feat: add reporting for shadowSupportMode

packages/@lwc/engine-core/src/framework/def.ts

@@ -48,6 +48,7 @@ import {
     HTMLElementConstructor,
 } from './base-bridge-element';
 import { getComponentOrSwappedComponent } from './hot-swaps';
+import { isReportingEnabled, report, ReportingEventId } from './reporting';
 
 export interface ComponentDef {
     name: string;
@@ -198,6 +199,17 @@ function createComponentDef(Ctor: LightningElementConstructor): ComponentDef {
     let shadowSupportMode = superDef.shadowSupportMode;
     if (!isUndefined(ctorShadowSupportMode)) {
         shadowSupportMode = ctorShadowSupportMode;
+
+        if (
+            isReportingEnabled() &&
+            (shadowSupportMode === ShadowSupportMode.Any ||
+                shadowSupportMode === ShadowSupportMode.Native)
+        ) {
+            report(ReportingEventId.ShadowSupportModeUsage, {
+                tagName: Ctor.name,
+                mode: shadowSupportMode,
+            });
+        }
     }
 
     let renderMode = superDef.renderMode;

packages/@lwc/engine-core/src/framework/reporting.ts

@@ -6,7 +6,7 @@
  */
 import { noop } from '@lwc/shared';
 
-import { ShadowMode } from './vm';
+import { ShadowMode, ShadowSupportMode } from './vm';
 
 export const enum ReportingEventId {
     CrossRootAriaInSyntheticShadow = 'CrossRootAriaInSyntheticShadow',
@@ -16,6 +16,7 @@ export const enum ReportingEventId {
     StylesheetMutation = 'StylesheetMutation',
     ConnectedCallbackWhileDisconnected = 'ConnectedCallbackWhileDisconnected',
     ShadowModeUsage = 'ShadowModeUsage',
+    ShadowSupportModeUsage = 'ShadowSupportModeUsage',
 }
 
 export interface BasePayload {
@@ -51,6 +52,12 @@ export interface ShadowModeUsagePayload extends BasePayload {
     mode: ShadowMode;
 }
 
+// TODO [#3981]: Add schema to o11y schema repo so that we can use 'ctorName' or 'name'
+// instead of overloading 'tagName'.
+export interface ShadowSupportModeUsagePayload extends BasePayload {
+    mode: ShadowSupportMode;
+}
+
 export type ReportingPayloadMapping = {
     [ReportingEventId.CrossRootAriaInSyntheticShadow]: CrossRootAriaInSyntheticShadowPayload;
     [ReportingEventId.CompilerRuntimeVersionMismatch]: CompilerRuntimeVersionMismatchPayload;
@@ -59,6 +66,7 @@ export type ReportingPayloadMapping = {
     [ReportingEventId.StylesheetMutation]: StylesheetMutationPayload;
     [ReportingEventId.ConnectedCallbackWhileDisconnected]: ConnectedCallbackWhileDisconnectedPayload;
     [ReportingEventId.ShadowModeUsage]: ShadowModeUsagePayload;
+    [ReportingEventId.ShadowSupportModeUsage]: ShadowSupportModeUsagePayload;
 };
 
 export type ReportingDispatcher<T extends ReportingEventId = ReportingEventId> = (

packages/@lwc/integration-karma/test/mixed-shadow-mode/shadowSupportModeReporting/index.spec.js

@@ -0,0 +1,66 @@
+import { createElement } from 'lwc';
+import { attachReportingControlDispatcher, detachReportingControlDispatcher } from 'test-utils';
+
+import Any from 'x/any';
+import Reset from 'x/reset';
+import None from 'x/none';
+import NativeOnly from 'x/native';
+
+// Should be kept in sync with the enum in vm.ts
+const ShadowSupportMode = {
+    Any: 'any',
+    Default: 'reset',
+    Native: 'native',
+};
+
+/**
+ * These tests must be the first ones to generate the component def for the components they use.
+ * This is because subsequent calls to create the component will use the cached ctor rather than
+ * recreating the entire def. We only report on that initial def creation for perf reasons.
+ */
+describe('shadow support mode reporting', () => {
+    let dispatcher;
+
+    beforeEach(() => {
+        dispatcher = jasmine.createSpy();
+        attachReportingControlDispatcher(dispatcher, ['ShadowSupportModeUsage']);
+    });
+
+    afterEach(() => {
+        detachReportingControlDispatcher();
+    });
+
+    it('should report use of value "any"', () => {
+        expect(() => {
+            createElement('x-any', { is: Any });
+        }).toLogWarningDev(/Invalid value 'any' for static property shadowSupportMode/);
+
+        expect(dispatcher).toHaveBeenCalledTimes(1);
+        expect(dispatcher).toHaveBeenCalledWith('ShadowSupportModeUsage', {
+            tagName: Any.name,
+            mode: ShadowSupportMode.Any,
+        });
+    });
+
+    it('should report use of value "native"', () => {
+        createElement('x-native', { is: NativeOnly });
+
+        expect(dispatcher).toHaveBeenCalledTimes(1);
+        expect(dispatcher).toHaveBeenCalledWith('ShadowSupportModeUsage', {
+            tagName: NativeOnly.name,
+            mode: ShadowSupportMode.Native,
+        });
+    });
+
+    it('should not report use of value "reset"', () => {
+        createElement('x-reset', { is: Reset });
+
+        expect(dispatcher).toHaveBeenCalledTimes(0);
+    });
+
+    it('should not report when no value is provided', () => {
+        createElement('x-none', { is: None });
+
+        expect(dispatcher).toHaveBeenCalledTimes(0);
+    });
+});

packages/@lwc/integration-karma/test/mixed-shadow-mode/shadowSupportModeReporting/x/any/any.js

@@ -0,0 +1,5 @@
+import { LightningElement } from 'lwc';
+
+export default class Any extends LightningElement {
+    static shadowSupportMode = 'any';
+}

packages/@lwc/integration-karma/test/mixed-shadow-mode/shadowSupportModeReporting/x/native/native.js

@@ -0,0 +1,5 @@
+import { LightningElement } from 'lwc';
+
+export default class Native extends LightningElement {
+    static shadowSupportMode = 'native';
+}

packages/@lwc/integration-karma/test/mixed-shadow-mode/shadowSupportModeReporting/x/none/none.js

@@ -0,0 +1,3 @@
+import { LightningElement } from 'lwc';
+
+export default class None extends LightningElement {}

packages/@lwc/integration-karma/test/mixed-shadow-mode/shadowSupportModeReporting/x/reset/reset.js

@@ -0,0 +1,5 @@
+import { LightningElement } from 'lwc';
+
+export default class Reset extends LightningElement {
+    static shadowSupportMode = 'reset';
+}