Support an 'owner' key in region_highlight.

This is to allow plugins to easily remove only entries they had added.
See zsh-users/zsh-syntax-highlighting#418 and
the cross-referenced issues.

Doc/Zsh/zle.yo

@@ -974,27 +974,30 @@ of the non-editable parts of the command line in tt(PREDISPLAY)
 and tt(POSTDISPLAY) are possible, but note that the tt(P) flag
 is needed for character indexing to include tt(PREDISPLAY).
 
-Each string consists of the following parts:
+Each string consists of the following whitespace-separated parts:
 
 startitemize()
 itemiz(Optionally, a `tt(P)' to signify that the start and end offset that
 follow include any string set by the tt(PREDISPLAY) special parameter;
 this is needed if the predisplay string itself is to be highlighted.
-Whitespace may follow the `tt(P)'.)
-itemiz(A start offset in the same units as tt(CURSOR), terminated by
-whitespace.)
-itemiz(An end offset in the same units as tt(CURSOR), terminated by
-whitespace.)
+Whitespace between the `tt(P)' and the start offset is optional.)
+itemiz(A start offset in the same units as tt(CURSOR).)
+itemiz(An end offset in the same units as tt(CURSOR).)
 itemiz(A highlight specification in the same format as
 used for contexts in the parameter tt(zle_highlight), see
 ifnzman(noderef(Character Highlighting))\
 ifzman(the section `Character Highlighting' below);
-for example, tt(standout) or tt(fg=red,bold)).
+for example, tt(standout) or tt(fg=red,bold).)
+itemiz(Optionally, a string of the form `tt(owner=)var(token)'.
+The var(token) value is preserved verbatim but not parsed in any way.
+Plugins may use this to identify elements they had added, for example, in order
+to remove them with
+`tt(region_highlight=+LPAR() ${region_highlight:#*owner=)var(token)tt(} +RPAR())'.)
 enditemize()
 
 For example, 
 
-example(region_highlight=("P0 20 bold"))
+example(region_highlight=("P0 20 bold owner=myplugin"))
 
 specifies that the first twenty characters of the text including
 any predisplay string should be highlighted in bold.

Src/Zle/zle.h

@@ -447,6 +447,10 @@ struct region_highlight {
      * Any of the flags defined above.
      */
     int flags;
+    /*
+     * User-settable "owner" key.  Metafied.
+     */
+    const char *owner;
 };
 
 /*

Src/Zle/zle_refresh.c

@@ -212,9 +212,9 @@ static zattr default_atr_on, special_atr_on;
 
 /*
  * Array of region highlights, no special termination.
- * The first element (0) always describes the region between
- * point and mark.  Any other elements are set by the user
- * via the parameter region_highlight.
+ * The first N_SPECIAL_HIGHLIGHTS elements describe special uses of
+ * highlighting, documented under N_SPECIAL_HIGHLIGHTS.
+ * Any other elements are set by the user via the parameter region_highlight.
  */
 
 /**/
@@ -414,16 +414,19 @@ get_region_highlight(UNUSED(Param pm))
 	 arrsize--;
 	 rhp++, arrp++) {
 	char digbuf1[DIGBUFSIZE], digbuf2[DIGBUFSIZE];
-	int atrlen = 0, alloclen;
+	int atrlen, alloclen;
+	const char owner_equals[] = "owner=";
 
 	sprintf(digbuf1, "%d", rhp->start);
 	sprintf(digbuf2, "%d", rhp->end);
 
