From fbe835a91fb77f159fbc27adc56c1a020296c56b Mon Sep 17 00:00:00 2001
From: Michel Weststrate <mweststrate@gmail.com>
Date: Mon, 21 Jan 2019 09:55:51 +0100
Subject: [PATCH] Make sure isolateGlobalState is called first, fixes#1869

---
 src/api/configure.ts     | 6 +++---
 test/base/strict-mode.js | 9 +++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/api/configure.ts b/src/api/configure.ts
index 38647e61a..f01e7cd55 100644
--- a/src/api/configure.ts
+++ b/src/api/configure.ts
@@ -19,6 +19,9 @@ export function configure(options: {
         disableErrorBoundaries,
         reactionScheduler
     } = options
+    if (options.isolateGlobalState === true) {
+        isolateGlobalState()
+    }
     if (enforceActions !== undefined) {
         if (typeof enforceActions === "boolean" || enforceActions === "strict")
             deprecated(
@@ -49,9 +52,6 @@ export function configure(options: {
     if (computedRequiresReaction !== undefined) {
         globalState.computedRequiresReaction = !!computedRequiresReaction
     }
-    if (options.isolateGlobalState === true) {
-        isolateGlobalState()
-    }
     if (disableErrorBoundaries !== undefined) {
         if (disableErrorBoundaries === true)
             console.warn(
diff --git a/test/base/strict-mode.js b/test/base/strict-mode.js
index 11b4c1a13..50394c4c0 100644
--- a/test/base/strict-mode.js
+++ b/test/base/strict-mode.js
@@ -240,3 +240,12 @@ test("warn on unsafe reads", function() {
         mobx.configure({ computedRequiresReaction: false })
     }
 })
+
+test("#1869", function() {
+    const x = mobx.observable.box(3)
+    mobx.configure({ enforceActions: "always", isolateGlobalState: true })
+    expect(() => {
+        x.set(4)
+    }).toThrow("Since strict-mode is enabled")
+    mobx._resetGlobalState() // should preserve strict mode
+})