1 files changed, 35 insertions, 0 deletions
diff --git a/dom/canvas/test/webgl-conf/checkout/conformance/offscreencanvas/context-lost-worker.js b/dom/canvas/test/webgl-conf/checkout/conformance/offscreencanvas/context-lost-worker.js
new file mode 100644
index 0000000000..75cd4b0045
--- /dev/null
+++ b/dom/canvas/test/webgl-conf/checkout/conformance/offscreencanvas/context-lost-worker.js
@@ -0,0 +1,35 @@
+/*
+Copyright (c) 2019 The Khronos Group Inc.
+Use of this source code is governed by an MIT-style license that can be
+found in the LICENSE.txt file.
+*/
+
+importScripts("../../js/tests/canvas-tests-utils.js");
+self.onmessage = function(e) {
+    canvas = new OffscreenCanvas(10, 10);
+    gl = canvas.getContext('webgl');
+
+    // call testValidContext() before checking for the extension, because this is where we check
+    // for the isContextLost() method, which we want to do regardless of the extension's presence.
+    if (!testValidContext())
+        self.postMessage("Test failed");
+
+    extension = gl.getExtension("WEBGL_lose_context");
+    // need an extension that exposes new API methods.
+    OES_vertex_array_object = gl.getExtension("OES_vertex_array_object");
+    if (extension == null || OES_vertex_array_object == null)
+        self.postMessage("Test failed");
+
+    // We need to initialize |uniformLocation| before losing context.
+    // Otherwise gl.getUniform() when context is lost will throw.
+    uniformLocation = gl.getUniformLocation(program, "tex");
+    extension.loseContext();
+
+    canvas.addEventListener("webglcontextlost", function() {
+        if (testLostContextWithoutRestore())
+            self.postMessage("Test passed");
+        else
+            self.postMessage("Test failed");
+    }, false);
+}
+