feat(commands): implement handleDeleteIdentity command (#239)

* feat(commands): implement handleDeleteIdentity command
Add delete identity functionality with UI and command handler:
- Add handleDeleteIdentity() in handlers.ts with vscodeLoader pattern
- Add showDeleteIdentityQuickPick() in identityPicker.ts for selection UI
- Add showErrorNotification() helper for consistent error display
- Register deleteIdentity command in extension.ts
- Migrate identity.ts to vscodeLoader pattern for E2E testability
- Add comprehensive E2E tests (17 test cases)

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Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Model-Raw: claude-opus-4-5-20251101

* refactor(identity): extract notification logic to reduce cognitive complexity
Extract showValidationErrorNotification() helper function from
getIdentitiesWithValidation() to reduce cognitive complexity from 16 to 12.
This satisfies SonarQube's maximum allowed complexity of 15.

🖥️ IDE: [Cursor](https://cursor.sh)
🔌 Extension: [Claude Code](https://claude.ai/download)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Model-Raw: claude-opus-4-5-20251101

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: nullvariant

extensions/git-id-switcher/src/commands/handlers.ts

@@ -10,8 +10,9 @@
  */
 
 import * as vscode from 'vscode';
-import { Identity, getIdentityLabel } from '../identity/identity';
-import { showIdentityQuickPick, showErrorNotification } from '../ui/identityPicker';
+import { getVSCode } from '../core/vscodeLoader';
+import { Identity, getIdentityLabel, deleteIdentityFromConfig } from '../identity/identity';
+import { showIdentityQuickPick, showDeleteIdentityQuickPick, showErrorNotification } from '../ui/identityPicker';
 import { requireWorkspaceTrust } from '../core/workspaceTrust';
 import { getUserSafeMessage, isFatalError } from '../core/errors';
 import { IdentityStatusBar } from '../ui/identityStatusBar';
@@ -105,3 +106,91 @@ export async function showWelcomeNotification(): Promise<void> {
     );
   }
 }
+
+/**
+ * Handle the delete identity command.
+ *
+ * Uses vscodeLoader for testability (allows mocking in E2E tests).
+ *
+ * Flow:
+ * 1. Show quick pick for selection (empty check handled by picker)
+ * 2. Check if selected identity is current
+ * 3. Show confirmation dialog (different message for current identity)
+ * 4. Delete identity from config
+ * 5. Clear workspace state if current identity was deleted
+ * 6. Update status bar
+ * 7. Show success notification
+ *
+ * @param context - VS Code extension context
+ * @param statusBar - Identity status bar instance for UI update
+ */
+export async function handleDeleteIdentity(
+  context: vscode.ExtensionContext,
+  statusBar: IdentityStatusBar
+): Promise<void> {
+  const vs = getVSCode();
+  if (!vs) {
+    return;
+  }
+
+  // SECURITY: Block command execution in untrusted workspaces
+  if (!requireWorkspaceTrust()) {
+    return;
+  }
+
+  // Get current identity ID from workspace state
+  const currentIdentityId = context.workspaceState.get<string>('currentIdentityId');
+
+  try {
+    // Show quick pick for selection
+    const selectedIdentity = await showDeleteIdentityQuickPick(currentIdentityId);
+
+    if (!selectedIdentity) {
+      // User cancelled
+      return;
+    }
+
+    const isCurrentIdentity = selectedIdentity.id === currentIdentityId;
+    const identityLabel = getIdentityLabel(selectedIdentity);
+
+    // Show confirmation dialog (different message for current identity)
+    const confirmMessage = isCurrentIdentity
+      ? vs.l10n.t("'{0}' is your current identity. Delete anyway?", identityLabel)
+      : vs.l10n.t("Are you sure you want to delete '{0}'?", identityLabel);
+
+    const deleteButton = vs.l10n.t('Delete');
+    const confirmation = await vs.window.showWarningMessage(
+      confirmMessage,
+      { modal: true },
+      deleteButton
+    );
+
+    if (confirmation !== deleteButton) {
+      // User cancelled confirmation
+      return;
+    }
+
+    // Delete identity from config
+    await deleteIdentityFromConfig(selectedIdentity.id);
+
+    // Clear workspace state and update status bar if current identity was deleted
+    if (isCurrentIdentity) {
+      await context.workspaceState.update('currentIdentityId', undefined);
+      statusBar.setNoIdentity();
+    }
+
+    // Show success notification
+    vs.window.showInformationMessage(
+      vs.l10n.t("Identity '{0}' has been deleted.", identityLabel)
+    );
+  } catch (error) {
+    // SECURITY: Use getUserSafeMessage to prevent information leakage
+    const safeMessage = getUserSafeMessage(error);
+    showErrorNotification(vs.l10n.t('Failed to delete identity: {0}', safeMessage));
+
+    // Propagate fatal errors (security violations)
+    if (isFatalError(error)) {
+      throw error;
+    }
+  }
+}

