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babel-plugin-espower
Advanced tools
Babel plugin for power-assert.
babel-plugin-espower is a Babel plugin for power-assert.
power-assert provides descriptive assertion messages for your tests, like this.
1) ES6 demo Destructuring and TemplateLiteral:
AssertionError: # test/demo_test.js:7
assert(`${ alice.name } and ${ bob.name }` === `bob and alice`)
| | | | | | |
| | | | | | "bob and alice"
| | | | "bob" false
| | "alice" Object{name:"bob"}
| Object{name:"alice"}
"alice and bob"
--- [string] `bob and alice`
+++ [string] `${ alice.name } and ${ bob.name }`
@@ -1,13 +1,13 @@
-bob and alice
+alice and bob
Pull-requests, issue reports and patches are always welcomed. See power-assert project for more documentation.
FYI: There's a babel preset for all power-assert plugins
$ npm install --save-dev babel-plugin-espower
Babel7 is incompatible with Babel6. Babel6 is incompatible with Babel5.
For Babel6, you need to use the 2.x release of babel-plugin-espower.
$ npm install --save-dev babel-plugin-espower@2
For Babel5 or lower, you need to use the 1.x release of babel-plugin-espower.
$ npm install --save-dev babel-plugin-espower@1
{
"presets": [
...
],
"plugins": [
"babel-plugin-espower"
]
}
$ babel /path/to/test/some_test.js > /path/to/build/some_test.js
For example, with @babel/register module and .babelrc above, you can run mocha without code generation steps.
$ $(npm bin)/mocha --require @babel/register test/some_test.js
var babel = require('@babel/core');
var jsCode = fs.readFileSync('/path/to/test/some_test.js');
var transformed = babel.transform(jsCode, {
presets: [...],
plugins: ['babel-plugin-espower']
});
console.log(transformed.code);
require('@babel/register')({
presets: [...],
plugins: ['babel-plugin-espower']
});
For example, with babel_hook.js above, you can run mocha without code generation steps.
$ $(npm bin)/mocha --require ./babel_hook /path/to/test/demo_test.js
var fs = require('fs');
var browserify = require('browserify');
var babelify = require('babelify');
var glob = require('glob'),
browserify({ entries: glob.sync('./test/*_test.js'), debug: true })
.transform(babelify.configure({
presets: [...],
plugins: ['babel-plugin-espower']
}))
.bundle()
.on('error', function (err) { console.log('Error : ' + err.message); })
.pipe(fs.createWriteStream('all_test.js'));
$ $(npm bin)/browserify -d -e ./test/*_test.js -t [ babelify --presets ... --plugins babel-plugin-espower ]
var source = require('vinyl-source-stream');
var browserify = require('browserify');
var glob = require('glob'),
gulp.task('build_test', function() {
var files = glob.sync('./test/*_test.js');
var b = browserify({entries: files, debug: true});
b.transform(babelify.configure({
presets: [...],
plugins: ['babel-plugin-espower']
}));
return b.bundle()
.pipe(source('all_test.js'))
.pipe(gulp.dest('./build'));
});
module.exports = function(config) {
config.set({
frameworks: ['mocha', 'browserify'],
files: [
"test/**/*.js"
],
preprocessors: {
"test/**/*.js": "browserify"
},
browserify: {
debug: true,
transform: [
[
'babelify', {
presets: [...],
plugins: ['babel-plugin-espower']
}
]
]
},
// ...
For given test file test/demo_test.js below,
import assert from 'power-assert';
describe('ES6 demo', () => {
it('Destructuring and TemplateLiteral', () => {
let [alice, bob] = [ { name: 'alice' }, { name: 'bob' } ];
assert(`${alice.name} and ${bob.name}` === `bob and alice`);
});
it('ArrowFunctionExpression and SpreadElement', () => {
let seven = 7, ary = [4, 5];
assert(seven === ((v, i) => v + i)(...[...ary]));
});
it('Enhanced Object Literals', () => {
let name = 'bobby';
assert.deepEqual({
name,
[ `${name}'s greet` ]: `Hello, I'm ${name}`
}, null);
});
});
prepare babel_hook.js to transform tests.
{
"presets": [
...
],
"plugins": [
"babel-plugin-espower"
]
}
Run mocha with --require @babel/register option. You will see the power-assert output appears.
