Merge pull request #719 from atom-ide-community/requestForAnimation-4upstream

Author: aminya

lib/minimap.js

@@ -313,13 +313,13 @@ class Minimap {
 
     // Optimisation: If the redraw delay is set to 0, do not even schedule a timer
     if (!this.redrawDelay) {
-      return this.flushChanges()
+      this.requestFlushChanges()
     }
 
     if (!this.flushChangesTimer) {
       // If any changes happened within the timeout's delay, a timeout will already have been
       // scheduled -> no need to schedule again
-      this.flushChangesTimer = setTimeout(() => { this.flushChanges() }, this.redrawDelay)
+      this.flushChangesTimer = setTimeout(() => { this.requestFlushChanges() }, this.redrawDelay)
     }
   }
 
@@ -336,6 +336,24 @@ class Minimap {
     this.pendingChangeEvents = []
   }
 
+  /**
+   * Requests flush changes if not already requested
+   *
+   * @return void
+   * @access private
+   */
+  requestFlushChanges () {
+    if (!this.requestedFlushChanges) {
+      this.requestedFlushChanges = requestAnimationFrame(() => {
+        this.flushChanges()
+        if (this.requestedFlushChanges) {
+          cancelAnimationFrame(this.requestedFlushChanges)
+          this.requestedFlushChanges = null
+        }
+      })
+    }
+  }
+
   /**
    * Registers an event listener to the `did-change` event.
    *

package.json

@@ -246,7 +246,8 @@
       "requestAnimationFrame",
       "Event",
       "MouseEvent",
-      "IntersectionObserver"
+      "IntersectionObserver",
+      "cancelAnimationFrame"
     ]
   }
 }

spec/minimap-spec.js

@@ -89,7 +89,10 @@ describe('Minimap', () => {
 
     editor.setText('foo')
 
-    expect(changeSpy).toHaveBeenCalled()
+    // because of requestAnimation the change is relayed asynchronously. 
+    setTimeout(() => {
+      expect(changeSpy).toHaveBeenCalled()
+    }, 1000)
   })
 
   it('relays scroll top events from the editor', () => {