extensions/git-id-switcher/src/core/extension.ts

@@ -12,7 +12,7 @@ import { securityLogger } from '../security/securityLogger';
 import { getUserSafeMessage, isFatalError } from './errors';
 import { initializeWorkspaceTrust } from './workspaceTrust';
 import { tryRestoreSavedIdentity, tryDetectFromGit, tryDetectFromSsh, applyDetectedIdentity } from '../services/detection';
-import { selectIdentityCommand, showCurrentIdentityCommand, showWelcomeNotification } from '../commands/handlers';
+import { selectIdentityCommand, showCurrentIdentityCommand, showWelcomeNotification, handleDeleteIdentity } from '../commands/handlers';
 
 // Global state
 let statusBar: IdentityStatusBar;
@@ -48,7 +48,11 @@ export async function activate(context: vscode.ExtensionContext): Promise<void>
     'git-id-switcher.showDocumentation',
     () => showDocumentation(context)
   );
-  context.subscriptions.push(selectCommand, showCurrentCommand, showDocsCommand);
+  const deleteCommand = vscode.commands.registerCommand(
+    'git-id-switcher.deleteIdentity',
+    () => handleDeleteIdentity(context, statusBar)
+  );
+  context.subscriptions.push(selectCommand, showCurrentCommand, showDocsCommand, deleteCommand);
 
   // SECURITY: Check workspace trust before initializing sensitive operations
   const isTrusted = initializeWorkspaceTrust(context, async () => {

extensions/git-id-switcher/src/identity/identity.ts

@@ -3,9 +3,11 @@
  *
  * Identities are loaded from VS Code settings, not hardcoded.
  * Each identity represents a Git persona with optional SSH/GPG keys.
+ *
+ * Uses vscodeLoader for testability (allows mocking in E2E tests).
  */
 
-import * as vscode from 'vscode';
+import { getVSCode } from '../core/vscodeLoader';
 import { validateIdentitySchema } from './configSchema';
 import { securityLogger } from '../security/securityLogger';
 import { MAX_IDENTITIES, MAX_ID_LENGTH } from '../core/constants';
@@ -17,6 +19,50 @@ import { isValidIdentityId } from '../validators/common';
  */
 let hasShownValidationError = false;
 
+/**
+ * Show one-time validation error notification to user.
+ *
+ * Extracted from getIdentitiesWithValidation() to reduce cognitive complexity.
+ * Sets flag immediately to prevent concurrent notifications from race conditions.
+ *
+ * @param invalidCount - Number of invalid identity configurations
+ */
+function showValidationErrorNotification(invalidCount: number): void {
+  const vs = getVSCode();
+  if (!vs || hasShownValidationError) {
+    return;
+  }
+
+  // Set flag immediately to prevent concurrent notifications
+  hasShownValidationError = true;
+
+  const message = invalidCount === 1
+    ? vs.l10n.t(
+        'Git ID Switcher: 1 identity configuration is invalid and was skipped. Check the settings.'
+      )
+    : vs.l10n.t(
+        'Git ID Switcher: {0} identity configurations are invalid and were skipped. Check the settings.',
+        invalidCount
+      );
+
+  // Fire and forget: notification is non-blocking
+  // Note: VS Code's Thenable doesn't have .catch(), so we use .then(onFulfilled, onRejected)
+  vs.window.showWarningMessage(message, vs.l10n.t('Open Settings'))
+    .then(
+      action => {
+        if (action) {
+          vs.commands.executeCommand(
+            'workbench.action.openSettings',
+            'gitIdSwitcher.identities'
+          );
+        }
+      },
+      () => {
+        // SECURITY: Don't let notification errors affect validation flow
+      }
+    );
+}
+
 export interface Identity {
   /** Unique identifier (lowercase, no spaces) */
   id: string;
@@ -53,7 +99,11 @@ export interface Identity {
  * Use getIdentitiesWithValidation() for security-critical code paths.
  */
 export function getIdentities(): Identity[] {
-  const config = vscode.workspace.getConfiguration('gitIdSwitcher');
+  const vs = getVSCode();
+  if (!vs) {
+    return [];
+  }
+  const config = vs.workspace.getConfiguration('gitIdSwitcher');
   const identities = config.get<Identity[]>('identities', []);
   return identities;
 }
@@ -67,7 +117,12 @@ export function getIdentities(): Identity[] {
  * @returns Array of valid identities (invalid ones are filtered out)
  */
 export function getIdentitiesWithValidation(): Identity[] {
-  const config = vscode.workspace.getConfiguration('gitIdSwitcher');
+  const vs = getVSCode();
+  if (!vs) {
+    return [];
+  }
+
+  const config = vs.workspace.getConfiguration('gitIdSwitcher');
   const rawIdentities = config.get<unknown[]>('identities', []);
 
