feat(@clack/prompts): add prompt workflow

Author: orochaa

examples/basic/package.json

@@ -13,7 +13,8 @@
     "stream": "jiti ./stream.ts",
     "spinner": "jiti ./spinner.ts",
     "spinner-ci": "npx cross-env CI=\"true\" jiti ./spinner-ci.ts",
-    "spinner-timer": "jiti ./spinner-timer.ts"
+    "spinner-timer": "jiti ./spinner-timer.ts",
+    "workflow": "jiti ./workflow.ts"
   },
   "devDependencies": {
     "jiti": "^1.17.0"

examples/basic/workflow.ts

@@ -0,0 +1,65 @@
+import * as p from '@clack/prompts';
+
+(async () => {
+	const results = await p
+		.workflow()
+		.step('name', () => p.text({ message: 'What is your package name?' }))
+		.step('type', () =>
+			p.select({
+				message: 'Pick a project type:',
+				initialValue: 'ts',
+				maxItems: 5,
+				options: [
+					{ value: 'ts', label: 'TypeScript' },
+					{ value: 'js', label: 'JavaScript' },
+					{ value: 'rust', label: 'Rust' },
+					{ value: 'go', label: 'Go' },
+					{ value: 'python', label: 'Python' },
+					{ value: 'coffee', label: 'CoffeeScript', hint: 'oh no' },
+				],
+			})
+		)
+		.step('install', () =>
+			p.confirm({
+				message: 'Install dependencies?',
+				initialValue: false,
+			})
+		)
+		.forkStep(
+			'fork',
+			({ results }) => results.install,
+			({ results }) => {
+				return p.workflow().step('package', () =>
+					p.select({
+						message: 'Pick a package manager:',
+						initialValue: 'pnpm',
+						options: [
+							{
+								label: 'npm',
+								value: 'npm',
+							},
+							{
+								label: 'yarn',
+								value: 'yarn',
+							},
+							{
+								label: 'pnpm',
+								value: 'pnpm',
+							},
+						],
+					})
+				);
+			}
+		)
+		.run();
+
+	await p
+		.workflow()
+		.step('cancel', () => p.text({ message: 'Try cancel prompt (Ctrl + C):' }))
+		.step('afterCancel', () => p.text({ message: 'This will not appear!' }))
+		.onCancel(({ results }) => {
+			p.cancel('Workflow canceled');
+			process.exit(0);
+		})
+		.run();
+})();