 	atrlen = output_highlight(rhp->atr, NULL);
 	alloclen = atrlen + strlen(digbuf1) + strlen(digbuf2) +
-	    3; /* 2 spaces, 1 0 */
+	    3; /* 2 spaces, 1 terminating NUL */
 	if (rhp->flags & ZRH_PREDISPLAY)
 	    alloclen += 2; /* "P " */
+	if (rhp->owner)
+	    alloclen += 1 /* space */ + strlen(owner_equals) + strlen(rhp->owner);
 	*arrp = (char *)zhalloc(alloclen * sizeof(char));
 	/*
 	 * On input we allow a space after the flags.
@@ -436,6 +439,12 @@ get_region_highlight(UNUSED(Param pm))
 		(rhp->flags & ZRH_PREDISPLAY) ? "P" : "",
 		digbuf1, digbuf2);
 	(void)output_highlight(rhp->atr, *arrp + strlen(*arrp));
+
+	if (rhp->owner) {
+	    strcat(*arrp, " ");
+	    strcat(*arrp, owner_equals);
+	    strcat(*arrp, rhp->owner);
+	}
     }
     *arrp = NULL;
     return retarr;
@@ -502,7 +511,15 @@ set_region_highlight(UNUSED(Param pm), char **aval)
 	while (inblank(*strp))
 	    strp++;
 
-	match_highlight(strp, &rhp->atr);
+	strp = (char*) match_highlight(strp, &rhp->atr);
+
+	while (inblank(*strp))
+	    strp++;
+
+	if (strpfx("owner=", strp))
+	    rhp->owner = ztrdup(strp + 6);
+	else
+	    rhp->owner = NULL;
     }
 
     freearray(av);

Src/Zle/zle_utils.c

@@ -632,6 +632,7 @@ zle_save_positions(void)
 	    newrhp->next = NULL;
 	    newrhp->atr = rhp->atr;
 	    newrhp->flags = rhp->flags;
+	    /* TODO: save rhp->owner here? */
 	    if (zlemetaline) {
 		newrhp->start = rhp->start_meta;
 		newrhp->end = rhp->end_meta;
@@ -694,6 +695,7 @@ zle_restore_positions(void)
 
 	    rhp->atr = oldrhp->atr;
 	    rhp->flags = oldrhp->flags;
+	    rhp->owner = NULL;
 	    if (zlemetaline) {
 		rhp->start_meta = oldrhp->start;
 		rhp->end_meta = oldrhp->end;

Src/prompt.c

@@ -1724,10 +1724,11 @@ match_colour(const char **teststrp, int is_fg, int colour)
 /*
  * Match a set of highlights in the given teststr.
  * Set *on_var to reflect the values found.
+ * Return a pointer to the first character not consumed.
  */
 
 /**/
-mod_export void
+mod_export const char *
 match_highlight(const char *teststr, zattr *on_var)
 {
     int found = 1;
@@ -1745,7 +1746,7 @@ match_highlight(const char *teststr, zattr *on_var)
 	    atr = match_colour(&teststr, is_fg, 0);
 	    if (*teststr == ',')
 		teststr++;
-	    else if (*teststr)
+	    else if (*teststr && *teststr != ' ')
 		break;
 	    found = 1;
 	    /* skip out of range colours but keep scanning attributes */
@@ -1758,7 +1759,7 @@ match_highlight(const char *teststr, zattr *on_var)
 
 		    if (*val == ',')
 			val++;
-		    else if (*val)
+		    else if (*val && *val != ' ')
 			break;
 
 		    *on_var |= hl->mask_on;
@@ -1769,6 +1770,8 @@ match_highlight(const char *teststr, zattr *on_var)
 	    }
 	}
     }
+
+    return teststr;
 }
 
 /*

Test/X04zlehighlight.ztst

@@ -94,6 +94,17 @@
 0:basic region_highlight with 8 colors
 >0m27m24mCDE|32|trueCDE|39|
 
+  zpty_start
+  zpty_input 'rh_widget() { region_highlight+=( "0 4 fg=green owner=someplugin" ); typeset -p region_highlight }'
+  zpty_input 'zle -N rh_widget'
+  zpty_input 'bindkey "\C-a" rh_widget'
+  zpty_enable_zle
+  zpty_input $'\C-a'
+  zpty_line
+  zpty_stop
+0:region_highlight owner information round trips
+>typeset -a region_highlight=( '0 4 fg=green owner=someplugin' )
+
   zpty_start
   zpty_input 'rh_widget() { BUFFER="true"; region_highlight+=( "0 4 fg=#040810" ); }'
   zpty_input 'zle -N rh_widget'