Correctly block invalid values for arrays of an enum type

This fixes part of https://github.com/ksh93/ksh/issues/87:

Scalar arrays (-a) and associative arrays (-A) of a type created by
'enum' did not consistently block values not specified by the enum
type, yielding corrupted results.

An expansion of type "${array[@]}" yielded random numbers instead
of values for associative arrays of a type created by 'enum'.

This does not yet fix another problem: ${array[@]} does not yield
all values for associative enum arrays.

src/cmd/ksh93/bltins/enum.c: put_enum():
- Always throw an error if the value is not in the list of possible
  values for an enum type. Remove incorrect check for the NV_NOFREE
  flag. Whatever that was meant to accomplish, I've no idea.

src/cmd/ksh93/sh/array.c: nv_arraysettype():
- Instead of sh_eval()ing a shell assignment, use nv_putval()
  directly. Also use the stack (see src/lib/libast/man/stk.3)
  instead of malloc to save the value; it's faster and will be
  auto-freed at some point. This shortens the function and makes it
  faster by not entering into a whole new shell context -- which
  also fixes another problem: the error message from put_enum()
  didn't cause the shell to exit for indexed enum arrays.

src/cmd/ksh93/sh/name.c: nv_setlist():
- Apply a patch from David Korn that correctly sets the data type
  for associative arrays, fixing the ${array[@]} expansion yielding
  random numbers. Thanks to @JohnoKing for the pointer.
  https://github.com/ksh93/ksh/issues/87#issuecomment-662613887
  https://www.mail-archive.com/ast-developers@lists.research.att.com/msg00697.html

src/cmd/ksh93/tests/enum.sh:
- Add tests checking that invalid values are correctly blocked for
  indexed and associative arrays of an enum type.

Makes progress on: https://github.com/ksh93/ksh/issues/87

src/cmd/ksh93/bltins/enum.c

@@ -150,8 +150,7 @@ static void put_enum(Namval_t* np,const char *val,int flags,Namfun_t *fp)
 		}
 		i++;
 	}
-	if(nv_isattr(np,NV_NOFREE))
-		error(ERROR_exit(1), "%s: invalid value %s",nv_name(np),val);
+	error(ERROR_exit(1), "%s: invalid value %s",nv_name(np),val);
 }
 
 static char* get_enum(register Namval_t* np, Namfun_t *fp)

src/cmd/ksh93/include/version.h

@@ -20,7 +20,7 @@
 
 #define SH_RELEASE_FORK	"93u+m"		/* only change if you develop a new ksh93 fork */
 #define SH_RELEASE_SVER	"1.0.0-alpha"	/* semantic version number: https://semver.org */
-#define SH_RELEASE_DATE	"2021-01-31"	/* must be in this format for $((.sh.version)) */
+#define SH_RELEASE_DATE	"2021-02-01"	/* must be in this format for $((.sh.version)) */
 #define SH_RELEASE_CPYR	"(c) 2020-2021 Contributors to ksh " SH_RELEASE_FORK
 
 /* Scripts sometimes field-split ${.sh.version}, so don't change amount of whitespace. */

src/cmd/ksh93/sh/array.c

@@ -407,11 +407,7 @@ static Namval_t *array_find(Namval_t *np,Namarr_t *arp, int flag)
 int nv_arraysettype(Namval_t *np, Namval_t *tp, const char *sub, int flags)
 {
 	Namval_t	*nq;
-	char		*av[2];
-	int		rdonly = nv_isattr(np,NV_RDONLY);
-	int		xtrace = sh_isoption(SH_XTRACE);
 	Namarr_t	*ap = nv_arrayptr(np);
-	av[1] = 0;
 	sh.last_table = 0;
 	if(!ap->table)
 	{
@@ -420,30 +416,20 @@ int nv_arraysettype(Namval_t *np, Namval_t *tp, const char *sub, int flags)
 	}
 	if(nq = nv_search(sub, ap->table, NV_ADD))
 	{
+		char		*saved_value;
+		int		rdonly = nv_isattr(np,NV_RDONLY);
 		if(!nq->nvfun && nq->nvalue.cp && *nq->nvalue.cp==0)
 			_nv_unset(nq,NV_RDONLY);
 		nv_arraychild(np,nq,0);
 		if(!nv_isattr(tp,NV_BINARY))
-		{
-			sfprintf(sh.strbuf,"%s=%s",nv_name(nq),nv_getval(np));
-			av[0] = strdup(sfstruse(sh.strbuf));
-		}
+			saved_value = stkcopy(stkstd,nv_getval(np));
 		if(!nv_clone(tp,nq,flags|NV_NOFREE))
 			return(0);
-		ap->nelem |= ARRAY_SCAN;
 		if(!rdonly)
 			nv_offattr(nq,NV_RDONLY);
 		if(!nv_isattr(tp,NV_BINARY))
-		{
-			if(xtrace)
-				sh_offoption(SH_XTRACE);
-			ap->nelem &= ~ARRAY_SCAN;
-			sh_eval(sh_sfeval(av),0);
-			ap->nelem |= ARRAY_SCAN;
-			free((void*)av[0]);
-			if(xtrace)
-				sh_onoption(SH_XTRACE);
-		}
+			nv_putval(nq,saved_value,0);
+		ap->nelem |= ARRAY_SCAN;
 		return(1);
 	}
 	return(0);

src/cmd/ksh93/sh/name.c

@@ -389,6 +389,8 @@ void nv_setlist(register struct argnod *arg,register int flags, Namval_t *typ)
 					if(array&NV_ARRAY)
 					{
 						nv_setarray(np,nv_associative);
+						if(typ)
+							nv_settype(np,typ,0);
 					}
 					else
 					{

src/cmd/ksh93/tests/enum.sh

@@ -74,4 +74,16 @@ arr[green]=foo
 read -A arr <<<  'x y z xx yy'
 [[ ${arr[1]} == ${arr[green]}  ]] || err_exit 'arr[1] != arr[green] after read'
 
+# enum arrays didn't block unspecified values
+# https://github.com/ksh93/ksh/issues/87
+exp=': Color_t: clr[2]: invalid value WRONG'
+got=$(set +x; redirect 2>&1; Color_t -a clr=(red blue WRONG yellow); printf '%s\n' "${clr[@]}")
+(((e = $?) == 1)) && [[ $got == *"$exp" ]] || err_exit "indexed enum array, unspecified value:" \
+	"expected status 1, *$(printf %q "$exp"); got status $e, $(printf %q "$got")"
+exp=': clr: invalid value BAD'
+got=$(set +x; redirect 2>&1; Color_t -A clr=([foo]=red [bar]=blue [bad]=BAD); printf '%s\n' "${clr[@]}")
+(((e = $?) == 1)) && [[ $got == *"$exp" ]] || err_exit "associative enum array, unspecified value:" \
+	"expected status 1, *$(printf %q "$exp"); got status $e, $(printf %q "$got")"
+
+# ======
 exit $((Errors<125?Errors:125))