[PATCH] Remove --no-gui option from difftool usage string

[PATCH] Remove --no-gui option from difftool usage string

[Denton Liu]

The --no-gui option not documented in the manpage, nor is it actually
used in the source code. This change removes it from the usage help
that's printed.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
---
 git-difftool.perl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/git-difftool.perl b/git-difftool.perl
index a5790d03a..657d5622d 100755
--- a/git-difftool.perl
+++ b/git-difftool.perl
@@ -29,8 +29,8 @@ sub usage
 	print << 'USAGE';
 usage: git difftool [-t|--tool=<tool>] [--tool-help]
                     [-x|--extcmd=<cmd>]
-                    [-g|--gui] [--no-gui]
-                    [--prompt] [-y|--no-prompt]
+                    [-g|--gui] [--prompt]
+                    [-y|--no-prompt]
                     [-d|--dir-diff]
                     ['git diff' options]
 USAGE
-- 
2.11.0

Re: [PATCH] Remove --no-gui option from difftool usage string

[Jacob Keller]

On Fri, Feb 3, 2017 at 6:56 PM, Denton Liu <liu.denton@gmail.com> wrote:
> The --no-gui option not documented in the manpage, nor is it actually
> used in the source code. This change removes it from the usage help
> that's printed.
>
> Signed-off-by: Denton Liu <liu.denton@gmail.com>
> ---
>  git-difftool.perl | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/git-difftool.perl b/git-difftool.perl
> index a5790d03a..657d5622d 100755
> --- a/git-difftool.perl
> +++ b/git-difftool.perl
> @@ -29,8 +29,8 @@ sub usage
>         print << 'USAGE';
>  usage: git difftool [-t|--tool=<tool>] [--tool-help]
>                      [-x|--extcmd=<cmd>]
> -                    [-g|--gui] [--no-gui]
> -                    [--prompt] [-y|--no-prompt]
> +                    [-g|--gui] [--prompt]
> +                    [-y|--no-prompt]
>                      [-d|--dir-diff]
>                      ['git diff' options]
>  USAGE
> --
> 2.11.0
>

Aren't "--no-foo" options automatically created for booleans when
using our option parsing code?

Thanks,
Jake

Re: [PATCH] Remove --no-gui option from difftool usage string

[Denton Liu]

On Fri, Feb 03, 2017 at 09:58:09PM -0800, Jacob Keller wrote:
> On Fri, Feb 3, 2017 at 6:56 PM, Denton Liu <liu.denton@gmail.com> wrote:
> > The --no-gui option not documented in the manpage, nor is it actually
> > used in the source code. This change removes it from the usage help
> > that's printed.
> >
> > Signed-off-by: Denton Liu <liu.denton@gmail.com>
> > ---
> >  git-difftool.perl | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/git-difftool.perl b/git-difftool.perl
> > index a5790d03a..657d5622d 100755
> > --- a/git-difftool.perl
> > +++ b/git-difftool.perl
> > @@ -29,8 +29,8 @@ sub usage
> >         print << 'USAGE';
> >  usage: git difftool [-t|--tool=<tool>] [--tool-help]
> >                      [-x|--extcmd=<cmd>]
> > -                    [-g|--gui] [--no-gui]
> > -                    [--prompt] [-y|--no-prompt]
> > +                    [-g|--gui] [--prompt]
> > +                    [-y|--no-prompt]
> >                      [-d|--dir-diff]
> >                      ['git diff' options]
> >  USAGE
> > --
> > 2.11.0
> >
> 
> Aren't "--no-foo" options automatically created for booleans when
> using our option parsing code?
> 
> Thanks,
> Jake

Sorry, I guess I didn't notice that. Would it make sense to document it
in the manpage then?

