Unit test for line widget focus restoration

Author: Narciso Jaramillo

test/index.html

@@ -25,6 +25,15 @@
         font-weight: bold;
         white-space: pre;
       }
+      #testground {
+        visibility: hidden;
+      }
+      #testground.offscreen {
+        visibility: visible;
+        position: absolute;
+        left: -10000px;
+        top: -10000px;
+      }
       .CodeMirror { border: 1px solid black; }
     </style>
   </head>
@@ -39,7 +48,7 @@ <h1>CodeMirror: Test Suite</h1>
     <p id=status>Please enable JavaScript...</p>
     <div id=output></div>
 
-    <div style="visibility: hidden" id=testground></div>
+    <div id=testground></div>
 
     <script src="driver.js"></script>
     <script src="test.js"></script>

test/test.js

@@ -971,6 +971,22 @@ testCM("lineWidgets", function(cm) {
   eqPos(cm.getCursor(), {line: 1, ch: 1});
 });
 
+testCM("lineWidgetFocus", function(cm) {
+  var place = document.getElementById("testground");
+  place.className = "offscreen";
+  try {
+    addDoc(cm, 500, 10);
+    var node = document.createElement("input");
+    var widget = cm.addLineWidget(1, node);
+    node.focus();
+    eq(document.activeElement, node);
+    cm.replaceRange("new stuff", {line: 1, ch: 0});
+    eq(document.activeElement, node);
+  } finally {
+    place.className = "";
+  }
+});
+
 testCM("getLineNumber", function(cm) {
   addDoc(cm, 2, 20);
   var h1 = cm.getLineHandle(1);