completing-read doesn't show or select candidate correctly if differently cased

[cosmicexplorer]

Two failure cases (at least, differences from completing-read-default that look like errors):

(let ((completion-ignore-case nil))
  (helm--completing-read-default
   "hey: " '("wow" "nice" "yay")))

Inserting WOW into the helm buffer and pressing RET returns "", and it should return "WOW" unless I'm mistaken. The same occurs with REQUIRE-MATCH set to 'confirm or anything else except t.

(let ((completion-ignore-case t))
  (helm--completing-read-default
   "hey: " '("wow" "nice" "yay")))

Inserting "W" should also show "wow" as a candidate because of completion-ignore-case (as it does with completing-read-default), but it doesn't. It also returns "" here when "WOW" is the helm-pattern; it should return "WOW" (in accordance with completing-read-default).

I'll try to look into these soon but I'm not super familiar with the codebase so it'll take me a bit. Are either of these supposed to be happening?

[thierryvolpiatto]

Danny McClanahan notifications@github.com writes:

Two failure cases (at least, differences from completing-read-default that look like errors):

(let ((completion-ignore-case nil))
(helm--completing-read-default

First of all, please do not use helm--completing-read-default, it is for
internal use, use instead completing-read with helm-mode enabled.

"hey: " '("wow" "nice" "yay")))

Inserting WOW into the helm buffer and pressing RET returns "", and it
should return "WOW" unless I'm mistaken.

Helm is ignoring completion-ignore-case, it is using the following
variables:

For generic completion i.e completing-read and read-file-name and
friends:

• helm-comp-read-case-fold-search
• helm-file-name-case-fold-search (used also in native helm files
  related commands)

For helm more generally:

• helm-case-fold-search

Both helm-comp-read-case-fold-search and helm-file-name-case-fold-search
are set by default to the default value of helm-case-fold-search which
is 'smart which see.

See following examples:

(let ((helm-comp-read-case-fold-search t))
(completing-read "test: " '("wow" "nice" "yay")))

(let ((helm-case-fold-search t))
(helm :sources (helm-build-in-buffer-source "test"
:data '("wow" "nice" "yay"))
:buffer "helm test"))

(let ((helm-case-fold-search t))
(helm :sources (helm-build-sync-source "test"
:candidates '("wow" "nice" "yay"))
:buffer "helm test"))

Thierry