Re: [PATCH v3] [GSOC] cherry-pick: use better advice message

[ZheNing Hu <adlternative@gmail.com>]

Junio C Hamano <gitster@pobox.com> 于2021年8月14日周六 上午4:14写道：
>
> Phillip Wood <phillip.wood123@gmail.com> writes:
>
> >> +++ b/t/t3507-cherry-pick-conflict.sh
> >> @@ -53,9 +53,12 @@ test_expect_success 'advice from failed cherry-pick' "
> >>      picked=\$(git rev-parse --short picked) &&
> >>      cat <<-EOF >expected &&
> >
> > If you quote the here doc end marker then there is no substitution in
> > the here doc so writing
> >
> >       cat <<-\EOF >expected &&
> >
> >>      error: could not apply \$picked... picked
> >> -    hint: after resolving the conflicts, mark the corrected paths
> >> -    hint: with 'git add <paths>' or 'git rm <paths>'
> >> -    hint: and commit the result with 'git commit'
> >> +    hint: Resolve all conflicts manually, mark them as resolved with
> >> +    hint: \"git add/rm <conflicted_files>\", then run
> >
> > means you can replace \" with " here
>
> Hmph, actually the double-quote that opens the body of
> test_expect_success should be stared at with a very cautious eyes,
> as they often do not mean what the author of the patch thought they
> do.  I can see that it already fooled your eyes into thinking that
> there is no substitution, but $picked needs to be substituted into
> its value.  The backslash before it is *not* about guarding it from
> substitution inside here-doc; it is to pass literal "$" into the
> string, which is the last parameter to test_expect_success, that
> gets eval'ed.
>

Yes, the escaping here comes from double-quote of test_expect_success
instead of here-doc.

> The original of this one, for example, would probably have been
> better if written like so:
>
> test_expect_success 'advice from failed cherry-pick' '
>         pristine_detach initial &&
>         SQ='\'' &&
>
>         picked=$(git rev-parse --short picked) &&
>         cat <<-EOF >expected &&
>         error: could not apply $picked... picked
>         hint: after resolving the conflicts, mark the corrected paths
>         hint: with ${SQ}git add <paths>${SQ} or ${SQ}git rm <paths>${SQ}
>         hint: and commit the result with ${SQ}git commit${SQ}
>         EOF
>         test_must_fail git cherry-pick picked 2>actual &&
>
>         test_cmp expected actual
> '
>

Um? This section is not working for me.

./test-lib.sh: eval: line 917: unexpected EOF while looking for matching `''
./test-lib.sh: eval: line 932: syntax error: unexpected end of file

> And because there is no single quote in the updated text, it would
> become:
>
> test_expect_success 'advice from failed cherry-pick' '
>         pristine_detach initial &&
>
>         picked=$(git rev-parse --short picked) &&
>         cat <<-EOF >expected &&
>         error: could not apply $picked... picked
>         hint: Resolve all conflicts manually, mark them as resolved with
>         hint: "git add/rm <conflicted_files>", then run
>         EOF
>         test_must_fail git cherry-pick picked 2>actual &&
>
>         test_cmp expected actual
> '
>
> which makes it far easier to see that $picked needs to be
> substituted, and the "git add/rm" are to be enclosed in dq pair.

This section is exactly what I want. Using single quotes does make it
look a lot easier.

--
ZheNing Hu