   // Type check: must be an array
@@ -141,39 +196,8 @@ export function getIdentitiesWithValidation(): Identity[] {
   }
 
   // Show one-time notification if there are invalid identities
-  // SECURITY: Set flag before async operation to prevent race conditions
-  // Multiple concurrent validations won't trigger duplicate notifications
-  if (invalidIndices.length > 0 && !hasShownValidationError) {
-    // Set flag immediately to prevent concurrent notifications
-    hasShownValidationError = true;
-
-    const message = invalidIndices.length === 1
-      ? vscode.l10n.t(
-          'Git ID Switcher: 1 identity configuration is invalid and was skipped. Check the settings.'
-        )
-      : vscode.l10n.t(
-          'Git ID Switcher: {0} identity configurations are invalid and were skipped. Check the settings.',
-          invalidIndices.length
-        );
-
-    // Fire and forget: notification is non-blocking
-    // User can dismiss or open settings as needed
-    // Note: VS Code's Thenable doesn't have .catch(), so we use .then(onFulfilled, onRejected)
-    vscode.window.showWarningMessage(message, vscode.l10n.t('Open Settings'))
-      .then(
-        action => {
-          if (action) {
-            vscode.commands.executeCommand(
-              'workbench.action.openSettings',
-              'gitIdSwitcher.identities'
-            );
-          }
-        },
-        () => {
-          // SECURITY: Don't let notification errors affect validation flow
-          // Silently ignore notification errors
-        }
-      );
+  if (invalidIndices.length > 0) {
+    showValidationErrorNotification(invalidIndices.length);
   }
 
   return validIdentities;
@@ -201,7 +225,12 @@ export function getIdentityById(id: string): Identity | undefined {
  * Uses validated identities to ensure only valid identities are returned.
  */
 export function getDefaultIdentity(): Identity | undefined {
-  const config = vscode.workspace.getConfiguration('gitIdSwitcher');
+  const vs = getVSCode();
+  if (!vs) {
+    return undefined;
+  }
+
+  const config = vs.workspace.getConfiguration('gitIdSwitcher');
   const defaultId = config.get<string>('defaultIdentity', '');
 
   const identities = getIdentitiesWithValidation();
@@ -263,17 +292,23 @@ export function formatGitAuthor(identity: Identity): string {
  * @throws Error if identity ID format is invalid
  * @throws Error if identity with given ID is not found
  * @throws Error if configuration update fails
+ * @throws Error if VS Code API is not available
  *
  * @example
  * await deleteIdentityFromConfig('work-github');
  */
 export async function deleteIdentityFromConfig(id: string): Promise<void> {
+  const vs = getVSCode();
+  if (!vs) {
+    throw new Error('VS Code API not available');
+  }
+
   // Validate ID format
   if (!isValidIdentityId(id, MAX_ID_LENGTH)) {
     throw new Error(`Invalid identity ID format: ${id}`);
   }
 
-  const config = vscode.workspace.getConfiguration('gitIdSwitcher');
+  const config = vs.workspace.getConfiguration('gitIdSwitcher');
   const identities = config.get<Identity[]>('identities', []);
 
   // Find the identity to delete
@@ -286,7 +321,7 @@ export async function deleteIdentityFromConfig(id: string): Promise<void> {
   const updatedIdentities = identities.filter(i => i.id !== id);
 
   // Update configuration
-  await config.update('identities', updatedIdentities, vscode.ConfigurationTarget.Global);
+  await config.update('identities', updatedIdentities, vs.ConfigurationTarget.Global);
 
   // Log security event
   securityLogger.logConfigChange('identities');