[2/2] git-gui: support for diff3 conflict style
diff mbox series

Message ID f1477ba53a03484a0440202065a5293c8795d3b7.1569443729.git.bert.wesarg@googlemail.com
State New
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Series
  • [1/2] git-gui: use existing interface to query a path's attribute
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Commit Message

Bert Wesarg Sept. 25, 2019, 8:38 p.m. UTC
This adds highlight support for the diff3 conflict style.

The common pre-image will be reversed to --, because it has been removed
and either replaced with ours or theirs side.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
---
 git-gui.sh   |  3 +++
 lib/diff.tcl | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+)

Comments

Pratyush Yadav Sept. 29, 2019, 3:04 p.m. UTC | #1
Hi Philip, Bert,

Is there any way I can test this change? Philip, I ran the rebase you 
mention in the GitHub issue [0], and I get that '9c8cba6862abe5ac821' is 
an unknown revision.

Is there any quick way I can reproduce this (maybe on a sample repo)?

[0] https://github.com/git-for-windows/git/issues/2340

On 25/09/19 10:38PM, Bert Wesarg wrote:
> This adds highlight support for the diff3 conflict style.
> 
> The common pre-image will be reversed to --, because it has been removed
> and either replaced with ours or theirs side.
> 
> Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
> ---
>  git-gui.sh   |  3 +++
>  lib/diff.tcl | 22 ++++++++++++++++++++++
>  2 files changed, 25 insertions(+)
> 
> diff --git a/git-gui.sh b/git-gui.sh
> index fd476b6..6d80f82 100755
> --- a/git-gui.sh
> +++ b/git-gui.sh
> @@ -3581,6 +3581,9 @@ $ui_diff tag conf d_s- \
>  $ui_diff tag conf d< \
>  	-foreground orange \
>  	-font font_diffbold
> +$ui_diff tag conf d| \
> +	-foreground orange \
> +	-font font_diffbold
>  $ui_diff tag conf d= \
>  	-foreground orange \
>  	-font font_diffbold
> diff --git a/lib/diff.tcl b/lib/diff.tcl
> index 0fd4600..6caf4e7 100644
> --- a/lib/diff.tcl
> +++ b/lib/diff.tcl
> @@ -347,6 +347,7 @@ proc start_show_diff {cont_info {add_opts {}}} {
>  	}
>  
>  	set ::current_diff_inheader 1
> +	set ::conflict_state {CONTEXT}
>  	fconfigure $fd \
>  		-blocking 0 \
>  		-encoding [get_path_encoding $path] \
> @@ -450,10 +451,28 @@ proc read_diff {fd conflict_size cont_info} {
>  			{++} {
>  				set regexp [string map [list %conflict_size $conflict_size]\
>  								{^\+\+([<>=]){%conflict_size}(?: |$)}]
> +				set regexp_pre_image [string map [list %conflict_size $conflict_size]\
> +								{^\+\+\|{%conflict_size}(?: |$)}]
>  				if {[regexp $regexp $line _g op]} {
>  					set is_conflict_diff 1
>  					set line [string replace $line 0 1 {  }]
> +					set markup {}
>  					set tags d$op
> +					switch -exact -- $op {
> +					< { set ::conflict_state {OURS} }
> +					= { set ::conflict_state {THEIRS} }
> +					> { set ::conflict_state {CONTEXT} }
> +					}
> +				} elseif {[regexp $regexp_pre_image $line]} {
> +					set is_conflict_diff 1
> +					set line [string replace $line 0 1 {  }]
> +					set markup {}
> +					set tags d|
> +					set ::conflict_state {BASE}
> +				} elseif {$::conflict_state eq {BASE}} {
> +					set line [string replace $line 0 1 {--}]
> +					set markup {}
> +					set tags d_--

I'm afraid I don't follow what this hunk is supposed to do.

