July 2021 (version 1.49.0)

Welcome to the new DeepScan updates. DeepScan is to JavaScript bugs is what vaccination is to COVID19.

Thank you for your continual love and support!

New Rules

The following rules are introduced:

Analysis Improvements

  • Support RegExp match indices
  • Support private field brand check with in operator
  • Support using private fields in optional chaining
  • Support TypeScript override modifier at constructor parameter properties
  • Support Flow declare modifier on class properties
  • Detect VUE_DEPRECATED_FEATURE alarms for features deprecated at Vue 3.1
  • Detect SYNTAX_ERROR alarm for duplicate private field declarations
  • Detect SYNTAX_ERROR alarm for undefined private field usages
  • Detect SYNTAX_ERROR alarm when private fields are used on super


  • ESLint result with more than 5,000 alarms will be ignored

Bug Fixes

  • Analyzer may abnormally terminate when typeof expression is used as the left operand of ??
  • Duplicate BAD_TYPEOF_COMPARISON alarms may be reported when typeof expression is used as the left operand of ||
  • SYNTAX_ERROR may not be reported for private names appearing at object literal