--
Denton Liu

Re: [PATCH] Remove --no-gui option from difftool usage string

[David Aguilar]

On Fri, Feb 03, 2017 at 10:23:51PM -0800, Denton Liu wrote:
> On Fri, Feb 03, 2017 at 09:58:09PM -0800, Jacob Keller wrote:
> > On Fri, Feb 3, 2017 at 6:56 PM, Denton Liu <liu.denton@gmail.com> wrote:
> > > The --no-gui option not documented in the manpage, nor is it actually
> > > used in the source code. This change removes it from the usage help
> > > that's printed.
> > >
> > > Signed-off-by: Denton Liu <liu.denton@gmail.com>
> > > ---
> > >  git-difftool.perl | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/git-difftool.perl b/git-difftool.perl
> > > index a5790d03a..657d5622d 100755
> > > --- a/git-difftool.perl
> > > +++ b/git-difftool.perl
> > > @@ -29,8 +29,8 @@ sub usage
> > >         print << 'USAGE';
> > >  usage: git difftool [-t|--tool=<tool>] [--tool-help]
> > >                      [-x|--extcmd=<cmd>]
> > > -                    [-g|--gui] [--no-gui]
> > > -                    [--prompt] [-y|--no-prompt]
> > > +                    [-g|--gui] [--prompt]
> > > +                    [-y|--no-prompt]
> > >                      [-d|--dir-diff]
> > >                      ['git diff' options]
> > >  USAGE
> > > --
> > > 2.11.0
> > >
> > 
> > Aren't "--no-foo" options automatically created for booleans when
> > using our option parsing code?
> > 
> > Thanks,
> > Jake
> 
> Sorry, I guess I didn't notice that. Would it make sense to document it
> in the manpage then?

The general "--no-*" convention is mentioned in "git help cli",
but the manpages and usage strings across all commands are
inconsistent about mentioning the "--no-*" variants; some do,
some don't.

IMO it probably wouldn't hurt to document --no-gui in the manpage.

cheers,
-- 
David

[BUG] was: Re: [PATCH] Remove --no-gui option from difftool usage string

[David Aguilar]

On Fri, Feb 03, 2017 at 06:56:17PM -0800, Denton Liu wrote:
> The --no-gui option not documented in the manpage, nor is it actually
> used in the source code. This change removes it from the usage help
> that's printed.
> 
> Signed-off-by: Denton Liu <liu.denton@gmail.com>
> ---
>  git-difftool.perl | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

[Dscho, I found a bug, see below]

I forgot to mention that the scripted difftool has been
rewritten in C and will be going away soon.
builtin/difftool.c is already in "next".

New patches against difftool should target the builtin.

Regarding removing it from the usage string, IMO that can be
considered a good change if the rationale were instead that
we never expect users to ever type "--no-gui" in practice.

Wasting the short usage string screen space with a useless to
99.99% users option is bad for usability.  From that perspective
we shouldn't mention it there, so reframing the commit message
towards that argument would make for a better motivation.

Removing the mention from the usage string and adding it to the
manpage would be the a good change from that perspective as well.


BTW, in "next", it seems that the builtin difftool crashes when
doing "git difftool -h", so we should probably add a test
for that too...

From the tip of next:

$ git difftool -h
fatal: BUG: setup_git_env called without repository
-- 
David

[PATCH] difftool: fix bug when printing usage

[David Aguilar]

"git difftool -h" reports an error:

	fatal: BUG: setup_git_env called without repository

Defer repository setup so that the help option processing happens before
the repository is initialized.

Add tests to ensure that the basic usage works inside and outside of a
repository.

Signed-off-by: David Aguilar <davvid@gmail.com>
---
This bug exists in both "master" and "next".
This patch has been tested on both branches.

 builtin/difftool.c  |  8 ++++----
 t/t7800-difftool.sh | 13 +++++++++++++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/builtin/difftool.c b/builtin/difftool.c
index b5e85ab079..d13350ce83 100644
--- a/builtin/difftool.c
+++ b/builtin/difftool.c
@@ -647,10 +647,6 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 
-	/* NEEDSWORK: once we no longer spawn anything, remove this */
-	setenv(GIT_DIR_ENVIRONMENT, absolute_path(get_git_dir()), 1);
-	setenv(GIT_WORK_TREE_ENVIRONMENT, absolute_path(get_git_work_tree()), 1);
-
 	git_config(difftool_config, NULL);
 	symlinks = has_symlinks;
 
@@ -661,6 +657,10 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
 	if (tool_help)
 		return print_tool_help();
 