You set the variable ::conflict_state to the values like OURS, THEIRS, 
CONTEXT, but I don't see those values being used anywhere. A quick 
search for these words shows me that you only set them, never read them.

Is there some extra code that you have and I don't?

Also, this function is long and complicated already. A comment 
explaining what this code is doing would be nice, since it is not at all 
obvious at first read-through.

>  				} else {
>  					set tags d_++
>  				}
> @@ -505,6 +524,9 @@ proc read_diff {fd conflict_size cont_info} {
>  			}
>  		}
>  		set mark [$ui_diff index "end - 1 line linestart"]
> +		if {[llength $markup] > 0} {
> +			set tags {}
> +		}
>  		$ui_diff insert end $line $tags
>  		if {[string index $line end] eq "\r"} {
>  			$ui_diff tag add d_cr {end - 2c}
> -- 
> 2.21.0.789.ga095d9d866
>
Bert Wesarg Sept. 30, 2019, 12:17 p.m. UTC | #2
Pratyush,

On Sun, Sep 29, 2019 at 5:04 PM Pratyush Yadav <me@yadavpratyush.com> wrote:
>
> Hi Philip, Bert,
>
> Is there any way I can test this change? Philip, I ran the rebase you
> mention in the GitHub issue [0], and I get that '9c8cba6862abe5ac821' is
> an unknown revision.
>
> Is there any quick way I can reproduce this (maybe on a sample repo)?

The easiest way to produce a merge conflict, is to change the same
line differently in two branches and try to merge them. I added a
fast-import file to demonstrate this for you.

$ git init foo
$ cd foo
$ git fast-import <../conflict-merge.fi
$ git reset --hard master
$ git merge branch

this gets you into the conflict, probably the usual style. Which looks
in liek this on the terminal:

@@@ -2,7 -2,7 +2,11 @@@ Lorem ipsum dolor sit amet, consectetu
  Sed feugiat nisl eget efficitur ultrices.
  Nunc cursus metus rutrum, mollis lorem vitae, hendrerit mi.
  Aenean vestibulum ante ac libero venenatis, non hendrerit orci pharetra.
++<<<<<<< HEAD
 +Proin bibendum purus ut est tristique, non pharetra dui consectetur.
++=======
+ Proin placerat leo malesuada lacinia lobortis.
++>>>>>>> branch
  Pellentesque aliquam libero et nisi scelerisque commodo.
  Quisque id velit sed magna molestie porttitor.
  Vivamus sed urna in risus molestie ultricies.

and this in git gui: https://kgab.selfhost.eu/s/gHHaQqowGp7mXEb

Git gui removes the '++' in front of the marker lines. It therefor
already 'changes' the 'diff'. Though git-apply cannot handle such
'diffs' anyway.

To get the diff3 style do:

$ git merge --abort
$ git -c merge.conflictStyle=diff3 merge branch

This is how it looks in the terminal now:

@@@ -2,7 -2,7 +2,13 @@@ Lorem ipsum dolor sit amet, consectetu
  Sed feugiat nisl eget efficitur ultrices.
  Nunc cursus metus rutrum, mollis lorem vitae, hendrerit mi.
  Aenean vestibulum ante ac libero venenatis, non hendrerit orci pharetra.
++<<<<<<< HEAD
 +Proin bibendum purus ut est tristique, non pharetra dui consectetur.
++||||||| merged common ancestors
++Proin in felis eu elit suscipit rhoncus vel ut metus.
++=======
+ Proin placerat leo malesuada lacinia lobortis.
++>>>>>>> branch
  Pellentesque aliquam libero et nisi scelerisque commodo.
  Quisque id velit sed magna molestie porttitor.
  Vivamus sed urna in risus molestie ultricies.

