From e2e8a05bf18435b1814f1bc2f090301eb97281e0 Mon Sep 17 00:00:00 2001
From: Chris Hanson <org/chris-hanson/cph>
Date: Fri, 10 Feb 2017 23:52:19 -0800
Subject: [PATCH] Implement char-{down,fold,up}case-full and use in ustring.

---
 src/runtime/char.scm    | 23 +++++++++++++++++++----
 src/runtime/runtime.pkg | 17 ++++++++++-------
 src/runtime/ustring.scm | 21 ++++++++++-----------
 3 files changed, 39 insertions(+), 22 deletions(-)

diff --git a/src/runtime/char.scm b/src/runtime/char.scm
index d24e855e7..62902286b 100644
--- a/src/runtime/char.scm
+++ b/src/runtime/char.scm
@@ -132,21 +132,36 @@ USA.
   (guarantee char? char 'char-ci=-predicate)
   (lambda (char*)
     (char-ci=? char* char)))
-
+
 (define (char-downcase char)
-  (guarantee unicode-char? char 'char-downcase)
+  (if (not (unicode-scalar-value? (char-code char)))
+      (error:not-a unicode-char? char 'char-downcase))
   (%make-char (ucd-slc-value (char-code char))
 	      (char-bits char)))
 
 (define (char-foldcase char)
-  (guarantee unicode-char? char 'char-foldcase)
+  (if (not (unicode-scalar-value? (char-code char)))
+      (error:not-a unicode-char? char 'char-foldcase))
   (%make-char (ucd-scf-value (char-code char))
 	      (char-bits char)))
 
 (define (char-upcase char)
-  (guarantee unicode-char? char 'char-upcase)
+  (if (not (unicode-scalar-value? (char-code char)))
+      (error:not-a unicode-char? char 'char-upcase))
   (%make-char (ucd-suc-value (char-code char))
 	      (char-bits char)))
+
+(define (char-downcase-full char)
+  (guarantee unicode-char? char 'char-downcase-full)
+  (map integer->char (ucd-lc-value (char->integer char))))
+
+(define (char-foldcase-full char)
+  (guarantee unicode-char? char 'char-foldcase-full)
+  (map integer->char (ucd-cf-value (char->integer char))))
+
+(define (char-upcase-full char)
+  (guarantee unicode-char? char 'char-upcase-full)
+  (map integer->char (ucd-uc-value (char->integer char))))
 
 (define-deferred 0-code (char->integer #\0))
 ;; Next two codes are offset by 10 to speed up CHAR->DIGIT.
diff --git a/src/runtime/runtime.pkg b/src/runtime/runtime.pkg
index e0135d85e..4977f2983 100644
--- a/src/runtime/runtime.pkg
+++ b/src/runtime/runtime.pkg
@@ -1398,7 +1398,11 @@ USA.
 	  unicode-code-point-general-category
 	  unicode-code-point?
 	  unicode-scalar-value->char
-	  unicode-scalar-value?))
+	  unicode-scalar-value?)
+  (export (runtime)
+	  char-downcase-full
+	  char-foldcase-full
+	  char-upcase-full))
 
 (define-package (runtime ucd-tables)
   (files "ucd-table-alpha"
@@ -1420,16 +1424,15 @@ USA.
 	  char-set:lower-case
 	  char-set:upper-case)
   (export (runtime character)
+	  ucd-cf-value
 	  ucd-gc-value
+	  ucd-lc-value
 	  ucd-scf-value
 	  ucd-slc-value
-	  ucd-suc-value)
+	  ucd-suc-value
+	  ucd-uc-value)
   (export (runtime ucd-table-glue)
-	  ucd-nt-value)
-  (export (runtime ustring)
-	  ucd-cf-value
-	  ucd-lc-value
-	  ucd-uc-value))
+	  ucd-nt-value))
 
 (define-package (runtime ucd-table-glue)
   (files "ucd-table-glue")
diff --git a/src/runtime/ustring.scm b/src/runtime/ustring.scm
index 170a51b61..e0b48e7ae 100644
--- a/src/runtime/ustring.scm
+++ b/src/runtime/ustring.scm
@@ -237,25 +237,24 @@ USA.
 		      strings))))))
 
 (define (utf32-string-downcase string)
-  (utf32-case-transform string ucd-lc-value 'utf32-string-downcase))
+  (utf32-case-transform string char-downcase-full 'utf32-string-downcase))
 
 (define (utf32-string-foldcase string)
-  (utf32-case-transform string ucd-cf-value 'utf32-string-foldcase))
+  (utf32-case-transform string char-foldcase-full 'utf32-string-foldcase))
 
 (define (utf32-string-upcase string)
-  (utf32-case-transform string ucd-uc-value 'utf32-string-upcase))
+  (utf32-case-transform string char-upcase-full 'utf32-string-upcase))
 
-(define (utf32-case-transform string sv-transform caller)
-  (let ((svs
-	 (append-map (lambda (char)
-		       (sv-transform (char->integer char)))
+(define (utf32-case-transform string transform caller)
+  (let ((chars
+	 (append-map transform
 		     (utf32-string->list string))))
-    (let ((n (length svs)))
+    (let ((n (length chars)))
       (let ((result (make-utf32-string n)))
-	(do ((svs svs (cdr svs))
+	(do ((chars chars (cdr chars))
 	     (i 0 (fix:+ i 1)))
-	    ((not (pair? svs)))
-	  (utf32-string-set! result i (integer->char (car svs))))
+	    ((not (pair? chars)))
+	  (utf32-string-set! result i (car chars)))
 	result))))
 
 ;; Incorrect, needs title-case implementation
-- 
2.25.1