[BUG] git gui blame fails for multi-word textconv filter

> Hello,
>
> I use
>
>      [diff "astextplain"]
>          textconv = run-mailcap --action=cat
>
> in my ~/.gitconfig, and this works for git `git blame` because of 41a457
> in git.git (textconv: use shell to run helper), but fails with git gui:
>
>      $ git gui blame 21980.2--ИМС-МР231.doc
>      Error in startup script: couldn't execute "run-mailcap --action=cat": no such file or directory
>    

>          while executing
>      "open |[list $textconv $path] r"
>          (procedure "_load" line 56)
>          invoked from within
>      "_load $this $i_jump"
>          (procedure "blame::new" line 185)
>          invoked from within
>      "blame::new $head $path $jump_spec"
>          ("blame" arm line 6)
>          invoked from within
>      "switch -- $subcommand {
>              browser {
>                      if {$jump_spec ne {}} usage
>                      if {$head eq {}} {
>                              if {$path ne {}&&  [file isdirectory $path]} {
>                                      set head $..."
>          ("blame" arm line 57)
>          invoked from within
>      "switch -- $subcommand {
>      browser -
>      blame {
>              if {$subcommand eq "blame"} {
>                      set subcommand_args {[--line=<num>] rev? path}
>              } else {
>                      set subcommand_a..."
>          (file "/home/kirr/local/git/libexec/git-core/git-gui" line 2868)
>
>
>
> Thats is maybe because we use `git cat-file --textconv` only for in .git
> entries, but since cat-file lacks support for work-tree git-gui calls
> textconv filter itself manually on initial "$commit eq {}"?
>    

>diff --git a/git-gui/lib/blame.tcl b/git-gui/lib/blame.tcl
>index 2137ec9..77656d3 100644
>--- a/git-gui/lib/blame.tcl
>+++ b/git-gui/lib/blame.tcl
>@@ -460,7 +460,9 @@ method _load {jump} {
> 	}
> 	if {$commit eq {}} {
> 		if {$do_textconv ne 0} {
>-			set fd [open |[list $textconv $path] r]
>+			# Run textconv with sh -c "..." to allow it to
>+			# contain command + arguments.
>+			set fd [open |[list [shellpath] -c "$textconv \"\$0\"" $path] r]
> 		} else {
> 			set fd [open $path r]
> 		}

>> 	if {$commit eq {}} {
>> 		if {$do_textconv ne 0} {
>>-			set fd [open |[list $textconv $path] r]
>>+			# Run textconv with sh -c "..." to allow it to
>>+			# contain command + arguments.
>>+			set fd [open |[list [shellpath] -c "$textconv \"\$0\"" $path] r]
>> 		} else {
>> 			set fd [open $path r]
>> 		}
>
> I don't believe we need to put all this in to launch this via the
> shell. We just have to pass a list where the first element is the
> command-name.
>
> The following works for me using your 'textconv = odf2txt --width=40'
> test and also a 'textconv = od -t x1' that I tried for a hex dump
> output. I couldn't make run-mailcap do anything useful for me.
>
> diff --git a/lib/blame.tcl b/lib/blame.tcl
> index 2137ec9..c06ef04 100644
> --- a/lib/blame.tcl
> +++ b/lib/blame.tcl
> @@ -460,7 +460,7 @@ method _load {jump} {
>         }
>         if {$commit eq {}} {
>                 if {$do_textconv ne 0} {
> -                       set fd [open |[list $textconv $path] r]
> +                       set fd [open |[linsert $textconv end $path] r]
>                 } else {
>                         set fd [open $path r]
>                 }

>
>I'm not very fluent in Tcl, but I don't think this runs the command
>through a shell (pstree agrees with me). That will work in most cases,
>so that may be acceptable, but if you want to have full compatibility
>with what "git blame" does (by using a shell) and allow e.g.
>
>textconv = LANG=C some-command
>
>or
>
>textconv = cd ../; do-whatever
>
>which are already managed by "git blame" and are OK with my version,
>it's not going to do it.

>Le 04/08/2010 21:25, Kirill Smelkov a écrit :
>> Hello,
>>
>> I use
>>
>>      [diff "astextplain"]
>>          textconv = run-mailcap --action=cat
>>
>> in my ~/.gitconfig, and this works for git `git blame` because of 41a457
>> in git.git (textconv: use shell to run helper), but fails with git gui:
>>
>>      $ git gui blame 21980.2--ИМС-МР231.doc
>>      Error in startup script: couldn't execute "run-mailcap --action=cat": no such file or directory
>>    
>I wonder if spaces can be the reason of this. Looks like Tcl is
>looking for an executable called "run-mailcap --action=cat", and
>doesn't distinguish path from options.

> Le 04/08/2010 21:25, Kirill Smelkov a ??crit :
> >Hello,
> >
> >I use
> >
> >     [diff "astextplain"]
> >         textconv = run-mailcap --action=cat
> >
> >in my ~/.gitconfig, and this works for git `git blame` because of 41a457
> >in git.git (textconv: use shell to run helper), but fails with git gui:
> >
> >     $ git gui blame 21980.2--ИМС-МР231.doc
> >     Error in startup script: couldn't execute "run-mailcap --action=cat": 
> >     no such file or directory

> >If so, I'd better teach cat-file about worktree, instead of teaching
> >git-gui about running textconv filter through shell. Just a wish...
> >   
> This was discussed here: a1ace6b77167a2ad4b4995e8c4d09761@ensimag.fr , 
> and your suggestion was considered ;-)