As you can see, there is not the usual 'I removed this, and added
that' experience, everything is 'added'. Thus I inverted the pre-image
to '--'. Here is how it looks in the gui:
https://kgab.selfhost.eu/s/5c8Tosra7WRfjwJ

> [0] https://github.com/git-for-windows/git/issues/2340
>
> On 25/09/19 10:38PM, Bert Wesarg wrote:
> > This adds highlight support for the diff3 conflict style.
> >
> > The common pre-image will be reversed to --, because it has been removed
> > and either replaced with ours or theirs side.
> >
> > Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
> > ---
> >  git-gui.sh   |  3 +++
> >  lib/diff.tcl | 22 ++++++++++++++++++++++
> >  2 files changed, 25 insertions(+)
> >
> > diff --git a/git-gui.sh b/git-gui.sh
> > index fd476b6..6d80f82 100755
> > --- a/git-gui.sh
> > +++ b/git-gui.sh
> > @@ -3581,6 +3581,9 @@ $ui_diff tag conf d_s- \
> >  $ui_diff tag conf d< \
> >       -foreground orange \
> >       -font font_diffbold
> > +$ui_diff tag conf d| \
> > +     -foreground orange \
> > +     -font font_diffbold
> >  $ui_diff tag conf d= \
> >       -foreground orange \
> >       -font font_diffbold
> > diff --git a/lib/diff.tcl b/lib/diff.tcl
> > index 0fd4600..6caf4e7 100644
> > --- a/lib/diff.tcl
> > +++ b/lib/diff.tcl
> > @@ -347,6 +347,7 @@ proc start_show_diff {cont_info {add_opts {}}} {
> >       }
> >
> >       set ::current_diff_inheader 1
> > +     set ::conflict_state {CONTEXT}
> >       fconfigure $fd \
> >               -blocking 0 \
> >               -encoding [get_path_encoding $path] \
> > @@ -450,10 +451,28 @@ proc read_diff {fd conflict_size cont_info} {
> >                       {++} {
> >                               set regexp [string map [list %conflict_size $conflict_size]\
> >                                                               {^\+\+([<>=]){%conflict_size}(?: |$)}]
> > +                             set regexp_pre_image [string map [list %conflict_size $conflict_size]\
> > +                                                             {^\+\+\|{%conflict_size}(?: |$)}]
> >                               if {[regexp $regexp $line _g op]} {
> >                                       set is_conflict_diff 1
> >                                       set line [string replace $line 0 1 {  }]
> > +                                     set markup {}
> >                                       set tags d$op
> > +                                     switch -exact -- $op {
> > +                                     < { set ::conflict_state {OURS} }
> > +                                     = { set ::conflict_state {THEIRS} }
> > +                                     > { set ::conflict_state {CONTEXT} }
> > +                                     }
> > +                             } elseif {[regexp $regexp_pre_image $line]} {
> > +                                     set is_conflict_diff 1
> > +                                     set line [string replace $line 0 1 {  }]
> > +                                     set markup {}
> > +                                     set tags d|
> > +                                     set ::conflict_state {BASE}
> > +                             } elseif {$::conflict_state eq {BASE}} {
> > +                                     set line [string replace $line 0 1 {--}]
> > +                                     set markup {}
> > +                                     set tags d_--
>
> I'm afraid I don't follow what this hunk is supposed to do.
>
> You set the variable ::conflict_state to the values like OURS, THEIRS,
> CONTEXT, but I don't see those values being used anywhere. A quick
> search for these words shows me that you only set them, never read them.

the last elseif depends on it.

I actually only need to detect the pre-image lines, which starts with
the ||| conflict-marker and ends with the === conflict-marker, instead
of all possible states.

>
> Is there some extra code that you have and I don't?
>
> Also, this function is long and complicated already. A comment
> explaining what this code is doing would be nice, since it is not at all
> obvious at first read-through.

Will re-send.