+	/* NEEDSWORK: once we no longer spawn anything, remove this */
+	setenv(GIT_DIR_ENVIRONMENT, absolute_path(get_git_dir()), 1);
+	setenv(GIT_WORK_TREE_ENVIRONMENT, absolute_path(get_git_work_tree()), 1);
+
 	if (use_gui_tool && diff_gui_tool && *diff_gui_tool)
 		setenv("GIT_DIFF_TOOL", diff_gui_tool, 1);
 	else if (difftool_cmd) {
diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index aa0ef02597..21e2ac4ad6 100755
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -23,6 +23,19 @@ prompt_given ()
 	test "$prompt" = "Launch 'test-tool' [Y/n]? branch"
 }
 
+test_expect_success 'basic usage requires no repo' '
+	lines=$(git difftool -h | grep ^usage: | wc -l) &&
+	test "$lines" -eq 1 &&
+	# create a ceiling directory to prevent Git from finding a repo
+	mkdir -p not/repo &&
+	ceiling="$PWD/not" &&
+	lines=$(cd not/repo &&
+		GIT_CEILING_DIRECTORIES="$ceiling" git difftool -h |
+		grep ^usage: | wc -l) &&
+	test "$lines" -eq 1 &&
+	rmdir -p not/repo
+'
+
 # Create a file on master and change it on branch
 test_expect_success 'setup' '
 	echo master >file &&
-- 
2.12.0.rc0.209.g3d1e53e462

Re: [PATCH] difftool: fix bug when printing usage

[Johannes Schindelin]

Hi David,

On Sun, 5 Feb 2017, David Aguilar wrote:

> "git difftool -h" reports an error:
> 
> 	fatal: BUG: setup_git_env called without repository
> 
> Defer repository setup so that the help option processing happens before
> the repository is initialized.
> 
> Add tests to ensure that the basic usage works inside and outside of a
> repository.
> 
> Signed-off-by: David Aguilar <davvid@gmail.com>
> ---
> This bug exists in both "master" and "next".
> This patch has been tested on both branches.

Thanks for noticing and for patching!

> diff --git a/builtin/difftool.c b/builtin/difftool.c
> index b5e85ab079..d13350ce83 100644
> --- a/builtin/difftool.c
> +++ b/builtin/difftool.c
> @@ -647,10 +647,6 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
>  		OPT_END()
>  	};
>  
> -	/* NEEDSWORK: once we no longer spawn anything, remove this */
> -	setenv(GIT_DIR_ENVIRONMENT, absolute_path(get_git_dir()), 1);
> -	setenv(GIT_WORK_TREE_ENVIRONMENT, absolute_path(get_git_work_tree()), 1);
> -
>  	git_config(difftool_config, NULL);
>  	symlinks = has_symlinks;
>  
> @@ -661,6 +657,10 @@ int cmd_difftool(int argc, const char **argv, const char *prefix)
>  	if (tool_help)
>  		return print_tool_help();
>  
> +	/* NEEDSWORK: once we no longer spawn anything, remove this */
> +	setenv(GIT_DIR_ENVIRONMENT, absolute_path(get_git_dir()), 1);
> +	setenv(GIT_WORK_TREE_ENVIRONMENT, absolute_path(get_git_work_tree()), 1);
> +
>  	if (use_gui_tool && diff_gui_tool && *diff_gui_tool)
>  		setenv("GIT_DIFF_TOOL", diff_gui_tool, 1);
>  	else if (difftool_cmd) {

Aaargh. You know, when you are used to code review systems where you can
easily increase the context of the diff hunks, static patches are...
tedious to review.

For the record: the context between those two hunks is:

       argc = parse_options(argc, argv, prefix, builtin_difftool_options,
                             builtin_difftool_usage, PARSE_OPT_KEEP_UNKNOWN |
                             PARSE_OPT_KEEP_DASHDASH);

> diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
> index aa0ef02597..21e2ac4ad6 100755
> --- a/t/t7800-difftool.sh
> +++ b/t/t7800-difftool.sh
> @@ -23,6 +23,19 @@ prompt_given ()
>  	test "$prompt" = "Launch 'test-tool' [Y/n]? branch"
>  }
>  
> +test_expect_success 'basic usage requires no repo' '
> +	lines=$(git difftool -h | grep ^usage: | wc -l) &&
> +	test "$lines" -eq 1 &&

