Fix the output of typeset -p for two dimensional indexed arrays (#454)

In ksh93v- 2012-10-04 the following bugfix is noted in the changelog
(this fix was most likely part of ksh93v- 2012-09-27, although that
version is not archived anywhere):
12-09-21  A bug in which the output of a two dimensional sparse
          indexed array would cause the second subscript be treated
          as an associative array when read back in has been fixed.
          Elements that are sparse indexed arrays now are prefixed
          type "typeset -a".

Below is a before and after of this change:

   # Before
   $ typeset -a foo[1][2]=bar
   $ typeset -p foo
   typeset -a foo=([1]=([2]=bar) )

   # After
   $ typeset -a foo[1][2]=bar
   $ typeset -p foo
   typeset -a foo=(typeset -a [1]=([2]=bar) )

src/cmd/ksh93/sh/*.c:
- Backport changes from ksh93v- to print 'typeset -a' before sparse
  indexed arrays and properly handle 'typeset -a' in reinput
  commands from 'typeset -p'.

src/cmd/ksh93/tests:
- Add two regression tests to arrays.sh for this change.
- Update the existing regression tests for compatibility with the
  new printed typeset output.

NEWS

@@ -14,6 +14,11 @@ Any uppercase BUG_* names are modernish shell bug IDs.
   an incompletely defined 'foo_t' built-in comamnd that will crash the shell
   when used. Instead, it is now silently ignored for backwards compatibility.
 
+- A bug in which the output of a two dimensional sparse indexed array would
+  cause the second subscript to be treated as an associative array when read
+  back in has been fixed. Elements that are sparse indexed arrays are now
+  prefixed with "typeset -a".
+
 2022-02-05:
 
 - Fixed: for indexed arrays, given an unset array member a[i] with i > 0,

src/cmd/ksh93/include/argnod.h

@@ -120,6 +120,7 @@ struct argnod
 #define ARG_QUOTED	0x20	/* word contained quote characters */
 #define ARG_MESSAGE	0x40	/* contains international string */
 #define ARG_APPEND	0x80	/* for += assignment */
+#define ARG_ARRAY	0x2	/* for typeset -a */
 /* The following can be passed as options to sh_macexpand() */
 #define ARG_ARITH	0x100	/* arithmetic expansion */
 #define ARG_OPTIMIZE	0x200	/* try to optimize */

src/cmd/ksh93/include/shlex.h

@@ -90,6 +90,7 @@ typedef struct  _shlex_
 	char		noreserv;	/* reserved works not legal */
 	int		inlineno;	/* saved value of sh.inlineno */
 	int		firstline;	/* saved value of sh.st.firstline */
+	int		assignlevel;	/* nesting level for assignment */
 #if SHOPT_KIA
 	Sfio_t		*kiafile;	/* kia output file */
 	Sfio_t		*kiatmp;	/* kia reference file */

src/cmd/ksh93/sh/name.c

@@ -308,13 +308,15 @@ void nv_setlist(register struct argnod *arg,register int flags, Namval_t *typ)
 		else
 		{
 			stakseek(0);
-			if(*arg->argval==0 && arg->argchn.ap && !(arg->argflag&~(ARG_APPEND|ARG_QUOTED|ARG_MESSAGE)))
+			if(*arg->argval==0 && arg->argchn.ap && !(arg->argflag&~(ARG_APPEND|ARG_QUOTED|ARG_MESSAGE|ARG_ARRAY)))
 			{
 				int flag = (NV_VARNAME|NV_ARRAY|NV_ASSIGN);
 				int sub=0;
 				struct fornod *fp=(struct fornod*)arg->argchn.ap;
 				register Shnode_t *tp=fp->fortre;
 				flag |= (flags&(NV_NOSCOPE|NV_STATIC|NV_FARRAY));
+				if(arg->argflag&ARG_ARRAY)
+					array |= NV_IARRAY;
 				if(arg->argflag&ARG_QUOTED)
 					cp = sh_mactrim(fp->fornam,-1);
 				else

src/cmd/ksh93/sh/nvtree.c

@@ -587,6 +587,9 @@ void nv_outnode(Namval_t *np, Sfio_t* out, int indent, int special)
 		tabs=0;
 		if(associative||special)
 		{
+			Namarr_t *aq;
+			if(mp && (aq=nv_arrayptr(mp)) && !aq->fun && array_elem(aq) < nv_aimax(mp)+1)
+				sfwrite(out,"typeset -a ",11);
 			if(!(fmtq = nv_getsub(np)))
 				break;
 			sfprintf(out,"[%s]",sh_fmtq(fmtq));

