add-zle-hook-widget and multiple hooks

[Daniel Shahaf <d.s@xxxxxxxxxxxxxxxxxx>]

When two or more zle-line-pre-redraw hooks are registered using
add-zle-hook-widget, the value of $LASTWIDGET when the each hook is
called is the name of the former hook:

    [Eric Freese wrote in https://github.com/zsh-users/zsh-autosuggestions/issues/529#issuecomment-632113840]
    $ zsh -df
    % autoload add-zle-hook-widget
    % f() {}
    % g() { zle -M "$(typeset -p LASTWIDGET)" }
    % add-zle-hook-widget line-pre-redraw f
    % add-zle-hook-widget line-pre-redraw g
    % x<CURSOR>
    typeset -r LASTWIDGET=f

The issue here is that g would like to to know what widget was invoked
immediately before the redraw.  In the example, that'd be self-insert.

I've attached two proofs of concept.  WDYT?

I'll add docs, etc, once an approach is chosen.

Cheers,

Daniel

P.S.  For the latter patch, note that «zle $widget -f» is distinct from
«zle -f».

diff --git a/Functions/Misc/add-zle-hook-widget b/Functions/Misc/add-zle-hook-widget
index 9cc35496f..f5f9b615d 100644
--- a/Functions/Misc/add-zle-hook-widget
+++ b/Functions/Misc/add-zle-hook-widget
@@ -41,6 +41,7 @@ zstyle zle-hook types ${hooktypes#zle-}
 function azhw:${^hooktypes} {
     local -a hook_widgets
     local hook
+    readonly LAST_NONHOOK_WIDGET=$LASTWIDGET
     # Values of these styles look like number:name
     # and we run them in number order
     zstyle -a $WIDGET widgets hook_widgets

diff --git a/Functions/Misc/add-zle-hook-widget b/Functions/Misc/add-zle-hook-widget
index 9cc35496f..4d8049083 100644
--- a/Functions/Misc/add-zle-hook-widget
+++ b/Functions/Misc/add-zle-hook-widget
@@ -47,9 +47,9 @@ function azhw:${^hooktypes} {
     for hook in "${(@)${(@on)hook_widgets[@]}#<->:}"; do
 	if [[ "$hook" = user:* ]]; then
 	    # Preserve $WIDGET within the renamed widget
-	    zle "$hook" -N -- "$@"
+	    zle "$hook" -f "nolast" -N -- "$@"
 	else
-	    zle "$hook" -Nw -- "$@"
+	    zle "$hook" -f "nolast" -Nw -- "$@"
 	fi || return
     done
     return 0
diff --git a/Src/Zle/zle_thingy.c b/Src/Zle/zle_thingy.c
index ce61db27b..7604d5251 100644
--- a/Src/Zle/zle_thingy.c
+++ b/Src/Zle/zle_thingy.c
@@ -678,6 +678,7 @@ bin_zle_flags(char *name, char **args, UNUSED(Options ops), UNUSED(char func))
 		else if (!strcmp(*flag, "keepsuffix"))
 		    w->flags |= ZLE_KEEPSUFFIX;
 		*/
+		/* "nolast" is used in bin_zle_call */
 	        else if (!strcmp(*flag, "vichange")) {
 		    if (invicmdmode()) {
 			startvichange(-1);
@@ -703,7 +704,7 @@ bin_zle_call(char *name, char **args, UNUSED(Options ops), UNUSED(char func))
 {
     Thingy t;
     struct modifier modsave = zmod;
-    int ret, saveflag = 0, setbindk = 0, setlbindk, remetafy;
+    int ret, saveflag = 0, setbindk = 0, setlbindk = 0, remetafy;
     char *wname = *args++, *keymap_restore = NULL, *keymap_tmp;
 
     if (!wname)
@@ -727,12 +728,23 @@ bin_zle_call(char *name, char **args, UNUSED(Options ops), UNUSED(char func))
     while (*args && **args == '-') {
 	char skip_this_arg[2] = "x";
 	char *num;
+	char *flag;
 	if (!args[0][1] || args[0][1] == '-') {
 	    args++;
 	    break;
 	}
 	while (*++(*args)) {
 	    switch (**args) {
+	    case 'f':
+		flag = args[0][1] ? args[0]+1 : args[1];
+		if (strcmp(flag, "nolast")) {
+		    zwarnnam(name, "%s", "'nolast' expected after -f");
+		    if (remetafy)
+			metafy_line();
+		    return 1;
+		}
+		setlbindk = 1;
+		break;
 	    case 'n':
 		num = args[0][1] ? args[0]+1 : args[1];
 		if (!num) {
@@ -787,7 +799,7 @@ bin_zle_call(char *name, char **args, UNUSED(Options ops), UNUSED(char func))
      * a vi range to detect a repeated key */
     setbindk = setbindk ||
 	(t->widget && (t->widget->flags & (WIDGET_INT | ZLE_VIOPER)) == WIDGET_INT);
-    setlbindk = t->widget && (t->widget->flags & ZLE_NOLAST) == ZLE_NOLAST;
+    setlbindk |= t->widget && (t->widget->flags & ZLE_NOLAST) == ZLE_NOLAST;
     ret = execzlefunc(t, args, setbindk, setlbindk);
     unrefthingy(t);
     if (saveflag)