It may be easier to debug future breakages if you wrote

	git difftool -h | grep ^usage: >output &&
	test_line_count = 1 output &&

or even better (changing the semantics now):

	test_expect_code 129 git difftool -h >output &&
	grep ^usage: output &&

> +	# create a ceiling directory to prevent Git from finding a repo
> +	mkdir -p not/repo &&
> +	ceiling="$PWD/not" &&
> +	lines=$(cd not/repo &&
> +		GIT_CEILING_DIRECTORIES="$ceiling" git difftool -h |
> +		grep ^usage: | wc -l) &&
> +	test "$lines" -eq 1 &&

Likewise, this would become

	GIT_CEILING_DIRECTORIES="$PWD/not" \
	test_expect_code 129 git -C not/repo difftool -h >output &&
	grep ^usage: output

> +	rmdir -p not/repo

I am not sure how portable `rmdir -p` is. Why not use

	test_when_finished rm -r not

instead?

But those are all really minor bike-sheddings, and I promised myself that
I would avoid those (as I find them rather pointless) unless there is at
least one real benefit. In this case, I think the result becomes more
readable:

-- snip --
diff --git a/t/t7800-difftool.sh b/t/t7800-difftool.sh
index 21e2ac4ad6d..7d7cb63d61e 100755
--- a/t/t7800-difftool.sh
+++ b/t/t7800-difftool.sh
@@ -24,16 +24,14 @@ prompt_given ()
 }
 
 test_expect_success 'basic usage requires no repo' '
-	lines=$(git difftool -h | grep ^usage: | wc -l) &&
-	test "$lines" -eq 1 &&
-	# create a ceiling directory to prevent Git from finding a repo
-	mkdir -p not/repo &&
-	ceiling="$PWD/not" &&
-	lines=$(cd not/repo &&
-		GIT_CEILING_DIRECTORIES="$ceiling" git difftool -h |
-		grep ^usage: | wc -l) &&
-	test "$lines" -eq 1 &&
-	rmdir -p not/repo
+	test_expect_code 129 git difftool -h >output &&
+	grep ^usage: output &&
+	# create a ceiling directory to prevent Git from finding a repo
+	mkdir -p not/repo &&
+	test_when_finished rm -r not &&
+	GIT_CEILING_DIRECTORIES="$PWD/not" \
+	test_expect_code 129 git -C not/repo difftool -h >output &&
+	grep ^usage: output
 '
 
 # Create a file on master and change it on branch
-- snap --

More importantly: When I read $PWD all kinds of alarm bells go off in my
head, as I immediately think of all the issues we have on Windows due to
Git's regression test using POSIX paths all over the place.

In this particular instance, it *does* work, magically, because the POSIX
path $PWD is automatically converted (by the MSYS2 runtime) into a Windows
path when git.exe is called.

Read: I actually tested this, in line with my resolution to avoid to
review merely patches (which would likely miss serious bugs) and instead
try to do full code reviews, including testing. That means that I will
review less, but better.

Insofar as I am the author of the builtin difftool:

Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Thanks,
Dscho

Re: [PATCH] difftool: fix bug when printing usage

[Junio C Hamano]

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

>> +test_expect_success 'basic usage requires no repo' '
>> +	lines=$(git difftool -h | grep ^usage: | wc -l) &&
>> +	test "$lines" -eq 1 &&
>
> It may be easier to debug future breakages if you wrote
>
> 	git difftool -h | grep ^usage: >output &&
> 	test_line_count = 1 output &&
> or even better (changing the semantics now):
>
> 	test_expect_code 129 git difftool -h >output &&
> 	grep ^usage: output &&

True.

>> +	# create a ceiling directory to prevent Git from finding a repo
>> +	mkdir -p not/repo &&
>> +	ceiling="$PWD/not" &&
>> +	lines=$(cd not/repo &&
>> +		GIT_CEILING_DIRECTORIES="$ceiling" git difftool -h |
>> +		grep ^usage: | wc -l) &&
>> +	test "$lines" -eq 1 &&
>
> Likewise, this would become
>
> 	GIT_CEILING_DIRECTORIES="$PWD/not" \
> 	test_expect_code 129 git -C not/repo difftool -h >output &&
> 	grep ^usage: output

I agree with the intent, but the execution here is "Not quite".
test_expect_code being a shell function, it does not take the
"one-shot environment assignment for this single invocation," like
external commands do.

