From: Jean Privat <jean@pryen.org>
Date: Mon, 28 Sep 2015 14:35:40 +0000 (-0400)
Subject: Merge: Fixes for ordered trees
X-Git-Tag: v0.7.8~5
X-Git-Url: http://nitlanguage.org?hp=7b076a95018b6d2e9c76963d832c8830f7e6087e

Merge: Fixes for ordered trees

Some fixes related of the last changes

Pull-Request: #1741
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>
---

diff --git a/lib/ordered_tree.nit b/lib/ordered_tree.nit
index 0b1d383..d1dde15 100644
--- a/lib/ordered_tree.nit
+++ b/lib/ordered_tree.nit
@@ -128,7 +128,15 @@ class OrderedTree[E: Object]
 	do
 		var old_parent = parents.get_or_null(e)
 		if old_parent != null then
-			sub[old_parent].remove(e)
+			var subs = sub[old_parent]
+			subs.remove(e)
+			if subs.is_empty then
+				# remove the sub when all children are detached
+				# so that `==` and `hash` are sane
+				# Otherwise an empty array will be considered
+				# differently than no array.
+				sub.keys.remove(old_parent)
+			end
 		else if roots.has(e) then
 			roots.remove(e)
 		end
@@ -149,6 +157,7 @@ class OrderedTree[E: Object]
 	do
 		if not sub.has_key(e) then return
 		var subs = sub[e]
+		if subs.is_empty then return
 		var last = subs.last
 		for e2 in subs do
 			if e2 != last then