File Metrics for Kotlin

This document outlines the definition of file metrics for Kotlin.

complexity

The "complexity" metric counts:

if and else if statements
elvis expression ?:
for, while and do...while loops
branches (not else branch) in the when statements/expressions
catch labels in try-catch statements
logical binary operations && and ||
everything counted for the "functions" metric

It does not count:

.forEach(...) method call for iterables and other of built-in function calls

functions

The "functions" metric counts:

lambda expressions and anonymous functions
init blocks
secondary constructors
getters and setters
functional interface ( this happens due to a bug from Kotlin parser )

It does not count:

primary constructor
inline value class with syntax value class ...

classes

The "classes" metric counts:

definitions of class, abstract class, interface and enum
object expressions/declarations with the keyword object and companion object

It does not count:

inline classes
functional interface

lines_of_code, comment_lines, real_lines_of_code and keywords_in_comments