> More importantly: When I read $PWD all kinds of alarm bells go off in my
> head, as I immediately think of all the issues we have on Windows due to
> Git's regression test using POSIX paths all over the place.

And we appreciate that somebody who is more familiar with the issue
is watching ;-).

> Insofar as I am the author of the builtin difftool:
>
> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>

OK, thanks.

Re: [PATCH] difftool: fix bug when printing usage

[Johannes Schindelin]

Hi Junio,

On Mon, 6 Feb 2017, Junio C Hamano wrote:

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> 
> > [... and he quoted someone ...]
> >
> >> +	# create a ceiling directory to prevent Git from finding a repo
> >> +	mkdir -p not/repo &&
> >> +	ceiling="$PWD/not" &&
> >> +	lines=$(cd not/repo &&
> >> +		GIT_CEILING_DIRECTORIES="$ceiling" git difftool -h |
> >> +		grep ^usage: | wc -l) &&
> >> +	test "$lines" -eq 1 &&
> >
> > Likewise, this would become
> >
> > 	GIT_CEILING_DIRECTORIES="$PWD/not" \
> > 	test_expect_code 129 git -C not/repo difftool -h >output &&
> > 	grep ^usage: output
> 
> I agree with the intent, but the execution here is "Not quite".
> test_expect_code being a shell function, it does not take the
> "one-shot environment assignment for this single invocation," like
> external commands do.

So now that we know what is wrong, can you please enlighten me about what
is right?

Thanks,
Johannes

Re: [PATCH] difftool: fix bug when printing usage

[Junio C Hamano]

Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

>> > Likewise, this would become
>> >
>> > 	GIT_CEILING_DIRECTORIES="$PWD/not" \
>> > 	test_expect_code 129 git -C not/repo difftool -h >output &&
>> > 	grep ^usage: output
>> 
>> I agree with the intent, but the execution here is "Not quite".
>> test_expect_code being a shell function, it does not take the
>> "one-shot environment assignment for this single invocation," like
>> external commands do.
>
> So now that we know what is wrong, can you please enlighten me about what
> is right?

David's original is just fine, isn't it?

Re: [PATCH] difftool: fix bug when printing usage

[Junio C Hamano]

Junio C Hamano <gitster@pobox.com> writes:

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
>>> > Likewise, this would become
>>> >
>>> > 	GIT_CEILING_DIRECTORIES="$PWD/not" \
>>> > 	test_expect_code 129 git -C not/repo difftool -h >output &&
>>> > 	grep ^usage: output
>>> 
>>> I agree with the intent, but the execution here is "Not quite".
>>> test_expect_code being a shell function, it does not take the
>>> "one-shot environment assignment for this single invocation," like
>>> external commands do.
>>
>> So now that we know what is wrong, can you please enlighten me about what
>> is right?
>
> David's original is just fine, isn't it?

I've also seen people use "env VAR=VAL git command" as the command
to be tested in t/ scripts.  You can run that under test_expect_code,
methinks.

Re: [PATCH] difftool: fix bug when printing usage

[Johannes Schindelin]

Hi Junio,

On Tue, 7 Feb 2017, Junio C Hamano wrote:

> Junio C Hamano <gitster@pobox.com> writes:
> 
> > Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> >
> >>> > Likewise, this would become
> >>> >
> >>> > 	GIT_CEILING_DIRECTORIES="$PWD/not" \
> >>> > 	test_expect_code 129 git -C not/repo difftool -h >output &&
> >>> > 	grep ^usage: output
> >>> 
> >>> I agree with the intent, but the execution here is "Not quite".
> >>> test_expect_code being a shell function, it does not take the
> >>> "one-shot environment assignment for this single invocation," like
> >>> external commands do.
> >>
> >> So now that we know what is wrong, can you please enlighten me about
> >> what is right?
> >
> > David's original is just fine, isn't it?
> 
> I've also seen people use "env VAR=VAL git command" as the command to be
> tested in t/ scripts.  You can run that under test_expect_code,
> methinks.

That is exactly what David ended up sending out as follow-up patches.

I did not mean to be critical, I just found it to be more helpful to
accompany "that does not work" comments with "but this does" in the past.

Ciao,
Johannes