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josephwilk/amrita

A polite, well mannered and thoroughly upstanding testing framework for Elixir

josephwilk/amrita.json
{
"createdAt": "2013-05-30T12:36:17Z",
"defaultBranch": "master",
"description": "A polite, well mannered and thoroughly upstanding testing framework for Elixir",
"fullName": "josephwilk/amrita",
"homepage": "",
"language": "Elixir",
"name": "amrita",
"pushedAt": "2017-07-07T14:41:26Z",
"stargazersCount": 198,
"topics": [
"testing"
],
"updatedAt": "2025-11-08T21:42:26Z",
"url": "https://github.com/josephwilk/amrita"
}

Build Status

A polite, well mannered and thoroughly upstanding testing framework for Elixir.

Elixir of life

Add to your mix.exs

defp deps do
[
{:amrita, "~>0.4", github: "josephwilk/amrita"}
]
end

After adding Amrita as a dependency, to install please run:

Terminal window
mix deps.get

Ensure you start Amrita in: test/test_helper.exs

Amrita.start
#Or if you want a more documentation focused formatter:
Amrita.start(formatter: Amrita.Formatter.Documentation)
  • Require test_helper.exs in every test (this will ensure Amrita is started):
  • Mix in Amrita.Sweet which will bring in everything you need to use Amrita:
Code.require_file "../test_helper.exs", __ENV__.file
defmodule ExampleFacts do
use Amrita.Sweet
fact "addition" do
1 + 1 |> 2
end
end

Run your tests through mix:

Terminal window
$ mix amrita # Run all your tests
$ mix amrita test/integration/t_mocks.ex # Run a specific file
$ mix amrita test/integration/t_mocks.ex:10 # Run a specific test at a line number
$ mix amrita --trace # Show execution time for slow tests

Now time to write some tests!

Amrita supports BDD style mocks.

Examples:

defmodule Polite do
def swear? do
false
end
def swear?(word) do
false
end
end
fact "mock with a wildcard" do
provided [Polite.swear? |> true] do
Polite.swear? |> truthy
end
end
fact "mock with a wildcard"
provided [Polite.swear?(_) |> true] do
Polite.swear?(:yes) |> truthy
Polite.swear?(:whatever) |> truthy
end
end

Powerful custom predicates for argument matching

Section titled “Powerful custom predicates for argument matching”
fact "mock with a matcher function" do
provided [Polite.swear?(fn arg -> arg =~ ~r"moo") |> false] do
Polite.swear?("its ok to moo really") |> falsey
end
end

Return values based on specific argument values

Section titled “Return values based on specific argument values”
fact "mock with return based on argument" do
provided [Polite.swear?(:pants) |> false,
Polite.swear?(:bugger) |> true] do
Funk.swear?(:pants) |> falsey
Funk.swear?(:bugger) |> truthy
end
end

Polite Errors explaining when things went wrong

Section titled “Polite Errors explaining when things went wrong”

Polite mock error message

Amrita is also all about checker based testing!

Code.require_file "../test_helper.exs", __ENV__.file
defmodule ExampleFacts do
use Amrita.Sweet
facts "about Amrita checkers" do
fact "`equals` checks equality" do
1 - 10 |> equals -9
# For convience the default checker is equals
# So we can write the above as
1 - 10 |> -9
# Pattern matching with tuples
{ 1, 2, { 3, 4 } } |> equals {1, _, { _, 4 } }
# Which is the same as
{ 1, 2, { 3, 4 } } |> {1, _, { _, 4 } }
end
fact "contains checks if an element is in a collection" do
[1, 2, 4, 5] |> contains 4
{6, 7, 8, 9} |> contains 9
[a: 1, :b 2] |> contains {:a, 1}
end
fact "! negates a checker" do
[1, 2, 3, 4] |> !contains 9999
# or you can add a space, like this. Whatever tickles your fancy.
[1, 2, 3, 4] |> ! contains 9999
10 |> ! equal 11
end
fact "contains works with strings" do
"mad hatters tea party" |> contains "hatters"
"mad hatter tea party" |> contains ~r"h(\w+)er"
end
fact "has_prefix checks if the start of a collection matches" do
[1, 2, 3, 4] |> has_prefix [1, 2]
{1, 2, 3, 4} |> has_prefix {1, 2}
"I cannot explain myself for I am not myself" |> has_prefix "I"
end
fact "has_prefix with a Set ignores the order" do
{1, 2, 3, 4} |> has_prefix Set.new([{2, 1}])
end
fact "has_suffix checks if the end of a collection matches" do
[1, 2, 3, 4 ,5] |> has_suffix [4, 5]
{1, 2, 3, 4} |> has_suffix {3, 4}
"I cannot explain myself for I am not myself" |> has_suffix "myself"
end
fact "has_suffix with a Set ignores the order" do
{1, 2, 3, 4} |> has_suffix Set.new([{4, 3}])
end
fact "for_all checks if a predicate holds for all elements" do
[2, 4, 6, 8] |> for_all even(&1)
# or alternatively you could write
[2, 4, 6, 8] |> Enum.all? even(&1)
end
fact "odd checks if a number is, well odd" do
1 |> odd
end
fact "even checks is a number if even" do
2 |> even
end
fact "roughly checks if a float within some +-delta matches" do
0.1001 |> roughly 0.1
end
fact "falsey checks if expression evalulates to false" do
nil |> falsey
end
fact "truthy checks if expression evaulates to true" do
"" |> truthy
end
defexception Boom, message: "Golly gosh"
fact "raises checks if an exception was raised" do
fn -> raise Boom end |> raises ExampleFacts.Boom
end
end
future_fact "I'm not run yet, just printed as a reminder. Like a TODO" do
# Never run
false |> truthy
end
fact "a fact without a body is much like a TODO"
# Backwards compatible with ExUnit
test "arithmetic" do
assert 1 + 1 == 2
end
end

The syntax for assertions is as follows:

# Equality check
ACTUAL |> [EXPECTED]
# Not equal check
ACTUAL |> ! [EXPECTED]
# Using a checker function
ACTUAL |> CHECKER [EXPECTED]
# or negative form
ACTUAL |> !CHECKER [EXPECTED]

##Custom checkers

Its simple to create your own checkers:

defchecker a_thousand(actual) do
rem(actual, 1000) |> equals 0
end
fact "about 1000s" do
1000 |> a_thousand # true
1200 |> ! a_thousand # true
end

Amrita tries its best to be polite with its errors:

Polite error message

Checkout an example using Amrita with Dynamo: https://github.com/elixir-amrita/amrita_with_dynamo

See the wiki for various IDE plugins for Amrita: https://github.com/josephwilk/amrita/wiki/Plugins

Hacking on Amrita.

###Running tests

Amrita runs tests against Elixir’s latest stable release and against Elixir master. Make is your friend for running these tests:

# Run lastest stable and elixir master
make ci
# Run tests against your current Elixir install
make

http://josephwilk.github.io/amrita/docs

Thanks for reading me, I appreciate it.

Have a good day.

Maybe drink some tea.

Its good for the constitution.

Tea

##License (The MIT License)

Copyright (c) 2014-2016 Joseph Wilk

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.