Bert

>
> >                               } else {
> >                                       set tags d_++
> >                               }
> > @@ -505,6 +524,9 @@ proc read_diff {fd conflict_size cont_info} {
> >                       }
> >               }
> >               set mark [$ui_diff index "end - 1 line linestart"]
> > +             if {[llength $markup] > 0} {
> > +                     set tags {}
> > +             }
> >               $ui_diff insert end $line $tags
> >               if {[string index $line end] eq "\r"} {
> >                       $ui_diff tag add d_cr {end - 2c}
> > --
> > 2.21.0.789.ga095d9d866
> >
>
> --
> Regards,
> Pratyush Yadav
Philip Oakley Oct. 3, 2019, 8:02 p.m. UTC | #3
On 30/09/2019 13:17, Bert Wesarg wrote:
> Pratyush,
>
> On Sun, Sep 29, 2019 at 5:04 PM Pratyush Yadav <me@yadavpratyush.com> wrote:
>> Hi Philip, Bert,
>>
>> Is there any way I can test this change? Philip, I ran the rebase you
>> mention in the GitHub issue [0], and I get that '9c8cba6862abe5ac821' is
>> an unknown revision.
>>
>> Is there any quick way I can reproduce this (maybe on a sample repo)?
> The easiest way to produce a merge conflict, is to change the same
> line differently in two branches and try to merge them. I added a
> fast-import file to demonstrate this for you.
>
> $ git init foo
> $ cd foo
> $ git fast-import <../conflict-merge.fi
> $ git reset --hard master
> $ git merge branch
>
> this gets you into the conflict, probably the usual style. Which looks
> in liek this on the terminal:
>
> @@@ -2,7 -2,7 +2,11 @@@ Lorem ipsum dolor sit amet, consectetu
>    Sed feugiat nisl eget efficitur ultrices.
>    Nunc cursus metus rutrum, mollis lorem vitae, hendrerit mi.
>    Aenean vestibulum ante ac libero venenatis, non hendrerit orci pharetra.
> ++<<<<<<< HEAD
>   +Proin bibendum purus ut est tristique, non pharetra dui consectetur.
> ++=======
> + Proin placerat leo malesuada lacinia lobortis.
> ++>>>>>>> branch
>    Pellentesque aliquam libero et nisi scelerisque commodo.
>    Quisque id velit sed magna molestie porttitor.
>    Vivamus sed urna in risus molestie ultricies.
>
> and this in git gui: https://kgab.selfhost.eu/s/gHHaQqowGp7mXEb

The snapshot of the Gui looks just the thing! (I've been away).

I'm sure this would solve my immediate issue.

My only remaining bikeshed question it prompted was to check which parts 
would be committed as part of committing the whole "hunk". But haven't 
had time to look at all!

