Since 2015, the JavaScript language has rapidly evolved with a yearly release cadence and open development process. As a result, it makes the gap between the language specification written in English and tools, such as parsers, interpreters, and static analyzers. Therefore, language designers and tool developers for JavaScript suffer from manually filling the gap between them. JISET and its extensions lessen the burden by automatically extracting a mechanized specification from the language specification for JavaScript.


In this tutorial, we introduce three tools in the JISET family and demonstrate how they fill the gap between the language specification and tools:

We explain how to extract a mechanized specification from the language specification using JISET, a JavaScript IR-based Semantics Extraction Toolchain.

We explain how to synthesize conformance test programs and detect conformance bugs in both JavaScript engines and specifications using JEST, a JavaScript Engine and Specification Tester.

We explain how to analyze specification types and detect type-related bugs in the language specification using JSTAR, a JavaScript Specification Type Analyzer with Refinement.