--- schema_version: "1" id: 177ade6e09d34cef11bd0375c9ec67a15861d11ad49e3bf2631f6bde53120983 title: MUnit DataWeave Assertions Library collection: mulesoft version: current locale: en-us portal_url: https://docs.salesforce.com/mulesoft/current/en-us/munit/latest/dataweave-assertions-library.md canonical_url: https://docs.mulesoft.com/munit/latest/dataweave-assertions-library source_site: docs.mulesoft.com content_type: documentation content_hash: 355bda51995601bad8381a2196675ddf0a8ee70bfe44f8c73e6e9df64c83bb3c description: MuleSoft Documentation Site release: "3.7" latest: true --- --- product: MUnit version: 3.7 is-latest-version: true --- # MUnit DataWeave Assertions Library > For the full documentation index, see: https://docs.mulesoft.com/llms.txt ![logo acb active](/mulesoft/current/en-us/_/img/icons/anypoint-code-builder.svg "Anypoint Code Builder")Anypoint Code Builder ![logo studio active](/mulesoft/current/en-us/_/img/icons/studio.svg "Anypoint Studio")Anypoint Studio The MUnit DataWeave Assertions Library is a set of DataWeave matcher functions for writing assertions in MUnit tests. Use it with the Assert Expression processor to validate values such as strings, numbers, arrays, and objects using DataWeave syntax. ## dw::test::Asserts This module contains the set of core Matchers to use in your tests Example ```dataweave %dw 2.0 import dw::test::Asserts --- payload must beObject() ``` Validates if a payload is of type Object ## Functions ### anyOf #### anyOf(Array>): Matcher Validates that the value satisfies at least one of the given matchers ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must anyOf([beObject(), beString()]) ``` ### beArray #### beArray(): Matcher Validates that a given value is of type Array ```dataweave %dw 2.0 import dw::test::Asserts --- [1, 4, 7] must beArray() ``` ### beBlank #### beBlank(): Matcher Validates that the String value is blank ```dataweave %dw 2.0 import dw::test::Asserts --- " " must beBlank() ``` ### beBoolean #### beBoolean(): Matcher Validates that a given value is of type Boolean ```dataweave %dw 2.0 import dw::test::Asserts --- true must beBoolean() ``` ### beEmpty #### beEmpty(): Matcher Validates that the value (String, Object or Array) is empty ```dataweave %dw 2.0 import dw::test::Asserts --- [] must beEmpty() ``` ### beGreaterThan #### beGreaterThan(Comparable, Boolean): Matcher Validates that the asserted Comparable value is greater than the given one Can be equal to when using the _inclusive_ argument ```dataweave %dw 2.0 import dw::test::Asserts --- 3 must beGreaterThan(2) ``` ### beLowerThan #### beLowerThan(Comparable, Boolean): Matcher Validates that the asserted Comparable value is lower than the given one Can be equal to when using the _inclusive_ argument ```dataweave %dw 2.0 import dw::test::Asserts --- 1 must beLowerThan(2) ``` ### beNull #### beNull(): Matcher Validates that a given value is of type Null ```dataweave %dw 2.0 import dw::test::Asserts --- null must beNull() ``` ### beNumber #### beNumber(): Matcher Validates that a given value is of type Number ```dataweave %dw 2.0 import dw::test::Asserts --- 123 must beNumber() ``` ### beObject #### beObject(): Matcher Validates that a given value is of type Object ```dataweave %dw 2.0 import dw::test::Asserts --- { name : "Lionel", lastName: "Messi"} must beObject() ``` ### beOneOf #### beOneOf(Array): Matcher Validates that the value is contained in the given Array ```dataweave %dw 2.0 import dw::test::Asserts --- 1 must beOneOf([1, "A Text", true]) ``` ### beString #### beString(): Matcher Validates that a given value is of type String ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must beString() ``` ### contain #### contain(String): Matcher Validates that the asserted String contains the given String ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must contain("ex") ``` #### contain(Any): Matcher> Validates that the asserted Array contains the given value ```dataweave %dw 2.0 import dw::test::Asserts --- [1, "A Text", true] must contain(1) ``` ### eachItem #### eachItem(Matcher): Matcher> Validates that each item of the array satisfies the given matcher ```dataweave %dw 2.0 import dw::test::Asserts --- [1,2,3] must eachItem(beNumber()) ``` ### endWith #### endWith(String): Matcher Validates that the asserted String ends with the given String ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must endWith("xt") ``` ### equalTo #### equalTo(Any, { unordered?: Boolean }): Matcher Validates that a value is equal to another one ```dataweave %dw 2.0 import dw::test::Asserts --- (1 + 2) must equalTo(3) ``` ### equalToResource #### equalToResource(String, String, Object): Matcher Validates that the given value is equal to the content of a resource file The resource file must belong to the classpath ```dataweave %dw 2.0 import dw::test::Asserts --- { name: "Lionel", lastName: "Messi" } must equalToResource("user.json", "application/json") ``` ### haveItem #### haveItem(Matcher): Matcher> Validates that at least one item of the array satisfies the given matcher ```dataweave %dw 2.0 import dw::test::Asserts --- [1, true, "a text"] must haveItem(beNumber()) ``` ### haveKey #### haveKey(String): Matcher Validates that the Object has the given key ```dataweave %dw 2.0 import dw::test::Asserts --- { name: "Lionel", lastName: "Messi" } must haveKey("name") ``` ### haveSize #### haveSize(Number): Matcher Validates that the array has the given size ```dataweave %dw 2.0 import dw::test::Asserts --- [1, 4, 7] must haveSize(3) ``` ### haveValue #### haveValue(Any): Matcher Validates that the Object has the given value ```dataweave %dw 2.0 import dw::test::Asserts --- { name: "Lionel", lastName: "Messi" } must haveValue("Messi") ``` ### must #### must(T, Array<(value: T) → Matcher | MatcherResult | Boolean>): MatcherResult This function allows to assert a value with a list of Matcher of Expressions Example ```dataweave %dw 2.0 import dw::test::Asserts --- payload must [ beObject(), $.foo is Null ] ``` #### must(T, (value: T) → Matcher | Boolean): MatcherResult This function allows to assert a value with a Matcher of Expressions Example ```dataweave %dw 2.0 import dw::test::Asserts --- payload must beObject() ``` ### notBe #### notBe(Matcher): Matcher Validates that the value doesn’t satisfy the given matcher ```dataweave %dw 2.0 import dw::test::Asserts --- 1 must notBe(equalTo(2)) ``` ### notBeNull #### notBeNull(): Matcher Validates that a given value isn’t of type Null ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must notBeNull() ``` ### startWith #### startWith(String): Matcher Validates that the asserted String starts with the given String ```dataweave %dw 2.0 import dw::test::Asserts --- "A Text" must startWith("A") ``` ## Variables ### MATCHED Constant that represents a successful match ## Types ### Matcher Data Type that represents a Matcher to perform assertions Example ```dataweave %dw 2.0 import dw::test::Asserts fun beEqualToOne(): Matcher = (actual) -> do { { matches: actual == 1, description: { expected: "To be 1", actual: write(actual) as String } } } ``` Definition ```dataweave (value: T) -> MatcherResult ``` ### MatcherResult Data Type that represents the result of an Assertion Example ```dataweave { "matches": false, description : { expected : "Number type", actual: "A Text" } } ``` Definition ```dataweave { matches: Boolean, description: { expected: String, actual: String }, reasons?: Array } ```