>
> Git gui removes the '++' in front of the marker lines. It therefor
> already 'changes' the 'diff'. Though git-apply cannot handle such
> 'diffs' anyway.
>
> To get the diff3 style do:
>
> $ git merge --abort
> $ git -c merge.conflictStyle=diff3 merge branch
>
> This is how it looks in the terminal now:
>
> @@@ -2,7 -2,7 +2,13 @@@ Lorem ipsum dolor sit amet, consectetu
>    Sed feugiat nisl eget efficitur ultrices.
>    Nunc cursus metus rutrum, mollis lorem vitae, hendrerit mi.
>    Aenean vestibulum ante ac libero venenatis, non hendrerit orci pharetra.
> ++<<<<<<< HEAD
>   +Proin bibendum purus ut est tristique, non pharetra dui consectetur.
> ++||||||| merged common ancestors
> ++Proin in felis eu elit suscipit rhoncus vel ut metus.
> ++=======
> + Proin placerat leo malesuada lacinia lobortis.
> ++>>>>>>> branch
>    Pellentesque aliquam libero et nisi scelerisque commodo.
>    Quisque id velit sed magna molestie porttitor.
>    Vivamus sed urna in risus molestie ultricies.
>
> As you can see, there is not the usual 'I removed this, and added
> that' experience, everything is 'added'. Thus I inverted the pre-image
> to '--'. Here is how it looks in the gui:
> https://kgab.selfhost.eu/s/5c8Tosra7WRfjwJ
>
>> [0] https://github.com/git-for-windows/git/issues/2340
>>
>> On 25/09/19 10:38PM, Bert Wesarg wrote:
>>> This adds highlight support for the diff3 conflict style.
>>>
>>> The common pre-image will be reversed to --, because it has been removed
>>> and either replaced with ours or theirs side.
>>>
>>> Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
>>> ---
>>>   git-gui.sh   |  3 +++
>>>   lib/diff.tcl | 22 ++++++++++++++++++++++
>>>   2 files changed, 25 insertions(+)
>>>
>>> diff --git a/git-gui.sh b/git-gui.sh
>>> index fd476b6..6d80f82 100755
>>> --- a/git-gui.sh
>>> +++ b/git-gui.sh
>>> @@ -3581,6 +3581,9 @@ $ui_diff tag conf d_s- \
>>>   $ui_diff tag conf d< \
>>>        -foreground orange \
>>>        -font font_diffbold
>>> +$ui_diff tag conf d| \
>>> +     -foreground orange \
>>> +     -font font_diffbold
>>>   $ui_diff tag conf d= \
>>>        -foreground orange \
>>>        -font font_diffbold
>>> diff --git a/lib/diff.tcl b/lib/diff.tcl
>>> index 0fd4600..6caf4e7 100644
>>> --- a/lib/diff.tcl
>>> +++ b/lib/diff.tcl
>>> @@ -347,6 +347,7 @@ proc start_show_diff {cont_info {add_opts {}}} {
>>>        }
>>>
>>>        set ::current_diff_inheader 1
>>> +     set ::conflict_state {CONTEXT}
>>>        fconfigure $fd \
>>>                -blocking 0 \
>>>                -encoding [get_path_encoding $path] \
>>> @@ -450,10 +451,28 @@ proc read_diff {fd conflict_size cont_info} {
>>>                        {++} {
>>>                                set regexp [string map [list %conflict_size $conflict_size]\
>>>                                                                {^\+\+([<>=]){%conflict_size}(?: |$)}]
>>> +                             set regexp_pre_image [string map [list %conflict_size $conflict_size]\
>>> +                                                             {^\+\+\|{%conflict_size}(?: |$)}]
>>>                                if {[regexp $regexp $line _g op]} {
>>>                                        set is_conflict_diff 1
>>>                                        set line [string replace $line 0 1 {  }]
>>> +                                     set markup {}
>>>                                        set tags d$op
>>> +                                     switch -exact -- $op {
>>> +                                     < { set ::conflict_state {OURS} }
>>> +                                     = { set ::conflict_state {THEIRS} }
>>> +                                     > { set ::conflict_state {CONTEXT} }
>>> +                                     }
>>> +                             } elseif {[regexp $regexp_pre_image $line]} {
>>> +                                     set is_conflict_diff 1
