bug#15303: 24.3; [diff-mode] diff-hunk-kill doesn't update numbers in subsequent hunks

[Matěj Cepl]

1) Start Emacs
2) Open a patch file, it will open in a diff-mode
3) kill a hunk (Alt-K)

Example:

Let's have a patch with two subsequent hunks:

 curves = [
@@ -108,6 +117,9 @@ Hunk #2, a/tests/test_ec_curves.py curves = [
 #    ('ipsec4', 185),
 #]
 
+
+@unittest.skipUnless(EC_Module_Available,
+                     'Requires EC modules compiled into OpenSSL')
 class ECCurveTests(unittest.TestCase):
     #data = sha.sha('Kilroy was here!').digest()     # 160 bits
     data = "digest"     # keep short (48 bits) so lesser curves 
@@ -153,7 +165,8 @@ Hunk #3, a/tests/test_ec_curves.py def suite():
 
[end of example] 

When I am on line with @unittest.skipUnless and press Alt-K the result
is:

 curves = [
@@ -153,7 +165,8 @@ Hunk #3, a/tests/test_ec_curves.py def suite():

[end of example] 

That's actually wrong. The original hunk added three lines to the new
file, so when it is killed, the new line number in the hunk header
should be decreased by three, so the line should be

@@ -153,7 +162,8 @@

Best,

Matěj Cepl


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