.. | ||
build | ||
LICENSE | ||
package.json | ||
README.md | ||
tsconfig.json | ||
tsconfig.tsbuildinfo |
jest-each
Jest Parameterised TestingA parameterised testing library for Jest inspired by mocha-each.
jest-each allows you to provide multiple arguments to your test
/describe
which results in the test/suite being run once per row of parameters.
Features
.test
to runs multiple tests with parameterised data- Also under the alias:
.it
- Also under the alias:
.test.only
to only run the parameterised tests- Also under the aliases:
.it.only
or.fit
- Also under the aliases:
.test.skip
to skip the parameterised tests- Also under the aliases:
.it.skip
or.xit
or.xtest
- Also under the aliases:
.describe
to runs test suites with parameterised data.describe.only
to only run the parameterised suite of tests- Also under the aliases:
.fdescribe
- Also under the aliases:
.describe.skip
to skip the parameterised suite of tests- Also under the aliases:
.xdescribe
- Also under the aliases:
- Asynchronous tests with
done
- Unique test titles with
printf
formatting:%p
- pretty-format.%s
- String.%d
- Number.%i
- Integer.%f
- Floating point value.%j
- JSON.%o
- Object.%#
- Index of the test case.%%
- single percent sign ('%'). This does not consume an argument.
- 🖖 Spock like data tables with Tagged Template Literals
Demo
Tests without jest-each
Tests can be re-written with jest-each to:
.test
.test
with Tagged Template Literals
.describe
Installation
npm i --save-dev jest-each
yarn add -D jest-each
Importing
jest-each is a default export so it can be imported with whatever name you like.
// es6
import each from 'jest-each';
// es5
const each = require('jest-each');
Array of rows
API
each([parameters]).test(name, testFn)
each
:
- parameters:
Array
of Arrays with the arguments that are passed into thetestFn
for each row- Note If you pass in a 1D array of primitives, internally it will be mapped to a table i.e.
[1, 2, 3] -> [[1], [2], [3]]
- Note If you pass in a 1D array of primitives, internally it will be mapped to a table i.e.
.test
:
- name:
String
the title of thetest
.- Generate unique test titles by positionally injecting parameters with
printf
formatting:%p
- pretty-format.%s
- String.%d
- Number.%i
- Integer.%f
- Floating point value.%j
- JSON.%o
- Object.%#
- Index of the test case.%%
- single percent sign ('%'). This does not consume an argument.
- Generate unique test titles by positionally injecting parameters with
- testFn:
Function
the test logic, this is the function that will receive the parameters of each row as function arguments
each([parameters]).describe(name, suiteFn)
each
:
- parameters:
Array
of Arrays with the arguments that are passed into thesuiteFn
for each row- Note If you pass in a 1D array of primitives, internally it will be mapped to a table i.e.
[1, 2, 3] -> [[1], [2], [3]]
- Note If you pass in a 1D array of primitives, internally it will be mapped to a table i.e.
.describe
:
- name:
String
the title of thedescribe
- Generate unique test titles by positionally injecting parameters with
printf
formatting:%p
- pretty-format.%s
- String.%d
- Number.%i
- Integer.%f
- Floating point value.%j
- JSON.%o
- Object.%#
- Index of the test case.%%
- single percent sign ('%'). This does not consume an argument.