>>> +                                     set line [string replace $line 0 1 {  }]
>>> +                                     set markup {}
>>> +                                     set tags d|
>>> +                                     set ::conflict_state {BASE}
>>> +                             } elseif {$::conflict_state eq {BASE}} {
>>> +                                     set line [string replace $line 0 1 {--}]
>>> +                                     set markup {}
>>> +                                     set tags d_--
>> I'm afraid I don't follow what this hunk is supposed to do.
>>
>> You set the variable ::conflict_state to the values like OURS, THEIRS,
>> CONTEXT, but I don't see those values being used anywhere. A quick
>> search for these words shows me that you only set them, never read them.
> the last elseif depends on it.
>
> I actually only need to detect the pre-image lines, which starts with
> the ||| conflict-marker and ends with the === conflict-marker, instead
> of all possible states.
>
>> Is there some extra code that you have and I don't?
>>
>> Also, this function is long and complicated already. A comment
>> explaining what this code is doing would be nice, since it is not at all
>> obvious at first read-through.
> Will re-send.
>
> Bert
>
>>>                                } else {
>>>                                        set tags d_++
>>>                                }
>>> @@ -505,6 +524,9 @@ proc read_diff {fd conflict_size cont_info} {
>>>                        }
>>>                }
>>>                set mark [$ui_diff index "end - 1 line linestart"]
>>> +             if {[llength $markup] > 0} {
>>> +                     set tags {}
>>> +             }
>>>                $ui_diff insert end $line $tags
>>>                if {[string index $line end] eq "\r"} {
>>>                        $ui_diff tag add d_cr {end - 2c}
>>> --
>>> 2.21.0.789.ga095d9d866
>>>
>> --
>> Regards,
>> Pratyush Yadav
Pratyush Yadav Oct. 3, 2019, 8:54 p.m. UTC | #4
On 03/10/19 09:02PM, Philip Oakley wrote:
> On 30/09/2019 13:17, Bert Wesarg wrote:
> > Pratyush,
> > 
> > On Sun, Sep 29, 2019 at 5:04 PM Pratyush Yadav <me@yadavpratyush.com> wrote:
> > > Hi Philip, Bert,
> > > 
> > > Is there any way I can test this change? Philip, I ran the rebase you
> > > mention in the GitHub issue [0], and I get that '9c8cba6862abe5ac821' is
> > > an unknown revision.
> > > 
> > > Is there any quick way I can reproduce this (maybe on a sample repo)?
> > The easiest way to produce a merge conflict, is to change the same
> > line differently in two branches and try to merge them. I added a
> > fast-import file to demonstrate this for you.
> > 
> > $ git init foo
> > $ cd foo
> > $ git fast-import <../conflict-merge.fi
> > $ git reset --hard master
> > $ git merge branch
> > 
> > this gets you into the conflict, probably the usual style. Which looks
> > in liek this on the terminal:
> > 
> > @@@ -2,7 -2,7 +2,11 @@@ Lorem ipsum dolor sit amet, consectetu
> >    Sed feugiat nisl eget efficitur ultrices.
> >    Nunc cursus metus rutrum, mollis lorem vitae, hendrerit mi.
> >    Aenean vestibulum ante ac libero venenatis, non hendrerit orci pharetra.
> > ++<<<<<<< HEAD
> >   +Proin bibendum purus ut est tristique, non pharetra dui consectetur.
> > ++=======
> > + Proin placerat leo malesuada lacinia lobortis.
> > ++>>>>>>> branch
> >    Pellentesque aliquam libero et nisi scelerisque commodo.
> >    Quisque id velit sed magna molestie porttitor.
> >    Vivamus sed urna in risus molestie ultricies.
> > 
> > and this in git gui: https://kgab.selfhost.eu/s/gHHaQqowGp7mXEb
> 
> The snapshot of the Gui looks just the thing! (I've been away).
> 
> I'm sure this would solve my immediate issue.
> 
> My only remaining bikeshed question it prompted was to check which parts
> would be committed as part of committing the whole "hunk". But haven't had
> time to look at all!

