22.362cd32f.js

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For example you might have a component like this:")]),t._v(" "),a("div",{staticClass:"language-js extra-class"},[a("pre",{pre:!0,attrs:{class:"language-js"}},[a("code",[a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" ComplexComponent "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n  components"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v(" ComplexA"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" ComplexB"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" ComplexC "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n  template"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token template-string"}},[a("span",{pre:!0,attrs:{class:"token template-punctuation string"}},[t._v("`")]),a("span",{pre:!0,attrs:{class:"token string"}},[t._v("\n    <div>\n      <h1>Welcome to Vue.js 3</h1>\n      <ComplexA />\n      <ComplexB />\n      <ComplexC />\n    </div>\n  ")]),a("span",{pre:!0,attrs:{class:"token template-punctuation string"}},[t._v("`")])]),t._v("\n"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v("\n")])])]),a("p",[t._v("Imagine each of the "),a("code",[t._v("<Complex>")]),t._v(" does something complicated, and you are only interested in testing that the "),a("code",[t._v("<h1>")]),t._v(" is rendering the correct greeting. You could do something like:")]),t._v(" "),a("div",{staticClass:"language-js extra-class"},[a("pre",{pre:!0,attrs:{class:"language-js"}},[a("code",[a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" wrapper "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token function"}},[t._v("mount")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),t._v("ComplexComponent"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n  global"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n    stubs"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n      ComplexA"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token boolean"}},[t._v("true")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n      ComplexB"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token boolean"}},[t._v("true")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n      ComplexC"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token boolean"}},[t._v("true")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n    "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v("\n  "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v("\n"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v("\n")])])]),a("p",[t._v("But that's a lot of boilerplate. VTU has a "),a("code",[t._v("shallow")]),t._v(" mounting option that will automatically stub out all the child components:")]),t._v(" "),a("div",{staticClass:"language-js extra-class"},[a("div",{staticClass:"highlight-lines"},[a("br"),a("br"),a("br"),a("br"),a("div",{staticClass:"highlighted"},[t._v(" ")]),a("br"),a("br")]),a("pre",{pre:!0,attrs:{class:"language-js"}},[a("code",[a("span",{pre:!0,attrs:{class:"token function"}},[t._v("test")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),a("span",{pre:!0,attrs:{class:"token string"}},[t._v("'shallow'")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=>")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n  "),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("const")]),t._v(" wrapper "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token function"}},[t._v("monut")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),t._v("ComplexComponent"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n    shallow"),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v(":")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token boolean"}},[t._v("true")]),t._v("\n  "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v("\n  console"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),a("span",{pre:!0,attrs:{class:"token function"}},[t._v("log")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),t._v("wrapper"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),a("span",{pre:!0,attrs:{class:"token function"}},[t._v("html")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token comment"}},[t._v("// <div><h1>Welcome to Vue.js 3</h1><complex-a-stub></complex-a-stub><complex-b-stub></complex-b-stub><complex-c-stub></complex-c-stub></div>")]),t._v("\n"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v("\n")])])]),a("blockquote",[a("p",[t._v("TIP: If you used VTU V1, you may remember this as "),a("code",[t._v("shallowMount")]),t._v(". That method is still available, too - it's the same as writing "),a("code",[t._v("shallow: true")]),t._v(".")])]),t._v(" "),a("h2",{attrs:{id:"default-slots-and-shallow"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#default-slots-and-shallow"}},[t._v("#")]),t._v(" Default Slots and "),a("code",[t._v("shallow")])]),t._v(" "),a("p",[t._v("Since "),a("code",[t._v("shallow")]),t._v(" stubs out all the content of a components, any "),a("code",[t._v("<slot>")]),t._v(" won't get rendered when using "),a("code",[t._v("shallow")]),t._v(". 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That means you won't be able to verify the correct text is rendered! For this use case, you can use "),a("code",[t._v("config.renderDefaultStub")]),t._v(", which will render the default "),a("code",[t._v("<slot />")]),t._v(", even when using "),a("code",[t._v("shallow")]),t._v(":")]),t._v(" "),a("div",{staticClass:"language-js extra-class"},[a("div",{staticClass:"highlight-lines"},[a("div",{staticClass:"highlighted"},[t._v(" ")]),a("br"),a("br"),a("div",{staticClass:"highlighted"},[t._v(" ")]),a("br"),a("br"),a("br"),a("div",{staticClass:"highlighted"},[t._v(" ")]),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br"),a("br")]),a("pre",{pre:!0,attrs:{class:"language-js"}},[a("code",[a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("import")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v(" config"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" mount "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v(" 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tip"},[a("p",{staticClass:"custom-block-title"},[t._v("If you prefer this behavior, you can enable this globally by importing `config` in your test setup file, and setting `renderStubDefaultSlot` to `true`. Unfortunately, due to technical limitations, this behavior is not extended to slots other than the default slot.")]),t._v(" "),a("h2",{attrs:{id:"mount-shallow-and-stubs-which-one-and-when"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#mount-shallow-and-stubs-which-one-and-when"}},[t._v("#")]),t._v(" "),a("code",[t._v("mount")]),t._v(", "),a("code",[t._v("shallow")]),t._v(" and "),a("code",[t._v("stubs")]),t._v(": which one and when?")]),t._v(" "),a("p",[t._v("As a rule of thumb, the more your tests resemble the way your software is used, the more confidence they can give you.")]),t._v(" "),a("p",[t._v("Tests that use "),a("code",[t._v("mount")]),t._v(" will render the entire component hierarchy, which is closer to what the user will experience in a real browser.")]),t._v(" "),a("p",[t._v("On the other hand, tests using "),a("code",[t._v("shallow")]),t._v(" are focused on a specific component. "),a("code",[t._v("shallow")]),t._v(" can be useful for testing advanced components in complete isolation. If you just have one or two components that are not relevant to your tests, consider using "),a("code",[t._v("mount")]),t._v(" in combination with "),a("code",[t._v("stubs")]),t._v(" instead of "),a("code",[t._v("shallow")]),t._v(". The more you stub, the less production-like your test becomes.")]),t._v(" "),a("p",[t._v("Keep in mind that whether you are doing a full mount or a shallow render, good tests focus on inputs ("),a("code",[t._v("props")]),t._v(" and user interaction, such as with "),a("code",[t._v("trigger")]),t._v(") and outputs (the DOM elements that are rendered, and events), not implementation details.")]),t._v(" "),a("p",[t._v("So regardless of which mounting method you choose, we suggest keeping these guidelines in mind.")]),t._v(" "),a("h2",{attrs:{id:"conclusion"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#conclusion"}},[t._v("#")]),t._v(" Conclusion")]),t._v(" "),a("ul",[a("li",[t._v("use "),a("code",[t._v("global.stubs")]),t._v(" to replace a component with a dummy one to simplify your tests")]),t._v(" "),a("li",[t._v("use "),a("code",[t._v("shallow: true")]),t._v(" (or "),a("code",[t._v("shallowMount")]),t._v(") to stub out all child components")]),t._v(" "),a("li",[t._v("use "),a("code",[t._v("config.stubRenderDefaultSlot")]),t._v(" to render the default "),a("code",[t._v("<slot>")]),t._v(" for a stubbed component")])])])])}),[],!1,null,null,null);s.default=e.exports}}]);