Awesome
escallmatch
ECMAScript CallExpression matcher made from function/method signature
EXAMPLE
Creating CallExpression matcher for method signature 'assert.equal(actual, expected, [message])'
.
Then match against path/to/some_test.js
.
var escallmatch = require('escallmatch');
var esprima = require('esprima');
var estraverse = require('estraverse');
var fs = require('fs');
var matcher = escallmatch('assert.equal(actual, expected, [message])');
estraverse.traverse(esprima.parse(fs.readFileSync('path/to/some_test.js')), {
enter: function (currentNode, parentNode) {
if (matcher.test(currentNode)) {
// currentNode is a CallExpression that matches to the signature
}
var argMatched = matcher.matchArgument(currentNode, parentNode);
if (argMatched) {
if (argMatched.kind === 'mandatory') {
// mandatory arg (in this case, `actual` or `expected`)
} else if (argMatched.kind === 'optional') {
// optional arg (in this case, `message`)
}
}
}
});
where content of path/to/some_test.js
is:
var assert = require('assert');
var anotherAssert = assert;
var equal = assert.equal.bind(assert);
var foo = '2';
var bar = 2;
assert.equal(foo, bar); // matches
assert.equal(bar, foo); // matches
assert.equal(foo, bar, 'foo shoule be equal to bar'); // matches (with optional arg)
assert.equal(); // does not match (less args)
assert.equal(foo); // does not match (less args)
assert.equal(foo, bar, 'hoge', 'fuga'); // does not match (too much args)
assert.notEqual(foo, bar); // does not match (callee method name differs)
anotherAssert.equal(foo, bar); // does not match (callee object name differs)
equal(foo, bar); // does not match (callee does not match)
escallmatch
is a spin-off product of power-assert project.
Pull-requests, issue reports and patches are always welcomed.
API
var matcher = escallmatch(signatureStr, [options])
Create matcher object for a given function/method signature string.
var matcher = escallmatch('assert.equal(actual, expected, [message])');
Any arguments enclosed in bracket (for example, [message]
) means optional parameters. Without bracket means mandatory parameters.
Returns matcher
object having four methods, test
, matchArgument
, calleeAst
, and argumentSignatures
.
options
an object
for configuration options. If not passed, default options will be used.
options.visitorKeys
type | default value |
---|---|
object | (return value of estraverse.VisitorKeys ) |
VisitorKeys for AST traversal. See estraverse.VisitorKeys and babel.types.VISITOR_KEYS.
options.astWhiteList
type | default value |
---|---|
object | N/A |
Type and property whitelist on creating AST clone. astWhiteList
is an object containing NodeType as keys and properties as values.
{
ArrayExpression: ['type', 'elements'],
ArrayPattern: ['type', 'elements'],
ArrowFunctionExpression: ['type', 'id', 'params', 'body', 'generator', 'expression'],
AssignmentExpression: ['type', 'operator', 'left', 'right'],
...
var isMatched = matcher.test(node)
Tests whether node
matches the signature or not.
- Returns
true
if matched. - Returns
false
if not matched.
node
should be an AST node object defined in Mozilla JavaScript AST spec.
var argMatched = matcher.matchArgument(node, parentNode)
Returns match result object representing whether node
(and its parentNode
) matches some argument of the signature or not.
- Returns
null
if not matched. - If matched, returns object like
{name: 'actual', kind: 'mandatory'}
, whosename
is an argument name in the signature andkind
is'mandatory'
or'optional'
.
node
and parentNode
should be AST node objects defined in Mozilla JavaScript AST spec.
var calleeAst = matcher.calleeAst()
Returns clone of callee AST object based on signature passed to escallmatch
function. Returned tree is one of AST node objects defined in Mozilla JavaScript AST spec (in most cases, Identifier
or MemberExpression
).
var argSigs = matcher.argumentSignatures()
Returns array of argument signature objects based on signature passed to escallmatch
function. Returns array of objects like [{name: 'actual', kind: 'mandatory'}]
, whose name
is an argument name in the signature and kind
is 'mandatory'
or 'optional'
.
INSTALL
via npm
Install
$ npm install --save escallmatch
via bower
Install
$ bower install --save escallmatch
Then load (escallmatch
function is exported)
<script type="text/javascript" src="./path/to/bower_components/escallmatch/build/escallmatch.js"></script>
CHANGELOG
See CHANGELOG
AUTHOR
LICENSE
Licensed under the MIT license.