Possible diff regression in v1.7.6-473-g27af01d

Possible diff regression in v1.7.6-473-g27af01d

[Franz Schrober]

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Hi,

I am using git to manage some patches on top of the actual upstream files, but noticed that the result of git-format-patch changed between 4bfe7cb6668c43c1136304bbb17eea1b3ddf0237 and 27af01d552331eacf1ed2671b2b4b6ad4c268106

I've attached two input files (I tried to provide a minimal example... I am not sure if a smaller example is possible but at least both files are smaller than 10 lines) and the results with version 1.7.6.3 and and 1.7.7. The diffs were created using: git diff anonymized_orig anonymized_new

My .gitconfig file is empty.

Thanks

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0
0
0
0

[-- Attachment #3: anonymized_new --]
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1
2
0
3
4
5
6
7

[-- Attachment #4: diff.1.7.6.3 --]
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diff --git a/anonymized_orig b/anonymized_new
index 44e0be8..ad0f859 100644
--- a/anonymized_orig
+++ b/anonymized_new
@@ -1,4 +1,8 @@
-0
-0
-0
-0
+1
+2
+0
+3
+4
+5
+6
+7

[-- Attachment #5: diff.1.7.7 --]
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diff --git a/anonymized_orig b/anonymized_new
index 44e0be8..ad0f859 100644
--- a/anonymized_orig
+++ b/anonymized_new
@@ -1,4 +1,8 @@
+1
+2
 0
-0
-0
-0
+3
+4
+5
+6
+7

Re: Possible diff regression in v1.7.6-473-g27af01d

[Thomas Rast]

Franz Schrober wrote:
> Hi,
> 
> I am using git to manage some patches on top of the actual upstream files, but noticed that the result of git-format-patch changed between 4bfe7cb6668c43c1136304bbb17eea1b3ddf0237 and 27af01d552331eacf1ed2671b2b4b6ad4c268106
> 
> I've attached two input files (I tried to provide a minimal example... I am not sure if a smaller example is possible but at least both files are smaller than 10 lines) and the results with version 1.7.6.3 and and 1.7.7. The diffs were created using: git diff anonymized_orig anonymized_new
> 
> My .gitconfig file is empty.

I'm not sure why you call this a regression.  For the benefit of
people who hate saving attachments, you used

  $ paste anonymized_orig anonymized_new  | xclip
  0       1
  0       2
  0       0
  0       3
          4
          5
          6
          7

the old diff was

  --- a/anonymized_orig
  +++ b/anonymized_new
  @@ -1,4 +1,8 @@
  -0
  -0
  -0
  -0
  +1
  +2
  +0
  +3
  +4
  +5
  +6
  +7

and the new diff is

  --- a/anonymized_orig
  +++ b/anonymized_new
  @@ -1,4 +1,8 @@
  +1
  +2
   0
  -0
  -0
  -0
  +3
  +4
  +5
  +6
  +7
 
So the new diff correctly represents the change, and on top of that is
shorter (by only one line, admittedly).  What makes it a regression?

-- 
Thomas Rast
trast@{inf,student}.ethz.ch

Re: Possible diff regression in v1.7.6-473-g27af01d

[Tay Ray Chuan]

On Mon, Oct 24, 2011 at 5:38 PM, Thomas Rast <trast@student.ethz.ch> wrote:
>
> I'm not sure why you call this a regression.  For the benefit of
> people who hate saving attachments, you used
>
>  $ paste anonymized_orig anonymized_new  | xclip
>  0       1
>  0       2
>  0       0
>  0       3
>          4
>          5
>          6
>          7
>
> the old diff was
>
>  --- a/anonymized_orig
>  +++ b/anonymized_new
>  @@ -1,4 +1,8 @@
>  -0
>  -0
>  -0
>  -0
>  +1
>  +2
>  +0
>  +3
>  +4
>  +5
>  +6
>  +7
>
> and the new diff is
>
>  --- a/anonymized_orig
>  +++ b/anonymized_new
>  @@ -1,4 +1,8 @@
>  +1
>  +2
>   0
>  -0
>  -0
>  -0
>  +3
>  +4
>  +5
>  +6
>  +7
>
> So the new diff correctly represents the change, and on top of that is
> shorter (by only one line, admittedly).  What makes it a regression?

Thanks for inlining it, Thomas.

> Franz Schrober wrote:>> Hi,>>>> I am using git to manage some patches on top of the actual upstream files, but noticed that the result of git-format-patch changed between 4bfe7cb6668c43c1136304bbb17eea1b3ddf0237 and 27af01d552331eacf1ed2671b2b4b6ad4c268106>>>> I've attached two input files (I tried to provide a minimal example... I am not sure if a smaller example is possible but at least both files are smaller than 10 lines) and the results with version 1.7.6.3 and and 1.7.7. The diffs were created using: git diff anonymized_orig anonymized_new>>>> My .gitconfig file is empty.
This has been "fixed" in v1.7.7.1, with 713b85c (Merge branch
'rs/diff-cleanup-records-fix' into maint) - "fixed" in that it gives
back the old behaviour, not that the diff produced is incorrect and
needs fixing.
(I'm running 1.7.7.1.599.g03eec, I get the same diff as diff.1.7.6.3)

-- 
Cheers,
Ray Chuan