fix: split components under preserved root resetting ___isPreserved (#…

…1559)

(cherry picked from commit 03bb099)

packages/marko/src/runtime/components/beginComponent.js

@@ -45,10 +45,10 @@ module.exports = function beginComponent(
   let runtimeId = out.global.runtimeId;
 
   componentDef.___renderBoundary = true;
+  componentDef.___parentPreserved = componentsContext.___isPreserved;
 
   if (isSplitComponent === false && out.global.noBrowserRerender !== true) {
     componentDef.___flags |= FLAG_WILL_RERENDER_IN_BROWSER;
-    componentDef.___parentPreserved = componentsContext.___isPreserved;
     componentsContext.___isPreserved = false;
   }
 

packages/marko/test/components-browser/fixtures/component-preserve-multiple-split/components/app-split/component-browser.js

@@ -0,0 +1,7 @@
+window.mountCount = 0;
+
+module.exports = {
+  onMount: function() {
+    window.mountCount++;
+  }
+};

packages/marko/test/components-browser/fixtures/component-preserve-multiple-split/components/app-split/index.marko

@@ -0,0 +1 @@
+<div/>

packages/marko/test/components-browser/fixtures/component-preserve-multiple-split/index.marko

@@ -0,0 +1,7 @@
+class {}
+
+<div no-update>
+    <app-split/>
+    <app-split/>
+    <app-split/>
+</div>

packages/marko/test/components-browser/fixtures/component-preserve-multiple-split/test.js

@@ -0,0 +1,6 @@
+var expect = require("chai").expect;
+
+module.exports = function(helpers) {
+  helpers.mount(require.resolve("./index"), {});
+  expect(window.mountCount).to.equal(3);
+};