9.8 KiB
samsam
Same same, but different
samsam is a collection of predicate and comparison
functions useful for identifiying the type of values and to compare
values with varying degrees of strictness.
samsam is a general-purpose library. It works in
browsers and Node. It will define itself as an AMD module if you want it
to (i.e. if there’s a define function available).
Predicate functions
isArguments(value)
Returns true if value is an
arguments object, false otherwise.
isNegZero(value)
Returns true if value is
-0.
isElement(value)
Returns true if value is a DOM element
node. Unlike Underscore.js/lodash, this function will return
false if value is an element-like
object, i.e. a regular object with a nodeType property that
holds the value 1.
isSet(value)
Returns true if value is a Set.
Comparison functions
identical(x, y)
Strict equality check according to EcmaScript Harmony’s
egal.
From the Harmony wiki:
An egal function simply makes available the internal
SameValuefunction from section 9.12 of the ES5 spec. If two values are egal, then they are not observably distinguishable.
identical returns true when
=== is true, except for -0 and
+0, where it returns false. Additionally, it
returns true when NaN is compared to
itself.
deepEqual(actual, expectation)
Deep equal comparison. Two values are “deep equal” if:
They are identical
They are both date objects representing the same time
They are both arrays containing elements that are all deepEqual
They are objects with the same set of properties, and each property in
actualis deepEqual to the corresponding property inexpectationactualcan have symbolic properties that are missing fromexpectation
Matcher
Match values and objects by type or or other fuzzy criteria.
samsam ships with these built in matchers:
sinon.match.any
Matches anything.
sinon.match.defined
Requires the value to be defined.
sinon.match.truthy
Requires the value to be truthy.
sinon.match.falsy
Requires the value to be falsy.
sinon.match.bool
Requires the value to be a Boolean
sinon.match.number
Requires the value to be a Number.
sinon.match.string
Requires the value to be a String.
sinon.match.object
Requires the value to be an Object.
sinon.match.func
Requires the value to be a Function.
sinon.match.array
Requires the value to be an Array.
sinon.match.array.deepEquals(arr)
Requires an Array to be deep equal another one.
sinon.match.array.startsWith(arr)
Requires an Array to start with the same values as
another one.
sinon.match.array.endsWith(arr)
Requires an Array to end with the same values as another
one.
sinon.match.array.contains(arr)
Requires an Array to contain each one of the values the
given array has.
sinon.match.map
Requires the value to be a Map.
sinon.match.map.deepEquals(map)
Requires a Map to be deep equal another one.
sinon.match.map.contains(map)
Requires a Map to contain each one of the items the
given map has.
sinon.match.set
Requires the value to be a Set.
sinon.match.set.deepEquals(set)
Requires a Set to be deep equal another one.
sinon.match.set.contains(set)
Requires a Set to contain each one of the items the
given set has.
sinon.match.regexp
Requires the value to be a regular expression.
sinon.match.date
Requires the value to be a Date object.
sinon.match.symbol
Requires the value to be a Symbol.
sinon.match.in(array)
Requires the value to be in the array.
sinon.match.same(ref)
Requires the value to strictly equal ref.
sinon.match.typeOf(type)
Requires the value to be of the given type, where type
can be one of "undefined", "null",
"boolean", "number", "string",
"object", "function", "array",
"regexp", "date" or "symbol".
sinon.match.instanceOf(type)
Requires the value to be an instance of the given
type.
sinon.match.has(property[, expectation])
Requires the value to define the given property.
The property might be inherited via the prototype chain. If the optional expectation is given, the value of the property is deeply compared with the expectation. The expectation can be another matcher.
sinon.match.hasOwn(property[, expectation])
Same as sinon.match.has but the property must be defined
by the value itself. Inherited properties are ignored.
sinon.match.hasNested(propertyPath[, expectation])
Requires the value to define the given propertyPath. Dot
(prop.prop) and bracket (prop[0]) notations
are supported as in Lodash.get.
