Tests generation of synthetic and real GL errors On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS getError was expected value: NO_ERROR : Testing getActiveAttrib PASS context.getActiveAttrib(null, 2) is null PASS getError was expected value: INVALID_VALUE : PASS getError was expected value: NO_ERROR : PASS context.getActiveAttrib(program, 2) is null PASS getError was expected value: INVALID_VALUE : PASS getError was expected value: NO_ERROR : Testing getActiveUniform PASS context.getActiveUniform(null, 0) is null PASS getError was expected value: INVALID_VALUE : PASS getError was expected value: NO_ERROR : PASS context.getActiveUniform(program, 50) is null PASS getError was expected value: INVALID_VALUE : PASS getError was expected value: NO_ERROR : Testing attempts to manipulate the default framebuffer PASS context.bindFramebuffer(context.FRAMEBUFFER, null) is undefined. PASS getError was expected value: NO_ERROR : PASS context.framebufferRenderbuffer(context.FRAMEBUFFER, context.DEPTH_ATTACHMENT, context.RENDERBUFFER, null) is undefined. PASS getError was expected value: INVALID_OPERATION : PASS getError was expected value: NO_ERROR : PASS context.framebufferTexture2D(context.FRAMEBUFFER, context.COLOR_ATTACHMENT0, context.TEXTURE_2D, null, 0) is undefined. PASS getError was expected value: INVALID_OPERATION : PASS getError was expected value: NO_ERROR : PASS successfullyParsed is true TEST COMPLETE