Module: SimpleCov::Combine::LinesCombiner

Defined in:
lib/simplecov/combine/lines_combiner.rb

Overview

Combine two different lines coverage results on same file

Should be called through ‘SimpleCov.combine`.

Class Method Summary collapse

Class Method Details

.combine(coverage_a, coverage_b) ⇒ Object

Build a fresh array sized to the longer input. The previous implementation mutated whichever input was longer in place, which could surprise callers holding a reference to that array (e.g. the parsed ‘coverage` key of a resultset hash being passed into a second merge).



17
18
19
20
 
# File 'lib/simplecov/combine/lines_combiner.rb', line 17

def combine(coverage_a, coverage_b)
  size = [coverage_a.size, coverage_b.size].max
  Array.new(size) { |i| merge_line_coverage(coverage_a[i], coverage_b[i]) }
end

.merge_line_coverage(first_val, second_val) ⇒ Integer || nil

Two runs of the same source file should agree on which lines are coverage-relevant (‘nil` for comments / whitespace, `0`+ for executable). When they don’t, treat “relevant on either side” as relevant rather than masking a real ‘0` as `nil`, which would silently drop an uncovered line from the denominator and inflate the percentage.

Logic:

> nil + nil = nil

> nil + int = int (preserves a relevant-but-uncovered 0)

> int + int = int (sum)

Parameters:

  • first_val (Integer || nil)
  • second_val (Integer || nil)

Returns:

  • (Integer || nil) 


38
39
40
41
42
 
# File 'lib/simplecov/combine/lines_combiner.rb', line 38

def merge_line_coverage(first_val, second_val)
  return nil if first_val.nil? && second_val.nil?

  first_val.to_i + second_val.to_i
end