$ $(npm bin)/mocha --require @babel/register test/demo_test.js
ES6 demo
1) Destructuring and TemplateLiteral
2) ArrowFunctionExpression and SpreadElement
3) Enhanced Object Literals
0 passing
3 failing
1) ES6 demo Destructuring and TemplateLiteral:
AssertionError: # test/demo_test.js:7
assert(`${ alice.name } and ${ bob.name }` === `bob and alice`)
| | | | | | |
| | | | | | "bob and alice"
| | | | "bob" false
| | "alice" Object{name:"bob"}
| Object{name:"alice"}
"alice and bob"
--- [string] `bob and alice`
+++ [string] `${ alice.name } and ${ bob.name }`
@@ -1,13 +1,13 @@
-bob and alice
+alice and bob
at Context.<anonymous> (test/demo_test.js:19:28)
2) ES6 demo ArrowFunctionExpression and SpreadElement:
AssertionError: # test/demo_test.js:12
assert(seven === ((v, i) => v + i)(...[...ary]))
| | | | |
| | | | [4,5]
| | 9 [4,5]
7 false
[number] ((v, i) => v + i)(...[...ary])
=> 9
[number] seven
=> 7
at Context.<anonymous> (test/demo_test.js:29:28)
3) ES6 demo Enhanced Object Literals:
AssertionError: # test/demo_test.js:17
assert.deepEqual({name,[`${ name }'s greet`]: `Hello, I'm ${ name }`}, null)
| | | | |
| | | | "bobby"
| | "bobby" "Hello, I'm bobby"
| "bobby's greet"
Object{name:"bobby","bobby's greet":"Hello, I'm bobby"}
at Context.<anonymous> (test/demo_test.js:40:29)
You can customize configs such as assertion patterns via .babelrc
{
"presets": [
...
],
"plugins": [
["babel-plugin-espower", {
"embedAst": true,
"patterns": [
"assert.isNull(object, [message])",
"assert.same(actual, expected, [message])",
"assert.near(actual, expected, delta, [message])"
]
}]
]
}
or via Require Hook.
require('@babel/register')({
presets: [...],
plugins: [
['babel-plugin-espower', {
embedAst: true,
patterns: [
'assert.isNull(object, [message])',
'assert.same(actual, expected, [message])',
'assert.near(actual, expected, delta, [message])'
]
}]
]
});
or via Babel API,
var babel = require('@babel/core');
var jsCode = fs.readFileSync('/path/to/test/some_test.js');
var transformed = babel.transform(jsCode, {
presets: [...],
plugins: [
['babel-plugin-espower', {
embedAst: true,
patterns: [
'assert.isNull(object, [message])',
'assert.same(actual, expected, [message])',
'assert.near(actual, expected, delta, [message])'
]
}]
]
});
console.log(transformed.code);
| type | default value |
|---|---|
object | objects shown below |
Configuration options for babel-plugin-espower. If not passed, default options will be used (return value of defaultOptions() with default embedAst, visitorKeys, astWhiteList, path, sourceRoot and sourceMap. visitorKeys is value of babel.types.VISITOR_KEYS. astWhiteList is value of babel.types.BUILDER_KEYS. path is filename passed to babel. sourceRoot is be return value of process.cwd(), sourceMap is babel's internal SourceMap object).
{
patterns: [
'assert(value, [message])',
'assert.ok(value, [message])',
'assert.equal(actual, expected, [message])',
'assert.notEqual(actual, expected, [message])',
'assert.strictEqual(actual, expected, [message])',
'assert.notStrictEqual(actual, expected, [message])',
'assert.deepEqual(actual, expected, [message])',
'assert.notDeepEqual(actual, expected, [message])',
'assert.deepStrictEqual(actual, expected, [message])',
'assert.notDeepStrictEqual(actual, expected, [message])'
],
embedAst: true,
visitorKeys: babel.types.VISITOR_KEYS,
astWhiteList: babel.types.BUILDER_KEYS,
sourceRoot: process.cwd(),
path: file.opts.filename,
sourceMap: file.inputMap ? file.inputMap.toObject() : false
}
If you want to use non-ECMASCript-standard features such as JSX tags in your assert(), you should set embedAst option to true.
assert(shallow(<Foo />).is('.foo'));
See CHANGELOG
We support Node under maintenance. In other words, we stop supporting old Node version when their maintenance ends.
This means that any other environment is not supported.
NOTE: If babel-plugin-espower works in any of the unsupported environments, it is purely coincidental and has no bearing on future compatibility. Use at your own risk.
Licensed under the MIT license.
FAQs
Babel plugin for power-assert
The npm package babel-plugin-espower receives a total of 58,071 weekly downloads. As such, babel-plugin-espower popularity was classified as popular.
We found that babel-plugin-espower demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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