41828, 41830: skip SHFILEEXPANSION for new nodes added by stringsubst() in prefork()

ChangeLog

@@ -1,3 +1,10 @@
+2017-10-08  Barton E. Schaefer  <schaefer@zsh.org>
+
+	* 41830: Test/E01options.ztst: test for 41828.
+
+	* 41828: Src/subst.c: skip SHFILEEXPANSION for new nodes added
+	by stringsubst() in prefork().
+
 2017-10-07  Oliver Kiddle  <opk@zsh.org>
 
 	* 41827: Completion/Zsh/Context/_brace_parameter: correct

Src/subst.c

@@ -106,15 +106,20 @@ prefork(LinkList list, int flags, int *ret_flags)
 	ret_flags = &ret_flags_local; /* will be discarded */
 
     queue_signals();
-    for (node = firstnode(list); node; incnode(node)) {
+    node = firstnode(list);
+    while (node) {
+	LinkNode nextnode = 0;
 	if ((flags & (PREFORK_SINGLE|PREFORK_ASSIGN)) == PREFORK_ASSIGN &&
 	    (insnode = keyvalpairelement(list, node))) {
 	    node = insnode;
+	    incnode(node);
 	    *ret_flags |= PREFORK_KEY_VALUE;
 	    continue;
 	}
-	if (errflag)
+	if (errflag) {
+	    unqueue_signals();
 	    return;
+	}
 	if (isset(SHFILEEXPANSION)) {
 	    /*
 	     * Here and below we avoid taking the address
@@ -132,6 +137,12 @@ prefork(LinkList list, int flags, int *ret_flags)
 	     * testing if cptr changed...
 	     */
 	    setdata(node, cptr);
+	    /*
+	     * Advance now because we must not expand filenames again
+	     * after string substitution (which may insert new nodes).
+	     */
+	    nextnode = node;
+	    incnode(nextnode);
 	}
 	if (!(node = stringsubst(list, node,
 				 flags & ~(PREFORK_TYPESET|PREFORK_ASSIGN),
@@ -139,6 +150,10 @@ prefork(LinkList list, int flags, int *ret_flags)
 	    unqueue_signals();
 	    return;
 	}
+	if (isset(SHFILEEXPANSION))
+	    node = nextnode;
+	else
+	    incnode(node);
     }
     for (node = firstnode(list); node; incnode(node)) {
 	if (node == stop)

Test/E01options.ztst

@@ -1026,6 +1026,18 @@
 >$lspath $lspath =
 >$lspath
 
+  () {
+    emulate -L sh
+    v='~/one ~/two'
+    print -l -- $v $v
+  }
+0:SH_FILE_EXPANSION option with GLOB_SUBST et al.
+F:Regression test for workers/41811
+>~/one
+>~/two
+>~/one
+>~/two
+
   testpat() {
     if [[ $1 = ${~2} ]]; then print $1 $2 yes; else print $1 $2 no; fi
   }