25831: fix empty return values from subscript matches with RC_EXPAND_PARAM

2 files changed, 24 insertions, 15 deletions

diff --git a/Src/params.c b/Src/params.c
index 65b3ecff8..71cb2a907 100644
--- a/Src/params.c
+++ b/Src/params.c
@@ -1810,11 +1810,10 @@ fetchvalue(Value v, char **pptr, int bracks, int flags)
 	    /* Overload v->isarr as the flag bits for hashed arrays. */
 	    v->isarr = flags | (isvarat ? SCANPM_ISVAR_AT : 0);
 	    /* If no flags were passed, we need something to represent *
-	     * `true' yet differ from an explicit WANTVALS.  This is a *
-	     * bit of a hack, but makes some sense:  When no subscript *
-	     * is provided, all values are substituted.                */
+	     * `true' yet differ from an explicit WANTVALS.  Use a     *
+	     * special flag for this case.                             */
 	    if (!v->isarr)
-		v->isarr = SCANPM_MATCHMANY;
+		v->isarr = SCANPM_ARRONLY;
 	}
 	v->pm = pm;
 	v->flags = 0;
@@ -2188,7 +2187,8 @@ setstrvalue(Value v, char *val)
 	zsfree(val);
 	return;
     }
-    if ((v->pm->node.flags & PM_HASHED) && (v->isarr & SCANPM_MATCHMANY)) {
+    if ((v->pm->node.flags & PM_HASHED) &&
+	(v->isarr & (SCANPM_MATCHMANY|SCANPM_ARRONLY))) {
 	zerr("%s: attempt to set slice of associative array", v->pm->node.nam);
 	zsfree(val);
 	return;
diff --git a/Src/zsh.h b/Src/zsh.h
index 2ceab1dca..94d4503e4 100644
--- a/Src/zsh.h
+++ b/Src/zsh.h
@@ -1532,16 +1532,25 @@ struct tieddata {
 #define TYPESET_OPTNUM "LRZiEF"
 
 /* Flags for extracting elements of arrays and associative arrays */
-#define SCANPM_WANTVALS   (1<<0)
-#define SCANPM_WANTKEYS   (1<<1)
-#define SCANPM_WANTINDEX  (1<<2)
-#define SCANPM_MATCHKEY   (1<<3)
-#define SCANPM_MATCHVAL   (1<<4)
-#define SCANPM_MATCHMANY  (1<<5)
-#define SCANPM_ASSIGNING  (1<<6)
-#define SCANPM_KEYMATCH   (1<<7)
-#define SCANPM_DQUOTED    (1<<8)
-#define SCANPM_ISVAR_AT   ((-1)<<15)	/* Only sign bit is significant */
+#define SCANPM_WANTVALS   (1<<0) /* Return value includes hash values */
+#define SCANPM_WANTKEYS   (1<<1) /* Return value includes hash keys */
+#define SCANPM_WANTINDEX  (1<<2) /* Return value includes array index */
+#define SCANPM_MATCHKEY   (1<<3) /* Subscript matched against key */
+#define SCANPM_MATCHVAL   (1<<4) /* Subscript matched against value */
+#define SCANPM_MATCHMANY  (1<<5) /* Subscript matched repeatedly, return all */
+#define SCANPM_ASSIGNING  (1<<6) /* Assigning whole array/hash */
+#define SCANPM_KEYMATCH   (1<<7) /* keys of hash treated as patterns */
+#define SCANPM_DQUOTED    (1<<8) /* substitution was double-quoted
+				  * (only used for testing early end of
+				  * subscript)
+				  */
+#define SCANPM_ARRONLY    (1<<9) /* value is array but we don't
+				  * necessarily want to match multiple
+				  * elements
+				  */
+#define SCANPM_ISVAR_AT   ((-1)<<15)	/* "$foo[@]"-style substitution
+					 * Only sign bit is significant
+					 */
 
 /*
  * Flags for doing matches inside parameter substitutions, i.e.