Re: search-default-mode char-fold-to-regexp and Greek Extended block characters

[Robert Pluim]

>>>>> On Thu, 25 Jul 2019 02:12:01 +0300, Juri Linkov <address@hidden> said:
    Juri> This is an interesting case like (upcase "ß") => "SS" that required
    Juri> adding (?ß "ss") to pass the tests.  So I guess we need to add (?ι 
"ΐ")
    Juri> for the tests to pass:

This is OK

    Juri> diff --git a/test/lisp/char-fold-tests.el 
b/test/lisp/char-fold-tests.el
    Juri> index e519435ef0..3819f3919d 100644
    Juri> --- a/test/lisp/char-fold-tests.el
    Juri> +++ b/test/lisp/char-fold-tests.el
    Juri> @@ -166,6 +165,7 @@ char-fold--test-with-customization
    Juri>    (let* ((char-fold-include
    Juri>            '(
    Juri>              (?ß "ss") ;; de
    Juri> +            (?ι "ΐ")  ;; el
    Juri>              (?o "ø")  ;; da no nb nn
    Juri>              (?l "ł")  ;; pl
    Juri>              ))
    Juri> @@ -184,9 +184,7 @@ char-fold--test-with-customization
    Juri>            '(
    Juri>              ("e" "ℯ" "ḗ" "ë" "ë")
    Juri>              ("е" "ё" "ё")
    Juri> -            ("ι" "ί" "ί"
    Juri> -             ;; FIXME: "ΐ"
    Juri> -             )
    Juri> +            ("ι" "ί" "ί" "ΐ")
    Juri>              ("ß" "ss")
    Juri>              ("o" "ø")
    Juri>              ("l" "ł")


    Juri> But this is only for char-fold--test-with-customization.  OTOH, for
    Juri> char-fold--test-without-customization we need also to change the 
default
    Juri> value in char-fold.el like:

    Juri> diff --git a/lisp/char-fold.el b/lisp/char-fold.el
    Juri> index f379229e6c..c4add03bd9 100644
    Juri> --- a/lisp/char-fold.el
    Juri> +++ b/lisp/char-fold.el
    Juri> @@ -27,7 +27,8 @@
    Juri>    (defconst char-fold--default-include
    Juri>      '((?\" "＂" "“" "”" "”" "„" "⹂" "〞" "‟" "‟" "❞" "❝" "❠" "“" "„" 
"〝" "〟" "🙷" "🙶" "🙸" "«" "»")
    Juri>        (?' "❟" "❛" "❜" "‘" "’" "‚" "‛" "‚" "󠀢" "❮" "❯" "‹" "›")
    Juri> -      (?` "❛" "‘" "‛" "󠀢" "❮" "‹")))
    Juri> +      (?` "❛" "‘" "‛" "󠀢" "❮" "‹")
    Juri> +      (?ι "ΐ")))
    Juri>    (defconst char-fold--default-exclude nil)
    Juri>    (defconst char-fold--default-symmetric nil)
    Juri>    (defconst char-fold--previous (list char-fold--default-include

But this one I donʼt understand. Searching for iota (capital or small)
in a buffer containing ΐ ΐ or Ϊ́ already works with
char-fold-to-regexp, so why is this needed?

Robert