src/cmd/ksh93/sh/parse.c

@@ -377,6 +377,7 @@ void	*sh_parse(Sfio_t *iop, int flag)
 		return((void*)sh_trestore(iop));
 	fcsave(&sav_input);
 	sh.st.staklist = 0;
+	lexp->assignlevel = 0;
 	lexp->noreserv = 0;
 	lexp->heredoc = 0;
 	lexp->inlineno = sh.inlineno;
@@ -967,6 +968,30 @@ static Shnode_t *funct(Lex_t *lexp)
 	return(t);
 }
 
+static int check_array(Lex_t *lexp)
+{
+	int n,c;
+	if(lexp->token==0 && strcmp(lexp->arg->argval, SYSTYPESET->nvname)==0)
+	{
+		while((c=fcgetc(n))==' ' || c=='\t');
+		if(c=='-')
+		{
+			if(fcgetc(n)=='a')
+			{
+				lexp->assignok = SH_ASSIGN;
+				lexp->noreserv = 1;
+				sh_lex(lexp);
+				return(1);
+			}
+			else
+				fcseek(-2);
+		}
+		else
+			fcseek(-1);
+	}
+	return(0);
+}
+
 /*
  * Compound assignment
  */
@@ -978,6 +1003,7 @@ static struct argnod *assign(Lex_t *lexp, register struct argnod *ap, int type)
 	Stk_t	*stkp = sh.stk;
 	int array=0, index=0;
 	Namval_t *np;
+	lexp->assignlevel++;
 	n = strlen(ap->argval)-1;
 	if(ap->argval[n]!='=')
 		sh_syntax(lexp);
@@ -1002,14 +1028,14 @@ static struct argnod *assign(Lex_t *lexp, register struct argnod *ap, int type)
 	ap->argflag &= ARG_QUOTED;
 	ap->argflag |= array;
 	lexp->assignok = SH_ASSIGN;
-	if(type==NV_ARRAY)
+	if(type&NV_ARRAY)
 	{
 		lexp->noreserv = 1;
 		lexp->assignok = 0;
 	}
 	else
 		lexp->aliasok = 2;
-	array= (type==NV_ARRAY)?SH_ARRAY:0;
+	array= (type&NV_ARRAY)?SH_ARRAY:0;
 	if((n=skipnl(lexp,0))==RPAREN || n==LPAREN)
 	{
 		struct argnod *ar,*aq,**settail;
@@ -1148,6 +1174,7 @@ static struct argnod *assign(Lex_t *lexp, register struct argnod *ap, int type)
 	}
 	*tp = (Shnode_t*)ac;
 	lexp->assignok = 0;
+	lexp->assignlevel--;
 	return(ap);
 }
 
@@ -1433,6 +1460,8 @@ static Shnode_t *simple(Lex_t *lexp,int flag, struct ionod *io)
 	struct argnod	**argtail;
 	struct argnod	**settail;
 	int	cmdarg = 0;
+	int	type = 0;
+	int	was_assign = 0;
 	int	argno = 0;
 	int	assignment = 0;
 	int	key_on = (!(flag&SH_NOIO) && sh_isoption(SH_KEYWORD));
@@ -1452,8 +1481,11 @@ static Shnode_t *simple(Lex_t *lexp,int flag, struct ionod *io)
 	t->comnamq = 0;
 	t->comstate = 0;
 	settail = &(t->comset);
+	if(lexp->assignlevel && (flag&SH_ARRAY) && check_array(lexp))
+		type |= NV_ARRAY;
 	while(lexp->token==0)
 	{
+		was_assign = 0;
 		argp = lexp->arg;
 		if(*argp->argval==LBRACE && (flag&SH_FUNDEF) && argp->argval[1]==0)
 		{
@@ -1531,6 +1563,8 @@ static Shnode_t *simple(Lex_t *lexp,int flag, struct ionod *io)
 		}
 	retry:
 		tok = sh_lex(lexp);
+		if(was_assign && check_array(lexp))
+			type = NV_ARRAY;
 		if(tok==LABLSYM && (flag&SH_ASSIGN))
 			lexp->token = tok = 0;
 		if((tok==IPROCSYM || tok==OPROCSYM))
@@ -1546,7 +1580,6 @@ static Shnode_t *simple(Lex_t *lexp,int flag, struct ionod *io)
 			if(argp->argflag&ARG_ASSIGN)
 			{
 				int intypeset = lexp->intypeset;
-				int type = 0;
 				lexp->intypeset = 0;
 				if(t->comnamp == SYSCOMPOUND)
 					type = NV_COMVAR;
@@ -1558,18 +1591,21 @@ static Shnode_t *simple(Lex_t *lexp,int flag, struct ionod *io)
 						if(*ap->argval!='-')
 							break;
 						if(strchr(ap->argval,'T'))
-							type = NV_TYPE;
+							type |= NV_TYPE;
 						else if(strchr(ap->argval,'a'))
-							type = NV_ARRAY;
+							type |= NV_ARRAY;
 						else if(strchr(ap->argval,'C'))
-							type = NV_COMVAR;
+							type |= NV_COMVAR;
 						else
 							continue;
-						break;
 					}
 				}
 				argp = assign(lexp,argp,type);
+				if(type==NV_ARRAY)
+					argp->argflag |= ARG_ARRAY;
 				lexp->intypeset = intypeset;
+				if(lexp->assignlevel)
+					was_assign = 1;
 				if(associative)
 					lexp->assignok |= SH_ASSIGN;
 				goto retry;

