v12-0002-Remove-unused-single-byte-char_is_cased-API.patch

From 48620dadcfeec2880575c963441bb1dd017802f0 Mon Sep 17 00:00:00 2001
From: Jeff Davis <jeff@j-davis.com>
Date: Fri, 12 Dec 2025 09:44:59 -0800
Subject: [PATCH v12 2/8] Remove unused single-byte char_is_cased() API.

https://postgr.es/m/450ceb6260cad30d7afdf155d991a9caafee7c0d.camel@j-davis.com
---
 src/backend/utils/adt/pg_locale.c         | 15 ---------------
 src/backend/utils/adt/pg_locale_builtin.c |  8 --------
 src/backend/utils/adt/pg_locale_icu.c     |  8 --------
 src/backend/utils/adt/pg_locale_libc.c    | 14 --------------
 src/include/utils/pg_locale.h             |  3 ---
 5 files changed, 48 deletions(-)

diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index 70933ee3843..8a3796aa5d0 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/src/backend/utils/adt/pg_locale.c
@@ -1625,21 +1625,6 @@ pg_towlower(pg_wchar wc, pg_locale_t locale)
 		return locale->ctype->wc_tolower(wc, locale);
 }
 
-/*
- * char_is_cased()
- *
- * Fuzzy test of whether the given char is case-varying or not. The argument
- * is a single byte, so in a multibyte encoding, just assume any non-ASCII
- * char is case-varying.
- */
-bool
-char_is_cased(char ch, pg_locale_t locale)
-{
-	if (locale->ctype == NULL)
-		return (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
-	return locale->ctype->char_is_cased(ch, locale);
-}
-
 /*
  * Return required encoding ID for the given locale, or -1 if any encoding is
  * valid for the locale.
diff --git a/src/backend/utils/adt/pg_locale_builtin.c b/src/backend/utils/adt/pg_locale_builtin.c
index 0d4c754a267..0c2920112bb 100644
--- a/src/backend/utils/adt/pg_locale_builtin.c
+++ b/src/backend/utils/adt/pg_locale_builtin.c
@@ -191,13 +191,6 @@ wc_iscased_builtin(pg_wchar wc, pg_locale_t locale)
 	return pg_u_prop_cased(to_char32(wc));
 }
 
-static bool
-char_is_cased_builtin(char ch, pg_locale_t locale)
-{
-	return IS_HIGHBIT_SET(ch) ||
-		(ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
-}
-
 static pg_wchar
 wc_toupper_builtin(pg_wchar wc, pg_locale_t locale)
 {
@@ -225,7 +218,6 @@ static const struct ctype_methods ctype_methods_builtin = {
 	.wc_ispunct = wc_ispunct_builtin,
 	.wc_isspace = wc_isspace_builtin,
 	.wc_isxdigit = wc_isxdigit_builtin,
-	.char_is_cased = char_is_cased_builtin,
 	.wc_iscased = wc_iscased_builtin,
 	.wc_tolower = wc_tolower_builtin,
 	.wc_toupper = wc_toupper_builtin,
diff --git a/src/backend/utils/adt/pg_locale_icu.c b/src/backend/utils/adt/pg_locale_icu.c
index e8820666b2d..18d026deda8 100644
--- a/src/backend/utils/adt/pg_locale_icu.c
+++ b/src/backend/utils/adt/pg_locale_icu.c
@@ -121,13 +121,6 @@ static int32_t u_strFoldCase_default(UChar *dest, int32_t destCapacity,
 									 const char *locale,
 									 UErrorCode *pErrorCode);
 
-static bool
-char_is_cased_icu(char ch, pg_locale_t locale)
-{
-	return IS_HIGHBIT_SET(ch) ||
-		(ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
-}
-
 /*
  * XXX: many of the functions below rely on casts directly from pg_wchar to
  * UChar32, which is correct for the UTF-8 encoding, but not in general.
@@ -244,7 +237,6 @@ static const struct ctype_methods ctype_methods_icu = {
 	.wc_ispunct = wc_ispunct_icu,
 	.wc_isspace = wc_isspace_icu,
 	.wc_isxdigit = wc_isxdigit_icu,
-	.char_is_cased = char_is_cased_icu,
 	.wc_iscased = wc_iscased_icu,
 	.wc_toupper = toupper_icu,
 	.wc_tolower = tolower_icu,
diff --git a/src/backend/utils/adt/pg_locale_libc.c b/src/backend/utils/adt/pg_locale_libc.c
index 3d841f818a5..3baa5816b5f 100644
--- a/src/backend/utils/adt/pg_locale_libc.c
+++ b/src/backend/utils/adt/pg_locale_libc.c
@@ -262,17 +262,6 @@ wc_iscased_libc_mb(pg_wchar wc, pg_locale_t locale)
 		iswlower_l((wint_t) wc, locale->lt);
 }
 
-static bool
-char_is_cased_libc(char ch, pg_locale_t locale)
-{
-	bool		is_multibyte = pg_database_encoding_max_length() > 1;
-
-	if (is_multibyte && IS_HIGHBIT_SET(ch))
-		return true;
-	else
-		return isalpha_l((unsigned char) ch, locale->lt);
-}
-
 static pg_wchar
 toupper_libc_sb(pg_wchar wc, pg_locale_t locale)
 {
@@ -345,7 +334,6 @@ static const struct ctype_methods ctype_methods_libc_sb = {
 	.wc_ispunct = wc_ispunct_libc_sb,
 	.wc_isspace = wc_isspace_libc_sb,
 	.wc_isxdigit = wc_isxdigit_libc_sb,
-	.char_is_cased = char_is_cased_libc,
 	.wc_iscased = wc_iscased_libc_sb,
 	.wc_toupper = toupper_libc_sb,
 	.wc_tolower = tolower_libc_sb,
@@ -371,7 +359,6 @@ static const struct ctype_methods ctype_methods_libc_other_mb = {
 	.wc_ispunct = wc_ispunct_libc_sb,
 	.wc_isspace = wc_isspace_libc_sb,
 	.wc_isxdigit = wc_isxdigit_libc_sb,
-	.char_is_cased = char_is_cased_libc,
 	.wc_iscased = wc_iscased_libc_sb,
 	.wc_toupper = toupper_libc_sb,
 	.wc_tolower = tolower_libc_sb,
@@ -393,7 +380,6 @@ static const struct ctype_methods ctype_methods_libc_utf8 = {
 	.wc_ispunct = wc_ispunct_libc_mb,
 	.wc_isspace = wc_isspace_libc_mb,
 	.wc_isxdigit = wc_isxdigit_libc_mb,
-	.char_is_cased = char_is_cased_libc,
 	.wc_iscased = wc_iscased_libc_mb,
 	.wc_toupper = toupper_libc_mb,
 	.wc_tolower = tolower_libc_mb,
diff --git a/src/include/utils/pg_locale.h b/src/include/utils/pg_locale.h
index 832007385d8..01f891def7a 100644
--- a/src/include/utils/pg_locale.h
+++ b/src/include/utils/pg_locale.h
@@ -125,9 +125,6 @@ struct ctype_methods
 	bool		(*wc_iscased) (pg_wchar wc, pg_locale_t locale);
 	pg_wchar	(*wc_toupper) (pg_wchar wc, pg_locale_t locale);
 	pg_wchar	(*wc_tolower) (pg_wchar wc, pg_locale_t locale);
-
-	/* required */
-	bool		(*char_is_cased) (char ch, pg_locale_t locale);
 };
 
 /*
-- 
2.43.0