From d87223741448e0ad851949aafce5bd0441b8b9ab Mon Sep 17 00:00:00 2001
From: Mark Wooding <mdw@distorted.org.uk>
Date: Sat, 30 Jun 2018 22:45:49 +0100
Subject: [PATCH] dep.js: Fix the way `STATE' is handled.

Use the correct global `STATE' variable throughout, rather than
sometimes using a per-object `state' slot; restore it properly after
changing it; and actually set the `frozen' state in `with_frozen'.

How did this ever work?
---
 dep.js | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/dep.js b/dep.js
index d5235be..d21f94a 100644
--- a/dep.js
+++ b/dep.js
@@ -255,7 +255,7 @@ Dep.prototype = {
      * If the receiver isn't up-to-date then we synthesize the flags.
      */
 
-    if (this.state === 'ready') return F_VALUE | F_DEPS;
+    if (STATE === 'ready') return F_VALUE | F_DEPS;
     else if (this._generation === GENERATION) return this.__flags;
     else if (this._value_function === null) return F_VALUE | F_DEPS;
     else return 0;
@@ -394,7 +394,7 @@ Dep.prototype = {
 
     var val;
 
-    if (state === 'recomputing') {
+    if (STATE === 'recomputing') {
       if (EVALUATING) {
 	this._dependents[EVALUATING._seq] = EVALUATING;
 	EVALUATING._dependencies[this._seq] = this;
@@ -469,8 +469,8 @@ function recompute_pending() {
    */
 
   var d, f;
-
-  state = 'recomputing';
+  var old_state = STATE;
+  STATE = 'recomputing';
   try_finally(function () {
     while (PENDING.length) {
       d = PENDING.shift();
@@ -488,6 +488,7 @@ function recompute_pending() {
       d = PENDING.shift();
       d._value = BAD;
     }
+    STATE = old_state;
   });
 }
 
@@ -503,7 +504,7 @@ function with_frozen(body, delay) {
    */
 
   var op, val;
-  var old_delayed, old_pending;
+  var old_delayed, old_pending, old_state;
 
   switch (STATE) {
   case 'frozen':
@@ -516,6 +517,8 @@ function with_frozen(body, delay) {
   case 'ready':
     old_delayed = DELAYED;
     old_pending = PENDING;
+    old_state = STATE;
+    STATE = "frozen";
     try_finally(function () {
       DELAYED = [];
       PENDING = [];
@@ -530,6 +533,7 @@ function with_frozen(body, delay) {
     }, function () {
       DELAYED = old_delayed;
       PENDING = old_pending;
+      STATE = old_state;
     });
     break;
   }
-- 
2.11.0