test_match's Introduction

RecursiveMatch

Module for matching

What difference between `Kernel.match?/2` and `RecursiveMatch.match_r/3`?

When you use Kernel.match?/2

can't use functions as pattern
can't match not strict equality (only ===, no ==)

RecursiveMatch.match_r/3 allows you:

use functions as patterns
match not strictly (with option strict: false)
ignore order of lists item (with option ignore_order: true)

What is for `assert_match/3` and `refute_match/3`?

It is same as assert RecursiveMatch.match_r, but with detailed fail message.
ExUnit has no special message for match_r/3 and even no special message for match?/2 is not detailed enough, it has no diff in fail message.

assert_match/3 provides diff in test fail message

Installation

If available in Hex, the package can be installed by adding test_match to your list of dependencies in mix.exs:

Requires elixir ~> 1.5

def deps do
  [
    {:test_match, "~> 2.0"}
  ]
end

Usage

defmodule YourModule do
  import RecursiveMatch

  def function1 do
    ...
  end
  
  def function2 do
    ...
    match_r 1, 2 
    match_r a, b
    match_r :_, b
    match_r function1(), 1
    match_r [1, 2], [2, 1], ignore_order: true # true
    match_r 1, 1.0, strict: true               # false
    match_r {1, 2}, {2, 1}, ignore_order: true # false, nope :)
    ...
  end
end

defmodule YourModuleTest do
  use ExUnit.Case
  import RecursiveMatch

  test "some test" do
    ...
    assert_match 1, 2 # false
    assert_match :_, b
    assert_match a, b
    assert_match [1, 2], [2, 1], ignore_order: true
    refute_match 1, 1.0
    assert_match 1, 1.0, strict: false          
    refute_match a, c
    assert_match YourModule.function1(), 1
    ...
  end
end

Options

strict: when true compare using ===, when false compare using ==, default true
ignore_order, when true - ignore order of items in lists, default false
message: Custom message on fail