Some of the Kotlin keywords are valid identifiers in Java, for example: in, object, is. If a Java library uses a Kotlin keyword for a method, you can still call the method escaping it with the backtick character (`), for example, foo.`is`(bar). Sometimes this escaping is redundant and can be safely omitted. The inspection discovers and reports such cases and is paired with the 'Remove redundant backticks' quick-fix, which allows you to amend the highlighted code.

Examples:

  fun `is`(x: String) {}
  fun foo() {
      `is`("bar") // 'is' is a keyword, backticks are required
  }

  fun `test that smth works as designed`() {} // OK, complex identifier for readability improvement

  val `a` = 1  // no need for backticks