src/cmd/ksh93/sh/tdump.c

@@ -160,7 +160,7 @@ static int p_arg(register const struct argnod *arg)
 	struct fornod *fp;
 	while(arg)
 	{
-		if((n = strlen(arg->argval)) || (arg->argflag&~(ARG_APPEND|ARG_MESSAGE|ARG_QUOTED)))
+		if((n = strlen(arg->argval)) || (arg->argflag&~(ARG_APPEND|ARG_MESSAGE|ARG_QUOTED|ARG_ARRAY)))
 			fp=0;
 		else
 		{

src/cmd/ksh93/sh/trestore.c

@@ -195,7 +195,7 @@ static struct argnod *r_arg(void)
 		ap = (struct argnod*)stkfreeze(stkp,0);
 		if(*ap->argval==0 && (ap->argflag&ARG_EXP))
 			ap->argchn.ap = (struct argnod*)r_tree();
-		else if(*ap->argval==0 && (ap->argflag&~(ARG_APPEND|ARG_MESSAGE|ARG_QUOTED))==0)
+		else if(*ap->argval==0 && (ap->argflag&~(ARG_APPEND|ARG_MESSAGE|ARG_QUOTED|ARG_ARRAY))==0)
 		{
 			struct fornod *fp = (struct fornod*)getnode(fornod);
 			fp->fortyp = sfgetu(infile);

src/cmd/ksh93/tests/arrays.sh

@@ -803,5 +803,21 @@ got=$(set +x; redirect 2>&1; foo[42]=''; : ${foo[42]:?})
 [[ $got == *"$exp" ]] || err_exit '${array[index]:?error} does not throw error' \
 	"(expected match of *$(printf %q "$exp"), got $(printf %q "$got"))"
 
+# ======
+# A multidimensional indexed array should be printed correctly by
+# 'typeset -p'. Additionally, the printed command must produce the
+# same result when reinput to the shell.
+unset foo
+typeset -a foo[1][2]=bar
+exp='typeset -a foo=(typeset -a [1]=([2]=bar) )'
+got=$(typeset -p foo)
+[[ $exp == "$got" ]] || err_exit "Multidimensional indexed arrays are not printed correctly with 'typeset -p'" \
+	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+unset foo
+typeset -a foo=(typeset -a [1]=([2]=bar) )
+got=$(typeset -p foo)
+[[ $exp == "$got" ]] || err_exit "Output from 'typeset -p' for indexed array cannot be used for reinput" \
+	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+
 # ======
 exit $((Errors<125?Errors:125))

src/cmd/ksh93/tests/arrays2.sh

@@ -159,7 +159,7 @@ done
 
 $SHELL 2> /dev/null -c 'compound c;float -a c.ar;(( c.ar[2][3][3] = 5))' || 'multidimensional arrays in arithmetic expressions not working'
 
