Bug fixes to non-MULE compatibility code

src/ChangeLog

+1999-12-01  David Byers  <davby@ida.liu.se>
+
+	* compatibility.el (decode-coding-string, encode-coding-string):
+	Copy the string using copy-sequence to really emulate the real
+	thing.
+
+	* utilities.el (lyskom-string=):  Works even if an argument is
+	nil.
+
 Thu Nov 25 17:05:19 1999  David Byers  <davby@sen2.ida.liu.se>
 
 	* Release av 0.46-BETA-C p riktigt

src/compatibility.el

@@ -301,8 +301,8 @@ string to search in."
 (lyskom-provide-function set-process-coding-system (proc &optional encoding decoding)
   )
 
-(lyskom-provide-function encode-coding-string (str coding-system) str)
-(lyskom-provide-function decode-coding-string (str coding-system) str)
+(lyskom-provide-function encode-coding-string (str coding-system) (copy-sequence str))
+(lyskom-provide-function decode-coding-string (str coding-system) (copy-sequence str))
 (lyskom-provide-function string-bytes (str) (length str))
 (lyskom-provide-function check-coding-system (name) (error "No such coding system"))
 (lyskom-provide-function string-width (str) (length str))

src/utilities.el

@@ -373,14 +373,14 @@ the resulting string may be narrower than END-COLUMN."
    (if (< emacs-major-version 20)
        (fset 'lyskom-string= (symbol-function 'string=))
      (defun lyskom-string= (s1 s2)
-       (string= (if (multibyte-string-p s1)
+       (string= (and s1 (if (multibyte-string-p s1)
 		    s1
 		  (decode-coding-string s1 (lyskom-language-coding
-					    lyskom-language)))
-		(if (multibyte-string-p s2)
+					    lyskom-language))))
+		(and s2 (if (multibyte-string-p s2)
 		    s2
 		  (decode-coding-string s2 (lyskom-language-coding
-					    lyskom-language))))))))
+					    lyskom-language)))))))))
 
 (defun lyskom-string-assoc (key list)
   "Return non-nil if KEY is the same string as the car of an element of LIST.