From 86ed7a791581b76af8976bc82d0f7c7f6f3205c6 Mon Sep 17 00:00:00 2001
From: Michael Trotter <spicydonuts@users.noreply.github.com>
Date: Mon, 1 Oct 2018 12:17:18 -0600
Subject: [PATCH] Fix setStateThen's state arg (#56)

---
 bower.json                               |  3 ++-
 examples/component/src/ToggleButton.purs |  6 ++++--
 src/React/Basic.js                       | 14 +++++++++++---
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/bower.json b/bower.json
index dc054bb..182b0f3 100644
--- a/bower.json
+++ b/bower.json
@@ -23,6 +23,7 @@
     "purescript-exceptions": "^4.0.0"
   },
   "devDependencies": {
-    "purescript-web-html": "^1.0.0"
+    "purescript-web-html": "^1.0.0",
+    "purescript-console": "^4.1.0"
   }
 }
diff --git a/examples/component/src/ToggleButton.purs b/examples/component/src/ToggleButton.purs
index 852b44a..9b546bc 100644
--- a/examples/component/src/ToggleButton.purs
+++ b/examples/component/src/ToggleButton.purs
@@ -2,6 +2,7 @@ module ToggleButton where
 
 import Prelude
 
+import Effect.Console (log)
 import React.Basic as React
 import React.Basic.DOM as R
 import React.Basic.Events as Events
@@ -20,10 +21,11 @@ component = React.component { displayName: "ToggleButton", initialState, receive
     receiveProps _ =
       pure unit
 
-    render { props, state, setState } =
+    render { props, state, setStateThen } =
       R.button
         { onClick: Events.handler_ do
-            setState \s -> s { on = not s.on }
+            setStateThen (\s -> s { on = not s.on }) \nextState -> do
+              log $ "nextState: " <> show nextState
         , children:
             [ R.text props.label
             , R.text if state.on
diff --git a/src/React/Basic.js b/src/React/Basic.js
index 28ddad3..a2181c1 100644
--- a/src/React/Basic.js
+++ b/src/React/Basic.js
@@ -3,6 +3,14 @@
 var React = require("react");
 var Fragment = React.Fragment || "div";
 
+function setStateThen(instance) {
+  return function(update, then) {
+    return instance.setState(update, function() {
+      then(this.state);
+    });
+  };
+}
+
 exports.component_ = function(spec) {
   var Component = function constructor() {
     this.state = spec.initialState;
@@ -20,7 +28,7 @@ exports.component_ = function(spec) {
       props: this.props,
       state: this.state,
       setState: this._setState,
-      setStateThen: this._setState,
+      setStateThen: setStateThen(this),
       instance_: this
     });
   };
@@ -31,7 +39,7 @@ exports.component_ = function(spec) {
       props: this.props,
       state: this.state,
       setState: this._setState,
-      setStateThen: this._setState,
+      setStateThen: setStateThen(this),
       instance_: this
     });
   };
@@ -41,7 +49,7 @@ exports.component_ = function(spec) {
       props: this.props,
       state: this.state,
       setState: this._setState,
-      setStateThen: this._setState,
+      setStateThen: setStateThen(this),
       instance_: this
     });
   };