54313: convfloat: use consistent capitalisation for NaN, Inf, and -Inf

makes `typeset -p` use the same capitalisation as arithmetic expansion

ChangeLog

@@ -1,3 +1,8 @@
+2026-04-13  dana  <dana@dana.is>
+
+	* 54313: README, Src/params.c, Test/B02typeset.ztst: convfloat:
+	use consistent capitalisation for NaN, Inf, and -Inf
+
 2026-04-13  Jun-ichi Takimoto  <takimoto-j@kba.biglobe.ne.jp>
 
 	* 54327: Completion/Zsh/Type/_parameters: names with dot are

README

@@ -132,6 +132,10 @@ The zsh/datetime module's strftime builtin now exports a set-but-empty
 TZ parameter (as in `TZ= strftime ...`) for use by the underlying
 library.  On most systems, this is equivalent to setting TZ to UTC.
 
+The typeset builtin now prints the floating-point values NaN, Inf, and
+-Inf using that capitalisation, which matches the capitalisation used by
+arithmetic expansion.  (Previously they were printed in lowercase.)
+
 Incompatibilities between 5.8.1 and 5.9
 ---------------------------------------
 

Src/params.c

@@ -5752,7 +5752,12 @@ convfloat(double dval, int digits, int flags, FILE *fout)
     setlocale(LC_NUMERIC, "POSIX");
 #endif
     if (fout) {
-	fprintf(fout, fmt, digits, dval);
+	if (isinf(dval))
+	    fprintf(fout, (dval < 0.0) ? "-Inf" : "Inf");
+	else if (isnan(dval))
+	    fprintf(fout, "NaN");
+	else
+	    fprintf(fout, fmt, digits, dval);
 	ret = NULL;
     } else {
 	VARARR(char, buf, 512 + digits);

Test/B02typeset.ztst

@@ -1177,3 +1177,12 @@ F:This is a bug, the non -h variable should not hide the autoload variable
 >z=SRANDOM (zsh/random)
 >z=
 >v=
+
+ () {
+   typeset -F f1=nan f2=inf f3=-inf
+   typeset -p f1 f2 f3
+ }
+0:float NaN/Inf output formatting
+>typeset -F f1=NaN
+>typeset -F f2=Inf
+>typeset -F f3=-Inf