feat(menu-item): add multipleSelection property to display a check icon

src/components/menu/MenuItem.js

@@ -1,4 +1,4 @@
-import { html } from "lit"
+import { html, nothing } from "lit"
 import { ifDefined } from "lit/directives/if-defined.js"
 
 import { LeuElement } from "../../lib/LeuElement.js"
@@ -15,6 +15,7 @@ import styles from "./menu-item.css"
  * @tagname leu-menu-item
  * @slot - The label of the menu item
  * @property {boolean} active - Defines if the item is selected or checked
+ * @property {boolean} multipleSelection - If the item is part of a multiple selection. Renders a checkmark before the label when active
  * @property {boolean} disabled - Disables the underlying button or link
  * @property {string} value - The value of the item. It must not contain commas. See `getValue()`
  * @property {string} href - The href of the underlying link
@@ -38,6 +39,11 @@ export class LeuMenuItem extends LeuElement {
 
   static properties = {
     active: { type: Boolean, reflect: true },
+    multipleSelection: {
+      type: Boolean,
+      reflect: true,
+      attr: "multiple-selection",
+    },
     disabled: { type: Boolean, reflect: true },
     tabbable: { type: Boolean, reflect: true },
     href: { type: String, reflect: true },
@@ -50,6 +56,7 @@ export class LeuMenuItem extends LeuElement {
 
     this.active = false
     this.disabled = false
+    this.multipleSelection = false
     this.value = undefined
     this.href = undefined
     this.tabbable = undefined
@@ -142,9 +149,21 @@ export class LeuMenuItem extends LeuElement {
     </button>`
   }
 
+  _renderBeforeSlotDefault() {
+    if (!this.multipleSelection) {
+      return nothing
+    }
+
+    return this.active
+      ? html`<leu-icon name="check"></leu-icon>`
+      : html`<leu-icon></leu-icon>`
+  }
+
   render() {
     const content = html`
-      <slot class="before" name="before"></slot>
+      <slot class="before" name="before"
+        >${this._renderBeforeSlotDefault()}</slot
+      >
       <span class="label"><slot></slot></span>
       <slot class="after" name="after"></slot>
     `

src/components/menu/stories/menu-item.stories.js

@@ -1,4 +1,4 @@
-import { html } from "lit"
+import { html, nothing } from "lit"
 import { ifDefined } from "lit/directives/if-defined.js"
 
 import "../leu-menu-item.js"
@@ -29,14 +29,19 @@ function Template(args) {
       href=${ifDefined(args.href)}
       ?active=${args.active}
       ?disabled=${args.disabled}
+      ?multipleSelection=${args.multipleSelection}
     >
-      ${isIcon(args.before)
-        ? html`<leu-icon slot="before" name=${args.before}></leu-icon>`
-        : html`<span slot="before">${args.before}</span>`}
+      ${args.before
+        ? isIcon(args.before)
+          ? html`<leu-icon slot="before" name=${args.before}></leu-icon>`
+          : html`<span slot="before">${args.before}</span>`
+        : nothing}
       ${args.label}
-      ${isIcon(args.after)
-        ? html`<leu-icon slot="after" name=${args.after}></leu-icon>`
-        : html`<span slot="after">${args.after}</span>`}
+      ${args.after
+        ? isIcon(args.after)
+          ? html`<leu-icon slot="after" name=${args.after}></leu-icon>`
+          : html`<span slot="after">${args.after}</span>`
+        : null}
     </leu-menu-item>
   `
 }
@@ -50,7 +55,7 @@ Active.args = {
 
 export const IconBefore = Template.bind({})
 IconBefore.args = {
-  before: "check",
+  before: "download",
 }
 
 export const IconAfterLink = Template.bind({})
@@ -69,3 +74,8 @@ export const IconPlaceholder = Template.bind({})
 IconPlaceholder.args = {
   before: "EMPTY",
 }
+
+export const MultipleSelection = Template.bind({})
+MultipleSelection.args = {
+  multipleSelection: true,
+}

src/components/menu/test/menu-item.test.js

@@ -15,6 +15,7 @@ async function defaultFixture(args = {}) {
       ?active=${args.active}
       ?disabled=${args.disabled}
       ?tabbable=${args.tabbable}
+      ?multipleSelection=${args.multipleSelection}
     >
       ${args.label}
     </leu-menu-item>
@@ -183,4 +184,26 @@ describe("LeuMenuItem", () => {
 
     expect(el.getValue()).to.equal("download-01")
   })
+
+  it("renders a palceholder icon when the menu item is part of multiple selection but not active", async () => {
+    const el = await defaultFixture({
+      label: "Download",
+      multipleSelection: true,
+    })
+
+    const icon = el.shadowRoot.querySelector("leu-icon")
+    expect(icon).to.exist
+    expect(icon).to.have.attribute("name", "EMPTY")
+  })
+
+  it("renders a check icon when the menu item is part of multiple selection and is active", async () => {
+    const el = await defaultFixture({
+      label: "Download",
+      multipleSelection: true,
+    })
+
+    const icon = el.shadowRoot.querySelector("leu-icon")
+    expect(icon).to.exist
+    expect(icon).to.have.attribute("name", "check")
+  })
 })

src/components/select/Select.js

@@ -146,11 +146,13 @@ export class LeuSelect extends LeuElement {
 
     if (
       changedProperties.has("value") ||
-      changedProperties.has("_optionFilter")
+      changedProperties.has("_optionFilter") ||
+      changedProperties.has("multiple")
     ) {
       this._updateMenuItems({
         value: changedProperties.has("value"),
         optionFilter: changedProperties.has("_optionFilter"),
+        multiple: changedProperties.has("multiple"),
       })
     }
   }
@@ -171,6 +173,10 @@ export class LeuSelect extends LeuElement {
 
     /* eslint-disable no-param-reassign */
     menuItems.forEach((menuItem) => {
+      if (changed.multiple) {
+        menuItem.multipleSelection = this.multiple
+      }
+
       if (changed.optionFilter) {
         menuItem.hidden =
           this._optionFilter !== "" &&

src/components/select/test/select.test.js

@@ -405,6 +405,21 @@ describe("LeuSelect", () => {
     expect(popup.active).to.not.be.true
   })
 
+  it("sets the multipleSelection property on the menu items when multiple selection is allowed", async () => {
+    const el = await defaultFixture({
+      options: MUNICIPALITIES,
+      label: "Gemeinde",
+      multiple: true,
+    })
+
+    const menuItems = Array.from(el.querySelectorAll("leu-menu-item"))
+    expect(menuItems.every((item) => item.multipleSelection)).to.be.true
+
+    el.multiple = false
+    await elementUpdated(el)
+
+    expect(menuItems.every((item) => !item.multipleSelection)).to.be.true
+
   it("closes the popup when the document is clicked outside the component", async () => {
     const el = await defaultFixture({
       options: MUNICIPALITIES,