feat(dev-infra): create a wizard for building commit messages (#38457)

Creates a wizard to walk through creating a commit message in the correct
template for commit messages in Angular repositories.

PR Close #38457

dev-infra/commit-message/builder.ts

@@ -0,0 +1,70 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import {ListChoiceOptions} from 'inquirer';
+
+import {info, promptAutocomplete, promptInput} from '../utils/console';
+
+import {COMMIT_TYPES, CommitType, getCommitMessageConfig, ScopeRequirement} from './config';
+
+/** Validate commit message at the provided file path. */
+export async function buildCommitMessage() {
+  // TODO(josephperrott): Add support for skipping wizard with local untracked config file
+  // TODO(josephperrott): Add default commit message information/commenting into generated messages
+  info('Just a few questions to start building the commit message!');
+
+  /** The commit message type. */
+  const type = await promptForCommitMessageType();
+  /** The commit message scope. */
+  const scope = await promptForCommitMessageScopeForType(type);
+  /** The commit message summary. */
+  const summary = await promptForCommitMessageSummary();
+
+  return `${type.name}${scope ? '(' + scope + ')' : ''}: ${summary}\n\n`;
+}
+
+/** Prompts in the terminal for the commit message's type. */
+async function promptForCommitMessageType(): Promise<CommitType> {
+  info('The type of change in the commit. Allows a reader to know the effect of the change,');
+  info('whether it brings a new feature, adds additional testing, documents the `project, etc.');
+
+  /** List of commit type options for the autocomplete prompt. */
+  const typeOptions: ListChoiceOptions[] =
+      Object.values(COMMIT_TYPES).map(({description, name}) => {
+        return {
+          name: `${name} - ${description}`,
+          value: name,
+          short: name,
+        };
+      });
+  /** The key of a commit message type, selected by the user via prompt. */
+  const typeName = await promptAutocomplete('Select a type for the commit:', typeOptions);
+
+  return COMMIT_TYPES[typeName];
+}
+
+/** Prompts in the terminal for the commit message's scope. */
+async function promptForCommitMessageScopeForType(type: CommitType): Promise<string|false> {
+  // If the commit type's scope requirement is forbidden, return early.
+  if (type.scope === ScopeRequirement.Forbidden) {
+    info(`Skipping scope selection as the '${type.name}' type does not allow scopes`);
+    return false;
+  }
+  /** Commit message configuration */
+  const config = getCommitMessageConfig();
+
+  info('The area of the repository the changes in this commit most affects.');
+  return await promptAutocomplete(
+      'Select a scope for the commit:', config.commitMessage.scopes,
+      type.scope === ScopeRequirement.Optional ? '<no scope>' : '');
+}
+
+/** Prompts in the terminal for the commit message's summary. */
+async function promptForCommitMessageSummary(): Promise<string> {
+  info('Provide a short summary of what the changes in the commit do');
+  return await promptInput('Provide a short summary of the commit');
+}