460,8 @@ spam
 """
         items = patch.splitlines(True)
         stream = cdiff.PatchStream(Sequential(items))
-        self.assertRaises(RuntimeError, cdiff.DiffParser, stream)
+        parser = cdiff.DiffParser(stream)
+        self.assertEqual(parser._type, 'unified')
 
     def test_parse_invalid_hunk_meta(self):
         patch = """\