I'm not sure what you mean by "committing the whole hunk". In a merge 
conflict state, you don't get the usual "Stage hunk" and "Stage lines" 
options, but instead get 3 options:

  Use Remote Version
  Use Local Version
  Revert To Base

You can use these to choose how you want to resolve the conflict.

These 3 options seem to work fine on my quick testing.
Philip Oakley Oct. 3, 2019, 9:40 p.m. UTC | #5
On 03/10/2019 21:54, Pratyush Yadav wrote:
>> My only remaining bikeshed question it prompted was to check which parts
>> would be committed as part of committing the whole "hunk". But haven't had
>> time to look at all!
> I'm not sure what you mean by "committing the whole hunk". In a merge
> conflict state, you don't get the usual "Stage hunk" and "Stage lines"
> options, but instead get 3 options:
>
>    Use Remote Version
>    Use Local Version
>    Revert To Base
>
> You can use these to choose how you want to resolve the conflict.
>
> These 3 options seem to work fine on my quick testing.
That looks like just the answer I was hoping for!

Thanks.
Philip Oakley Oct. 4, 2019, 4:09 p.m. UTC | #6
On 04/10/2019 16:22, Bert Wesarg wrote:
> On Thu, Oct 3, 2019 at 11:40 PM Philip Oakley <philipoakley@iee.email> wrote:
>> On 03/10/2019 21:54, Pratyush Yadav wrote:
>>>> My only remaining bikeshed question it prompted was to check which parts
>>>> would be committed as part of committing the whole "hunk". But haven't had
>>>> time to look at all!
>>> I'm not sure what you mean by "committing the whole hunk". In a merge
>>> conflict state, you don't get the usual "Stage hunk" and "Stage lines"
>>> options, but instead get 3 options:
>>>
>>>     Use Remote Version
>>>     Use Local Version
>>>     Revert To Base
>>>
>>> You can use these to choose how you want to resolve the conflict.
>>>
>>> These 3 options seem to work fine on my quick testing.
>> That looks like just the answer I was hoping for!
> note, that these three options apply to the whole file, not for
> individual conflicts.
>
>
Hmm, maybe not as great as hoped, but it's a start.
Philip

Patch
diff mbox series

diff --git a/git-gui.sh b/git-gui.sh
index fd476b6..6d80f82 100755
--- a/git-gui.sh
+++ b/git-gui.sh
@@ -3581,6 +3581,9 @@  $ui_diff tag conf d_s- \
 $ui_diff tag conf d< \
 	-foreground orange \
 	-font font_diffbold
+$ui_diff tag conf d| \
+	-foreground orange \
+	-font font_diffbold
 $ui_diff tag conf d= \
 	-foreground orange \
 	-font font_diffbold
diff --git a/lib/diff.tcl b/lib/diff.tcl
index 0fd4600..6caf4e7 100644
--- a/lib/diff.tcl
+++ b/lib/diff.tcl
@@ -347,6 +347,7 @@  proc start_show_diff {cont_info {add_opts {}}} {
 	}
 
 	set ::current_diff_inheader 1
+	set ::conflict_state {CONTEXT}
 	fconfigure $fd \
 		-blocking 0 \
 		-encoding [get_path_encoding $path] \
@@ -450,10 +451,28 @@  proc read_diff {fd conflict_size cont_info} {
 			{++} {
 				set regexp [string map [list %conflict_size $conflict_size]\
 								{^\+\+([<>=]){%conflict_size}(?: |$)}]
+				set regexp_pre_image [string map [list %conflict_size $conflict_size]\
+								{^\+\+\|{%conflict_size}(?: |$)}]
 				if {[regexp $regexp $line _g op]} {
 					set is_conflict_diff 1
 					set line [string replace $line 0 1 {  }]
+					set markup {}
 					set tags d$op
+					switch -exact -- $op {
+					< { set ::conflict_state {OURS} }
+					= { set ::conflict_state {THEIRS} }
+					> { set ::conflict_state {CONTEXT} }
+					}
+				} elseif {[regexp $regexp_pre_image $line]} {
+					set is_conflict_diff 1
+					set line [string replace $line 0 1 {  }]
+					set markup {}
+					set tags d|
+					set ::conflict_state {BASE}
+				} elseif {$::conflict_state eq {BASE}} {
+					set line [string replace $line 0 1 {--}]
+					set markup {}
+					set tags d_--
 				} else {
 					set tags d_++
 				}
@@ -505,6 +524,9 @@  proc read_diff {fd conflict_size cont_info} {
 			}
 		}
 		set mark [$ui_diff index "end - 1 line linestart"]
+		if {[llength $markup] > 0} {
+			set tags {}
+		}
 		$ui_diff insert end $line $tags
 		if {[string index $line end] eq "\r"} {
 			$ui_diff tag add d_cr {end - 2c}