- Generate unique test titles by positionally injecting parameters with
- suiteFn:
Function
the suite oftest
/it
s to be ran, this is the function that will receive the parameters in each row as function arguments
Usage
.test(name, fn)
Alias: .it(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).test(
'returns the result of adding %d to %d',
(a, b, expected) => {
expect(a + b).toBe(expected);
},
);
.test.only(name, fn)
Aliases: .it.only(name, fn)
or .fit(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).test.only(
'returns the result of adding %d to %d',
(a, b, expected) => {
expect(a + b).toBe(expected);
},
);
.test.skip(name, fn)
Aliases: .it.skip(name, fn)
or .xit(name, fn)
or .xtest(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).test.skip(
'returns the result of adding %d to %d',
(a, b, expected) => {
expect(a + b).toBe(expected);
},
);
Asynchronous .test(name, fn(done))
Alias: .it(name, fn(done))
each([['hello'], ['mr'], ['spy']]).test(
'gives 007 secret message: %s',
(str, done) => {
const asynchronousSpy = message => {
expect(message).toBe(str);
done();
};
callSomeAsynchronousFunction(asynchronousSpy)(str);
},
);
.describe(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).describe(
'.add(%d, %d)',
(a, b, expected) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
test('does not mutate first arg', () => {
a + b;
expect(a).toBe(a);
});
test('does not mutate second arg', () => {
a + b;
expect(b).toBe(b);
});
},
);
.describe.only(name, fn)
Aliases: .fdescribe(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).describe.only(
'.add(%d, %d)',
(a, b, expected) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
},
);
.describe.skip(name, fn)
Aliases: .xdescribe(name, fn)
each([[1, 1, 2], [1, 2, 3], [2, 1, 3]]).describe.skip(
'.add(%d, %d)',
(a, b, expected) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
},
);
Tagged Template Literal of rows
API
each[tagged template].test(name, suiteFn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.test('returns $expected when adding $a to $b', ({a, b, expected}) => {
expect(a + b).toBe(expected);
});
each
takes a tagged template string with:
- First row of variable name column headings seperated with
|
- One or more subsequent rows of data supplied as template literal expressions using
${value}
syntax.
.test
:
- name:
String
the title of thetest
, use$variable
in the name string to inject test values into the test title from the tagged template expressions- To inject nested object values use you can supply a keyPath i.e.
$variable.path.to.value
- To inject nested object values use you can supply a keyPath i.e.
- testFn:
Function
the test logic, this is the function that will receive the parameters of each row as function arguments
each[tagged template].describe(name, suiteFn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.describe('$a + $b', ({a, b, expected}) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
test('does not mutate first arg', () => {
a + b;
expect(a).toBe(a);
});
test('does not mutate second arg', () => {
a + b;
expect(b).toBe(b);
});
});
each
takes a tagged template string with:
- First row of variable name column headings seperated with
|
- One or more subsequent rows of data supplied as template literal expressions using
${value}
syntax.
.describe
:
- name:
String
the title of thetest
, use$variable
in the name string to inject test values into the test title from the tagged template expressions- To inject nested object values use you can supply a keyPath i.e.
$variable.path.to.value
- To inject nested object values use you can supply a keyPath i.e.
- suiteFn:
Function
the suite oftest
/it
s to be ran, this is the function that will receive the parameters in each row as function arguments
Usage
.test(name, fn)
Alias: .it(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.test('returns $expected when adding $a to $b', ({a, b, expected}) => {
expect(a + b).toBe(expected);
});
.test.only(name, fn)
Aliases: .it.only(name, fn)
or .fit(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.test.only('returns $expected when adding $a to $b', ({a, b, expected}) => {
expect(a + b).toBe(expected);
});
.test.skip(name, fn)
Aliases: .it.skip(name, fn)
or .xit(name, fn)
or .xtest(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.test.skip('returns $expected when adding $a to $b', ({a, b, expected}) => {
expect(a + b).toBe(expected);
});
Asynchronous .test(name, fn(done))
Alias: .it(name, fn(done))
each`
str
${'hello'}
${'mr'}
${'spy'}
`.test('gives 007 secret message: $str', ({str}, done) => {
const asynchronousSpy = message => {
expect(message).toBe(str);
done();
};
callSomeAsynchronousFunction(asynchronousSpy)(str);
});
.describe(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.describe('$a + $b', ({a, b, expected}) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
test('does not mutate first arg', () => {
a + b;
expect(a).toBe(a);
});
test('does not mutate second arg', () => {
a + b;
expect(b).toBe(b);
});
});
.describe.only(name, fn)
Aliases: .fdescribe(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.describe.only('$a + $b', ({a, b, expected}) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
});
.describe.skip(name, fn)
Aliases: .xdescribe(name, fn)
each`
a | b | expected
${1} | ${1} | ${2}
${1} | ${2} | ${3}
${2} | ${1} | ${3}
`.describe.skip('$a + $b', ({a, b, expected}) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected);
});
});
License
MIT