[PATCH] t2400: Fix test failures when using grep 2.5

[Jacob Abel <jacobabel@nullpo.dev>]

Replace all cases of `\s` with `[[:space:]]` as older versions of GNU
grep (and from what it seems most versions of BSD grep) do not handle
`\s`.

For the same reason all cases of `\S` are replaced with `[^[:space:]]`.
Replacing `\S` also needs to occur as `\S` is technically PCRE and not
part of ERE even though most modern versions of grep accept it as ERE.

Signed-off-by: Jacob Abel <jacobabel@nullpo.dev>
---
This patch is in response to build failures on GGG's Cirrus CI 
freebsd_12 build jobs[1] and was prompted by a discussion thread [2].

These failures seem to be caused by the behavior outlined in [3]. 
Weirdly however they only seem to occur on the FreeBSD CI but not the 
Mac OS CI for some reason despite Mac OS using FreeBSD grep.

1. https://github.com/gitgitgadget/git/pull/1550/checks?check_run_id=14949695859
2. https://lore.kernel.org/git/CALnO6CDryTsguLshcQxx97ZxyY42Twu2hC2y1bLOsS-9zbqXMA@mail.gmail.com/
3. https://stackoverflow.com/questions/4233159/grep-regex-whitespace-behavior

 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 0ac468e69e..7f19bdabff 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:[[:space:]]+git worktree add --orphan -b [^[:space:]]+ [^[:space:]]+[[:space:]]*$" actual
 		else
-			grep -E "^hint:\s+git worktree add --orphan \S+\s*$" actual
+			grep -E "^hint:[[:space:]]+git worktree add --orphan [^[:space:]]+[[:space:]]*$" actual
 		fi
 
 	'
@@ -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:[[:space:]]\+.*" &&
 	local bad_combo_regex="^fatal: '[a-z-]\+' and '[a-z-]\+' cannot be used together" &&
 
 	local git_ns="repo" &&
@@ -998,8 +998,8 @@ test_dwim_orphan () {
 					headpath=$(git $dashc_args rev-parse --sq --path-format=absolute --git-path HEAD) &&
 					headcontents=$(cat "$headpath") &&
 					grep "HEAD points to an invalid (or orphaned) reference" actual &&
-					grep "HEAD path:\s*.$headpath." actual &&
-					grep "HEAD contents:\s*.$headcontents." actual &&
+					grep "HEAD path:[[:space:]]*.$headpath." actual &&
+					grep "HEAD contents:[[:space:]]*.$headcontents." actual &&
 					grep "$orphan_hint" actual &&
 					! grep "$info_text" actual
 				fi &&

base-commit: 830b4a04c45bf0a6db26defe02ed1f490acd18ee
-- 
2.39.3