Re: [PATCH v3 3/3] t2400: rewrite regex to avoid unintentional PCRE
From: Junio C Hamano <hidden>
Date: 2023-07-21 15:16:47
Jacob Abel [off-list ref] writes:
Replace all cases of `\s` with ` ` as it is not part of POSIX BRE or ERE and therefore not all versions of grep handle it without PCRE support.
Good point. But the patch replaces them with "[ ]" instead, which probably is not a good idea for readability. Technically speaking, there is no regular expression library that supports PCRE per-se; treating \S, \s, \d and the like the same way as PCRE is a GNU extension in the glibc land, and a simlar "enhanced mode" can be requested by passing REG_ENHANCED bit to regcomp(3) at runtime in the BSD land including macOS. I would suggest just dropping "without PCRE support" for brevity, as "not all versions of grep handle it" is sufficient here.
For the same reason all cases of `\S` are replaced with `[^ ]`. It's not an exact replacement but it is close enough for this use case.
Good.
quoted hunk
Signed-off-by: Jacob Abel <redacted> --- t/t2400-worktree-add.sh | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)diff --git a/t/t2400-worktree-add.sh b/t/t2400-worktree-add.sh index e106540c6d..eafecdf7ce 100755 --- a/t/t2400-worktree-add.sh +++ b/t/t2400-worktree-add.sh@@ -417,9 +417,9 @@ test_wt_add_orphan_hint () { grep "hint: If you meant to create a worktree containing a new orphan branch" actual && if [ $use_branch -eq 1 ] then - grep -E "^hint:\s+git worktree add --orphan -b \S+ \S+\s*$" actual + grep -E "^hint:[ ]+git worktree add --orphan -b [^ ]+ [^ ]+$" actual else - grep -E "^hint:\s+git worktree add --orphan \S+\s*$" actual + grep -E "^hint:[ ]+git worktree add --orphan [^ ]+$" actual fi
Just a single space would be fine without [bracket]. I think older tests use (literally) HT and SP inside [], many of them may still survive.
quoted hunk
@@ -709,7 +709,7 @@ test_dwim_orphan () { local info_text="No possible source branch, inferring '--orphan'" && local fetch_error_text="fatal: No local or remote refs exist despite at least one remote" && local orphan_hint="hint: If you meant to create a worktree containing a new orphan branch" && - local invalid_ref_regex="^fatal: invalid reference:\s\+.*" && + local invalid_ref_regex="^fatal: invalid reference: .*" &&
Feeding "<something>\+" to BRE (this pattern is later used with 'grep' but not with 'egrep' or 'grep -E') and expecting it to mean 1 or more is a GNU extension, and in this case "there must be a SP after colon" is much easier to see, which is what the updated one uses. Good. By the way, you can drop the ".*" at the end of the pattern, because the match is not anchored at the tail end.
local bad_combo_regex="^fatal: '[a-z-]\+' and '[a-z-]\+' cannot be used together" &&
This should also be corrected, I think.
"fatal: '[a-z-]\{1,\}' and '[a-z-]\{1,\}' cannot be used together"
or even simpler,
"fatal: '[a-z-]*' and '[a-z-]*' cannot be used together"
to avoid \+ in BRE (see above). "[-a-z]" (to show '-' at the
beginning) may make it easier to read by letting the hyphen-minus
stand out more, as we know we are giving two command line option
names and in a command line option name, the first letter is always
hyphen-minus. But that is more of personal taste, not correctness.
quoted hunk
@@ -998,8 +998,8 @@ test_dwim_orphan () { headpath=$(git $dashc_args rev-parse --path-format=absolute --git-path HEAD) && headcontents=$(cat "$headpath") && grep "HEAD points to an invalid (or orphaned) reference" actual && - grep "HEAD path:\s*.$headpath." actual && - grep "HEAD contents:\s*.$headcontents." actual && + grep "HEAD path: .$headpath." actual && + grep "HEAD contents: .$headcontents." actual && grep "$orphan_hint" actual && ! grep "$info_text" actual fi &&
Thanks.