On 23/07/21 08:16AM, Junio C Hamano wrote:

Jacob Abel [off-list ref] writes:

quoted

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.

Using `[ ]` over ` ` is just a personal thing I picked up to keep
myself from forgetting the space was intentional. I can see how that
can come across as confusing though so I'll make sure to update that.

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.

Good point. Will do.

[...]

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.

Noted.

quoted

@@ -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, 

Oh it is. I've really gotta reread the chapters of the POSIX standard
on regex again.

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.

Understood.

quoted

 	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).  

I definitely prefer the latter so I'll update it to use that one.

"[-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.

Certainly a matter of personal preference but I can see why this
could be preferable so I'll update it to this.

[...]