Browser Testing using Grammars and a Consensus Oracle

on YouTube ↗43m

" summary

Generates HTML/CSS from spec-derived EBNF, compiles those grammars into generators, and runs property-based tests that shrink failing cases to minimal examples. Decides failures by a consensus oracle: multiple browsers driven via WebDriver produce screenshots, OpenCV computes delta images and a squared-sum threshold flags disagreements. Configuration lets weights bias generation; examples report bytes before/after shrinking. Prototype finds real bugs (servo crash in headless mode) and flags both single-browser outliers and messy three-way disagreements.

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" chapters (4)

1. 0:00Start
2. 3:10BROWSER RENDERING
3. 7:45SIMPLE PBT EXAMPLE
4. 26:06TEST SYSTEM ARCHITECTURE

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