The propertyPath might be inherited via the prototype chain. If the optional expectation is given, the value at the propertyPath is deeply compared with the expectation. The expectation can be another matcher.
sinon.match.hasNested("a[0].b.c");
// Where actual is something like
var actual = { "a": [{ "b": { "c": 3 } }] };
sinon.match.hasNested("a.b.c");
// Where actual is something like
var actual = { "a": { "b": { "c": 3 } } };sinon.match.every(matcher)
Requires every element of an Array,
Set or Map, or alternatively
every value of an Object to match the
given matcher.
sinon.match.some(matcher)
Requires any element of an Array,
Set or Map, or alternatively
any value of an Object to match the given
matcher.
Combining matchers
All matchers implement and and or. This
allows to logically combine mutliple matchers. The result is a new
matchers that requires both (and) or one of the matchers (or) to return
true.
var stringOrNumber = sinon.match.string.or(sinon.match.number);
var bookWithPages = sinon.match.instanceOf(Book).and(sinon.match.has("pages"));match(object, matcher)
Creates a custom matcher to perform partial equality check. Compares
object with matcher according a wide set of rules:
String matcher
In its simplest form, match performs a case insensitive
substring match. When the matcher is a string, object is
converted to a string, and the function returns true if the
matcher is a case-insensitive substring of object as a
string.
samsam.match("Give me something", "Give"); //true
samsam.match("Give me something", "sumptn"); // false
samsam.match({ toString: function () { return "yeah"; } }, "Yeah!"); // trueThe last example is not symmetric. When the matcher is a string, the
object is coerced to a string - in this case using
toString. Changing the order of the arguments would cause
the matcher to be an object, in which case different rules apply (see
below).
Boolean matcher
Performs a strict (i.e. ===) match with the object. So,
only true matches true, and only
false matches false.
Regular expression matcher
When the matcher is a regular expression, the function will pass if
object.test(matcher) is true.
match is written in a generic way, so any object with a
test method will be used as a matcher this way.
samsam.match("Give me something", /^[a-z\s]$/i); // true
samsam.match("Give me something", /[0-9]/); // false
samsam.match({ toString: function () { return "yeah!"; } }, /yeah/); // true
samsam.match(234, /[a-z]/); // falseNumber matcher
When the matcher is a number, the assertion will pass if
object == matcher.
samsam.match("123", 123); // true
samsam.match("Give me something", 425); // false
samsam.match({ toString: function () { return "42"; } }, 42); // true
samsam.match(234, 1234); // falseFunction matcher
When the matcher is a function, it is called with object
as its only argument. match returns true if
the function returns true. A strict match is performed
against the return value, so a boolean true is required,
truthy is not enough.
// true
samsam.match("123", function (exp) {
return exp == "123";
});
// false
samsam.match("Give me something", function () {
return "ok";
});
// true
samsam.match({
toString: function () {
return "42";
}
}, function () { return true; });
// false
samsam.match(234, function () {});Object matcher
As mentioned above, if an object matcher defines a test
method, match will return true if
matcher.test(object) returns truthy.
If the matcher does not have a test method, a recursive match is
performed. If all properties of matcher matches
corresponding properties in object, match
returns true. Note that the object matcher does not care if
the number of properties in the two objects are the same - only if all
properties in the matcher recursively matches ones in
object. If supported, this object matchers include symbolic
properties in the comparison.
// true
samsam.match("123", {
test: function (arg) {
return arg == 123;
}
});
// false
samsam.match({}, { prop: 42 });
// true
samsam.match({
name: "Chris",
profession: "Programmer"
}, {
name: "Chris"
});
// false
samsam.match(234, { name: "Chris" });DOM elements
match can be very helpful when comparing DOM elements,
because it allows you to compare several properties with one call:
var el = document.getElementById("myEl");
samsam.match(el, {
tagName: "h2",
className: "item",
innerHTML: "Howdy"
});