feat(ui5-shellbar) support self-collapsible search (#11296)

This PR updates the ShellBar search functionality to support two separate collapse modes for search fields.

### Changes
**Dual Mode Support**:
Allows self-collapsible search with an internal toggle and collapsed property or fully custom search with its own button.

**Syncing Mechanism**:
The two collapse mechanisms are now synchronized using the showSearchField getter/setter instead of a combined property.

**Customization Options**:
New properties `hideSearchButton` and `disableAutoSearchField` enable further customization of custom search fields.

**Accessibility Improvements**:
Roles and labels are correctly set for the content items container.

**New Features**:
A new `search-field-toggle` event is fired when the search field is toggled by internal rules, and a new getter `searchButtonRef` is available for managing focus on the search button.

Author: dobrinyonkov

packages/fiori/cypress/specs/ShellBar.cy.tsx

@@ -11,6 +11,7 @@ import ToggleButton from "@ui5/webcomponents/dist/ToggleButton.js";
 import ListItemStandard from "@ui5/webcomponents/dist/ListItemStandard.js";
 import Avatar from "@ui5/webcomponents/dist/Avatar.js";
 import Switch from "@ui5/webcomponents/dist/Switch.js";
+import Search from "../../src/Search.js";
 
 const RESIZE_THROTTLE_RATE = 300; // ms
 
@@ -324,13 +325,13 @@ describe("Slots", () => {
 			function assertStartSeparatorVisibility(expectedExist: boolean) {
 				cy.get("#shellbar")
 					.shadow()
-					.find(".ui5-shellbar-overflow-container-right-inner > .ui5-shellbar-separator-start")
+					.find(".ui5-shellbar-content-items > .ui5-shellbar-separator-start")
 					.should(expectedExist ? "exist" : "not.exist");
 			}
 			function assertEndSeparatorVisibility(expectedExist: boolean) {
 				cy.get("#shellbar")
 					.shadow()
-					.find(".ui5-shellbar-overflow-container-right-inner > .ui5-shellbar-separator-end")
+					.find(".ui5-shellbar-content-items > .ui5-shellbar-separator-end")
 					.should(expectedExist ? "exist" : "not.exist");
 			}
 
@@ -390,4 +391,136 @@ describe("Slots", () => {
 				.should("not.exist");
 		});
 	});
+
+	describe("Search field slot", () => {
+		it("Test search button is not visible when the search field slot is empty", () => {
+			cy.mount(
+				<ShellBar id="shellbar"></ShellBar>
+			);
+			cy.get("#shellbar")
+				.shadow()
+				.find(".ui5-shellbar-search-button")
+				.should("not.exist");
+		});
+
+		it("Test search button is visible when the search field slot is not empty", () => {
+			cy.mount(
+				<ShellBar id="shellbar">
+					<Input slot="searchField"></Input>
+				</ShellBar>
+			);
+			cy.get("#shellbar")
+				.shadow()
+				.find(".ui5-shellbar-search-button")
+				.should("exist");
+		});
+
+		it("Test search button is not visible when the hide-search-button property is set to true", () => {
+			cy.mount(
+				<ShellBar id="shellbar" hideSearchButton={true}>
+					<Input slot="searchField"></Input>
+				</ShellBar>
+			);
+			cy.get("#shellbar")
+				.shadow()
+				.find(".ui5-shellbar-search-button")
+				.should("not.exist");
+		});
+
+		it("Test search field is collapsed by default and expanded on click", () => {
+			cy.mount(
+				<ShellBar id="shellbar">
+					<Input slot="searchField"></Input>
+				</ShellBar>
+			);
+			cy.get("#shellbar").shadow().as("shellbar");
+			cy.get("@shellbar").find(".ui5-shellbar-search-field").should("not.exist");
+			cy.get("@shellbar").find(".ui5-shellbar-search-button").click();
+			cy.get("@shellbar").find(".ui5-shellbar-search-field").should("exist");
+		});
+
+		it("Test search field is expanded by default when show-search-field is set to true", () => {
+			cy.mount(
+				<ShellBar id="shellbar" showSearchField={true}>
+					<Input slot="searchField"></Input>
+				</ShellBar>
+			);
+			cy.get("#shellbar")
+				.shadow()
+				.find(".ui5-shellbar-search-field")
+				.should("exist");
+		});
+
+		it("Test search button is not visible when a self-collapsible search field slot is empty", () => {
+			cy.mount(
+				<ShellBar id="shellbar">
+					<Search slot="searchField"></Search>
+				</ShellBar>
+			);
+			cy.get("#shellbar")
+				.shadow()
+				.find(".ui5-shellbar-search-button")
+				.should("not.exist");
+		});
+
+		it("Test self-collapsible search is expanded and collapsed by the show-search-field property", () => {
+			cy.mount(
+				<ShellBar id="shellbar" showSearchField={true}>
+					<Search id="search" slot="searchField"></Search>
+				</ShellBar>
+			);
+			cy.get("#search").should("have.prop", "collapsed", false);
+			cy.get("#shellbar").invoke("prop", "showSearchField", false);
+			cy.get("#search").should("have.prop", "collapsed", true);
+		});
+
+
+		it("Test showSearchField property is true when using expanded search field", () => {
+			cy.mount(
+				<ShellBar id="shellbar">
+					<Search id="search" slot="searchField"></Search>
+				</ShellBar>
+			);
+			cy.get("#search").should("have.prop", "collapsed", false);
+			cy.get("#shellbar").invoke("prop", "showSearchField").should("equal", true);
+		});
+
+		it("Test showSearchField property is false when using collapsed search field", () => {
+			cy.mount(
+				<ShellBar id="shellbar">
+					<Search id="search" slot="searchField" collapsed></Search>
+				</ShellBar>
+			);
+			cy.get("#search").should("have.prop", "collapsed", true);
+			cy.get("#shellbar").invoke("prop", "showSearchField").should("equal", false);
+		});
+	});
 });
+
+describe("Events", () => {
+	it("Test click on the search button fires search-button-click event", () => {
+		cy.mount(
+			<ShellBar>
+				<Input slot="searchField"></Input>
+			</ShellBar>
+		);
+		cy.get("[ui5-shellbar")
+			.as("shellbar");
+
+		cy.get("@shellbar")
+			.then(shellbar => {
+				shellbar.get(0).addEventListener("ui5-search-button-click", cy.stub().as("searchButtonClick"));
+			});
+
+		cy.get("@shellbar")
+			.shadow()
+			.find(".ui5-shellbar-search-button")
+			.as("searchButton");
+		
+		cy.get("@searchButton")
+			.click();
+
+		cy.get("@searchButtonClick")
+			.should("have.been.calledOnce");
+	});
+});