Michael Feathers michaelfeathers

michaelfeathers / gist:1855765

Created February 17, 2012 22:19

Five lines that turn Ruby into a different language

	class Object
	def method_missing m, *args
	Object.respond_to?(m, true) ? Object.send(m, self, *args) : super
	end
	end

michaelfeathers / gist:2413318

Created April 18, 2012 12:34

Each versus Reduce

michaelfeathers / gist:2572083

Created May 1, 2012 22:44

Better

	import Data.List

	lineBreak :: String -> String
	lineBreak = joinBrokenLines . joinWordsInBrokenLines . brokenLines . words

	brokenLines :: [String] -> [[String]]
	brokenLines [] = []
	brokenLines wordList = brokenLine : brokenLines remainingWords
	where (brokenLine, remainingWords) = splitAt (brokenLineWordCount wordList) wordList

michaelfeathers / gist:3827233

Created October 3, 2012 14:33

Code volume

	# A poor man's complexity measure for a file or group of files
	puts ARGF.lines.grep(/^([ \t]*)/) { $1 }.map(&:length).reduce(0, :+)

michaelfeathers / gist:3832740

Created October 4, 2012 10:19

Descending sort of Ruby files in a repository by number of commits

git log --name-only --no-merges | grep \.rb$ | sort | uniq -c | sort -nr

michaelfeathers / gist:3837149

Created October 4, 2012 23:39

Turbulence Light - generates a turbulence dataset for a Ruby git repository


	def complexity filename
	File.read(filename).lines.grep(/^([ \t]*)/) { $1 }.map(&:length).reduce(0, :+)
	end

	commit_filenames = `git log --name-only \| grep \.rb$`.lines \
	.map(&:strip) \
	.reject { \|fn\| fn.include? "_spec" } \
	.reject { \|fn\| fn.include? "vendor" }

michaelfeathers / gist:3838607

Created October 5, 2012 07:45

Turbulence Light-er


	def complexity filename
	File.read(filename).lines.grep(/^([ \t]*)/) { $1 }.map(&:length).reduce(0, :+)
	end

	filenames = `git log --name-only \| grep \.rb$`.lines \
	.map(&:strip) \
	.reject { \|fn\| fn.include? "_spec" } \
	.reject { \|fn\| fn.include? "vendor" }

michaelfeathers / gist:4062900

Created November 12, 2012 23:54

	require 'ostruct'
	require 'date'

	class OrdersReport < Struct.new(:orders,:date_range)
	def total_sales_within_date_range
	orders.select {\|order\| date_range.include?(order.placed_at) }
	.map(&:amount)
	.reduce(0.0,:+)
	end
	end

michaelfeathers / gist:4185398

Created December 1, 2012 21:55

Sometimes you just need to zip two hashes

	def zip_hash hash_a, hash_b, missing_element = nil
	all_keys = (hash_a.keys + hash_b.keys).uniq
	result = {}
	all_keys.each do \|key\|
	result[key] = [hash_a[key] \|\| missing_element, hash_b[key] \|\| missing_element]
	end
	result
	end

michaelfeathers / gist:4203595

Created December 4, 2012 12:59

	# :: [[a,b]] -> (a..a) -> b -> [[a,b]]]
	def spread mappings, range, default_value = 0
	occupied = Hash[mappings]
	range.map { \|index\| [index, occupied[index] \|\| default_value] }
	end