-expected='typeset -a -l -E c.ar=([2]=([3]=([3]=5) ) )'
+expected='typeset -a -l -E c.ar=(typeset -a [2]=(typeset -a [3]=([3]=5) ) )'
 unset c
 float c.ar
 c.ar[2][3][3]=5

src/cmd/ksh93/tests/comvar.sh

@@ -668,7 +668,7 @@ compound  -a c.board
 for ((i=2; i < 4; i++))
 do	c.board[1][$i]=(foo=bar)
 done
-exp=$'(\n\ttypeset -C -a board=(\n\t\t[1]=(\n\t\t\t[2]=(\n\t\t\t\tfoo=bar\n\t\t\t)\n\t\t\t[3]=(\n\t\t\t\tfoo=bar\n\t\t\t)\n\t\t)\n\t)\n)'
+exp=$'(\n\ttypeset -C -a board=(\n\t\ttypeset -a [1]=(\n\t\t\t[2]=(\n\t\t\t\tfoo=bar\n\t\t\t)\n\t\t\t[3]=(\n\t\t\t\tfoo=bar\n\t\t\t)\n\t\t)\n\t)\n)'
 [[ "$(print -v c)" == "$exp" ]] || err_exit 'compound variable assignment to two dimensional array not working'
 
 unset zz

src/cmd/ksh93/tests/nameref.sh

@@ -593,7 +593,7 @@ function read_c
 	read -C v
 }
 print "( typeset -i x=36 ) " | read_c ar[5][9][2]
-exp=$'(\n\t[5]=(\n\t\t[9]=(\n\t\t\t[2]=(\n\t\t\t\ttypeset -i x=36\n\t\t\t)\n\t\t)\n\t)\n)'
+exp=$'(\n\ttypeset -a [5]=(\n\t\ttypeset -a [9]=(\n\t\t\t[2]=(\n\t\t\t\ttypeset -i x=36\n\t\t\t)\n\t\t)\n\t)\n)'
 [[ $(print -v ar) == "$exp" ]] || err_exit 'read into nameref of global array instance from within a function fails'
 
 function read_c
@@ -606,7 +606,7 @@ function main
 	compound -a ar
 	nameref nar=ar
 	print "( typeset -i x=36 ) " | read_c nar[5][9][2]
-	exp=$'(\n\t[5]=(\n\t\t[9]=(\n\t\t\t[2]=(\n\t\t\t\ttypeset -i x=36\n\t\t\t)\n\t\t)\n\t)\n)'
+	exp=$'(\n\ttypeset -a [5]=(\n\t\ttypeset -a [9]=(\n\t\t\t[2]=(\n\t\t\t\ttypeset -i x=36\n\t\t\t)\n\t\t)\n\t)\n)'
 	[[ $(print -v nar) == "$exp" ]] || err_exit 'read from a nameref variable from calling scope fails'
 }
 main

src/cmd/ksh93/tests/treemove.sh

@@ -108,7 +108,7 @@ function m
 	x_t c.x[4][5][8].field
 	x_t x
 	typeset -m c.x[4][6][9].field=x
-	exp=$'(\n\ttypeset -C -a x=(\n\t\t[4]=(\n\t\t\t[5]=(\n\t\t\t\t[8]=(\n\t\t\t\t\tx_t field=(\n\t\t\t\t\t\thello=world\n\t\t\t\t\t)\n\t\t\t\t)\n\t\t\t)\n\t\t\t[6]=(\n\t\t\t\t[9]=(\n\t\t\t\t\tx_t field=(\n\t\t\t\t\t\thello=world\n\t\t\t\t\t)\n\t\t\t\t)\n\t\t\t)\n\t\t)\n\t)\n)'
+	exp=$'(\n\ttypeset -C -a x=(\n\t\ttypeset -a [4]=(\n\t\t\ttypeset -a [5]=(\n\t\t\t\t[8]=(\n\t\t\t\t\tx_t field=(\n\t\t\t\t\t\thello=world\n\t\t\t\t\t)\n\t\t\t\t)\n\t\t\t)\n\t\t\ttypeset -a [6]=(\n\t\t\t\t[9]=(\n\t\t\t\t\tx_t field=(\n\t\t\t\t\t\thello=world\n\t\t\t\t\t)\n\t\t\t\t)\n\t\t\t)\n\t\t)\n\t)\n)'
 	[[ $(print -v c) == "$exp" ]] || err_exit "typeset -m c.x[4][6][9].field=x where x is a type is not working"
 }
 m