Test of drawArrays with out-of-bounds parameters On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". Test empty buffer PASS context.drawArrays(context.TRIANGLES, 0, 10000) generated expected GL error: INVALID_OPERATION. PASS context.drawArrays(context.TRIANGLES, 0, -1) generated expected GL error: INVALID_VALUE. PASS context.drawArrays(context.TRIANGLES, -1, 0) generated expected GL error: INVALID_VALUE. PASS context.drawArrays(context.TRIANGLES, 0, 0) generated expected GL error: NO_ERROR. PASS context.drawArrays(context.TRIANGLES, 100, 0) generated expected GL error: NO_ERROR. Test buffer with 3 float vectors PASS context.checkFramebufferStatus(context.FRAMEBUFFER) is context.FRAMEBUFFER_COMPLETE PASS context.drawArrays(context.TRIANGLES, 0, 3) is undefined PASS context.drawArrays(context.TRIANGLES, 0, 3) generated expected GL error: NO_ERROR. PASS context.drawArrays(0x0009, 0, 3) generated expected GL error: INVALID_ENUM. PASS context.drawArrays(context.TRIANGLES, 3, 2) generated expected GL error: INVALID_OPERATION. PASS context.drawArrays(context.TRIANGLES, 0, 10000) generated expected GL error: INVALID_OPERATION. PASS context.drawArrays(context.TRIANGLES, 0, -1) generated expected GL error: INVALID_VALUE. PASS context.drawArrays(context.TRIANGLES, -1, 0) generated expected GL error: INVALID_VALUE. PASS context.drawArrays(context.TRIANGLES, 0, 0) generated expected GL error: NO_ERROR. PASS context.drawArrays(context.TRIANGLES, 100, 0) generated expected GL error: NO_ERROR. PASS successfullyParsed is true TEST COMPLETE