webgl: Check shader compilation status on use_program.

1 files changed, 12 insertions, 1 deletions

diff --git a/components/script/dom/webglprogram.rs b/components/script/dom/webglprogram.rs
index 272eeae72aa..42eb0a23581 100644
--- a/components/script/dom/webglprogram.rs
+++ b/components/script/dom/webglprogram.rs
@@ -73,8 +73,19 @@ impl WebGLProgram {
     }
 
     /// glUseProgram
-    pub fn use_program(&self) {
+    pub fn use_program(&self) -> WebGLResult<()> {
+        match self.fragment_shader.get() {
+            Some(ref shader) if shader.successfully_compiled() => {},
+            _ => return Err(WebGLError::InvalidOperation),
+        }
+
+        match self.vertex_shader.get() {
+            Some(ref shader) if shader.successfully_compiled() => {},
+            _ => return Err(WebGLError::InvalidOperation),
+        }
+
         self.renderer.send(CanvasMsg::WebGL(CanvasWebGLMsg::UseProgram(self.id))).unwrap();
+        Ok(())
     }
 
     /// glAttachShader