30041: fix bash-style offsets for positional parameters when scalars

2 files changed, 23 insertions, 16 deletions

diff --git a/ChangeLog b/ChangeLog
index 4298f83d0..52e672f88 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2011-12-21  Peter Stephenson  <p.w.stephenson@ntlworld.com>
 
+	* 30041: Src/subst.c: the offset hack to make
+	${foo:offset:length} bash compatible with positional parameters
+	doesn't apply when we're indexing into characters of one
+	positional parameter.
+
 	* T.C. Hollingsworth: 30036: Completion/Unix/Command/_systemctl:
 	new arguments.
 
@@ -15786,5 +15791,5 @@
 
 *****************************************************
 * This is used by the shell to define $ZSH_PATCHLEVEL
-* $Revision: 1.5547 $
+* $Revision: 1.5548 $
 *****************************************************
diff --git a/Src/subst.c b/Src/subst.c
index 4e8ed721d..ea6bf3af2 100644
--- a/Src/subst.c
+++ b/Src/subst.c
@@ -2878,24 +2878,26 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int ssub)
 			    return NULL;
 		    }
 		}
-		if (horrible_offset_hack) {
-		    /*
-		     * As part of the 'orrible hoffset 'ack,
-		     * (what hare you? Han 'orrible hoffset 'ack,
-		     * sergeant major), if we are given a ksh/bash/POSIX
-		     * style positional parameter array which includes
-		     * offset 0, we use $0.
-		     */
-		    if (offset == 0 && isarr) {
-			offset_hack_argzero = 1;
-		    } else if (offset > 0) {
-			offset--;
-		    }
-		}
 		if (isarr) {
-		    int alen = arrlen(aval), count;
+		    int alen, count;
 		    char **srcptr, **dstptr, **newarr;
 
+		    if (horrible_offset_hack) {
+			/*
+			 * As part of the 'orrible hoffset 'ack,
+			 * (what hare you? Han 'orrible hoffset 'ack,
+			 * sergeant major), if we are given a ksh/bash/POSIX
+			 * style positional parameter array which includes
+			 * offset 0, we use $0.
+			 */
+			if (offset == 0) {
+			    offset_hack_argzero = 1;
+			} else if (offset > 0) {
+			    offset--;
+			}
+		    }
+
+		    alen = arrlen(aval);
 		    if (offset < 0) {
 			offset += alen;
 			if (offset < 0)