fix(radio-button, radio-button-group): prevent emitting events when selecting a checked radio button

packages/calcite-components/src/components/radio-button-group/radio-button-group.e2e.ts

@@ -458,15 +458,15 @@ describe("calcite-radio-button-group", () => {
     expect(changeEvent).toHaveReceivedEventTimes(0);
 
     await firstRadio.click();
-    expect(changeEvent).toHaveReceivedEventTimes(1);
+    expect(changeEvent).toHaveReceivedEventTimes(0);
     expect(await getSelectedItemValue()).toBe("one");
 
     await secondRadio.click();
-    expect(changeEvent).toHaveReceivedEventTimes(2);
+    expect(changeEvent).toHaveReceivedEventTimes(1);
     expect(await getSelectedItemValue()).toBe("two");
 
     await thirdRadio.click();
-    expect(changeEvent).toHaveReceivedEventTimes(3);
+    expect(changeEvent).toHaveReceivedEventTimes(2);
     expect(await getSelectedItemValue()).toBe("three");
   });
 

packages/calcite-components/src/components/radio-button/radio-button.e2e.ts

@@ -10,6 +10,7 @@ import {
   reflects,
   renders
 } from "../../tests/commonTests";
+import { html } from "../../../support/formatting";
 
 describe("calcite-radio-button", () => {
   describe("renders", () => {
@@ -184,6 +185,33 @@ describe("calcite-radio-button", () => {
     expect(value).toBe("1");
   });
 
+  it("should not emit calciteRadioButtonChange when checked already", async () => {
+    const page = await newE2EPage();
+    await page.setContent(html`<calcite-radio-button-group name="Options" layout="vertical">
+      <calcite-label layout="inline">
+        <calcite-radio-button checked value="trees"></calcite-radio-button>
+        Trees
+      </calcite-label>
+      <calcite-label layout="inline">
+        <calcite-radio-button value="layers" shrubs></calcite-radio-button>
+        Shrubs
+      </calcite-label>
+    </calcite-radio-button-group>`);
+
+    const checkedRadio = await page.find("calcite-radio-button[checked]");
+    expect(await checkedRadio.getProperty("checked")).toBe(true);
+
+    const changeEvent = await checkedRadio.spyOnEvent("calciteRadioButtonChange");
+
+    expect(changeEvent).toHaveReceivedEventTimes(0);
+
+    await checkedRadio.click();
+    await page.waitForChanges();
+    expect(await checkedRadio.getProperty("checked")).toBe(true);
+
+    expect(changeEvent).toHaveReceivedEventTimes(0);
+  });
+
   it("clicking a radio updates its checked status", async () => {
     const page = await newE2EPage();
     await page.setContent(`

packages/calcite-components/src/components/radio-button/radio-button.tsx

@@ -188,11 +188,17 @@ export class RadioButton
     if (this.disabled) {
       return;
     }
+
+    this.focused = true;
+    this.setFocus();
+
+    if (this.checked) {
+      return;
+    }
+
     this.uncheckAllRadioButtonsInGroup();
     this.checked = true;
-    this.focused = true;
     this.calciteRadioButtonChange.emit();
-    this.setFocus();
   };
 
   private clickHandler = (): void => {
@@ -204,25 +210,34 @@ export class RadioButton
   };
 
   onLabelClick(event: CustomEvent): void {
-    if (!this.disabled && !this.hidden) {
-      this.uncheckOtherRadioButtonsInGroup();
-      const label = event.currentTarget as HTMLCalciteLabelElement;
-      const radioButton = label.for
-        ? this.rootNode.querySelector<HTMLCalciteRadioButtonElement>(
-            `calcite-radio-button[id="${label.for}"]`
-          )
-        : label.querySelector<HTMLCalciteRadioButtonElement>(
-            `calcite-radio-button[name="${this.name}"]`
-          );
-
-      if (radioButton) {
-        radioButton.checked = true;
-        radioButton.focused = true;
-      }
+    if (this.disabled || this.hidden) {
+      return;
+    }
 
-      this.calciteRadioButtonChange.emit();
-      this.setFocus();
+    const label = event.currentTarget as HTMLCalciteLabelElement;
+
+    const radioButton = label.for
+      ? this.rootNode.querySelector<HTMLCalciteRadioButtonElement>(
+          `calcite-radio-button[id="${label.for}"]`
+        )
+      : label.querySelector<HTMLCalciteRadioButtonElement>(
+          `calcite-radio-button[name="${this.name}"]`
+        );
+
+    if (!radioButton) {
+      return;
+    }
+
+    radioButton.focused = true;
+    this.setFocus();
+
+    if (radioButton.checked) {
+      return;
     }
+
+    this.uncheckOtherRadioButtonsInGroup();
+    radioButton.checked = true;
+    this.calciteRadioButtonChange.emit();
   }
 
   private checkLastRadioButton(): void {