packages/prompts/README.md

@@ -159,6 +159,72 @@ const group = await p.group(
 console.log(group.name, group.age, group.color);
 ```
 
+### Workflow
+
+Works just like `group` but infer types way better and treats your group like a workflow, allowing you to create conditional steps (forks) along the process.
+
+```js
+import * as p from '@clack/prompts';
+
+const results = await p
+  .workflow()
+  .step('name', () => p.text({ message: 'What is your package name?' }))
+  .step('type', () =>
+    p.select({
+      message: `Pick a project type:`,
+      initialValue: 'ts',
+      maxItems: 5,
+      options: [
+        { value: 'ts', label: 'TypeScript' },
+        { value: 'js', label: 'JavaScript' },
+        { value: 'rust', label: 'Rust' },
+        { value: 'go', label: 'Go' },
+        { value: 'python', label: 'Python' },
+        { value: 'coffee', label: 'CoffeeScript', hint: 'oh no' },
+      ],
+    })
+  )
+  .step('install', () =>
+    p.confirm({
+      message: 'Install dependencies?',
+      initialValue: false,
+    })
+  )
+  .step('fork', ({ results }) => {
+    if (results.install === true) {
+      return p
+        .workflow()
+        .step('package', () =>
+          p.select({
+            message: 'Pick a package manager:',
+            initialValue: 'pnpm',
+            options: [
+              {
+                label: 'npm',
+                value: 'npm',
+              },
+              {
+                label: 'yarn',
+                value: 'yarn',
+              },
+              {
+                label: 'pnpm',
+                value: 'pnpm',
+              },
+            ],
+          })
+        )
+        .run();
+    }
+  })
+  .onCancel(() => {
+    p.cancel('Workflow canceled');
+    process.exit(0);
+  })
+  .run();
+console.log(results);
+```
+
 ### Tasks
 
 Execute multiple tasks in spinners.

packages/prompts/src/index.ts

@@ -844,36 +844,49 @@ export const spinner = ({ indicator = 'dots' }: SpinnerOptions = {}) => {
 	};
 };
 
-export type PromptGroupAwaitedReturn<T> = {
-	[P in keyof T]: Exclude<Awaited<T[P]>, symbol>;
+type Prettify<T> = {
+	[P in keyof T]: T[P];
+} & {};
+
+export type PromptAwaitedReturn<T> = Exclude<Awaited<T>, symbol>;
+
+export type PromptGroupAwaitedReturn<T> = Prettify<{
+	[P in keyof T]: PromptAwaitedReturn<T[P]>;
+}>;
+
+export type PromptWithOptions<
+	TResults,
+	TResult,
+	// biome-ignore lint/complexity/noBannedTypes: {} is initializing a empty object
+	TOptions extends Record<string, unknown> = {},
+> = (
+	opts: Prettify<
+		{
+			results: PromptGroupAwaitedReturn<TResults>;
+		} & TOptions
+	>
+) => TResult;
+
+export type PromptGroup<T> = {
+	[P in keyof T]: PromptWithOptions<Partial<Omit<T, P>>, undefined | Promise<T[P] | undefined>>;
 };
 
 export interface PromptGroupOptions<T> {
 	/**
 	 * Control how the group can be canceled
 	 * if one of the prompts is canceled.
 	 */
-	onCancel?: (opts: { results: Prettify<Partial<PromptGroupAwaitedReturn<T>>> }) => void;
+	onCancel?: PromptWithOptions<Partial<T>, void>;
 }
 
-type Prettify<T> = {
-	[P in keyof T]: T[P];
-} & {};
-
-export type PromptGroup<T> = {
-	[P in keyof T]: (opts: {
-		results: Prettify<Partial<PromptGroupAwaitedReturn<Omit<T, P>>>>;
-	}) => undefined | Promise<T[P] | undefined>;
-};
-
 /**
  * Define a group of prompts to be displayed
  * and return a results of objects within the group
  */
 export const group = async <T>(
 	prompts: PromptGroup<T>,
 	opts?: PromptGroupOptions<T>
-): Promise<Prettify<PromptGroupAwaitedReturn<T>>> => {
+): Promise<PromptGroupAwaitedReturn<T>> => {
 	const results = {} as any;
 	const promptNames = Object.keys(prompts);
 
@@ -898,6 +911,121 @@ export const group = async <T>(
 	return results;
 };
 
+type NextWorkflowBuilder<
+	TResults extends Record<string, unknown>,
+	TKey extends string,
+	TResult,
+> = WorkflowBuilder<
+	Prettify<
+		{
+			[Key in keyof TResults]: Key extends TKey ? TResult : TResults[Key];
+		} & {
+			[Key in TKey as undefined extends TResult ? never : TKey]: TResult;
+		} & {
+			[Key in TKey as undefined extends TResult ? TKey : never]?: TResult;
+		}
+	>
+>;
+
+type WorkflowStep<TName extends string, TResults, TResult = unknown> = {
+	name: TName;
+	prompt: PromptWithOptions<TResults, TResult>;
+	setResult: boolean;
+	condition?: PromptWithOptions<TResults, boolean>;
+};
+
+// biome-ignore lint/complexity/noBannedTypes: <explanation>
+class WorkflowBuilder<TResults extends Record<string, unknown> = {}> {
+	private results: TResults = {} as TResults;
+	private steps: WorkflowStep<string, TResults>[] = [];
+	private cancelCallback: PromptWithOptions<Partial<TResults>, void> | undefined;
+
+	public step<TName extends string, TResult>(
+		name: TName extends keyof TResults ? never : TName,
+		prompt: PromptWithOptions<TResults, TResult>
+	): NextWorkflowBuilder<TResults, TName, PromptAwaitedReturn<TResult>> {
+		this.steps.push({ name, prompt, setResult: true });
+		return this as any;
+	}
+
+	public conditionalStep<TName extends string, TResult>(
+		name: TName,
+		condition: PromptWithOptions<TResults, boolean>,
+		prompt: PromptWithOptions<TResults, TResult>
+	): NextWorkflowBuilder<
+		TResults,
+		TName,
+		| (TName extends keyof TResults ? TResults[TName] : never)
+		| PromptAwaitedReturn<TResult>
+		| undefined
+	> {
+		this.steps.push({ name, prompt, condition, setResult: true });
+		return this as any;
+	}
+
+	public forkStep<TName extends string, TResult extends Record<string, unknown>>(
+		name: TName,
+		condition: PromptWithOptions<TResults, boolean>,
+		subWorkflow: PromptWithOptions<TResults, WorkflowBuilder<TResult>>
+	): NextWorkflowBuilder<
+		TResults,
+		TName,
+		(TName extends keyof TResults ? TResults[TName] : never) | TResult | undefined
+	> {
+		this.steps.push({
+			name,
+			prompt: ({ results }) => {
+				return subWorkflow({ results }).run();
+			},
+			condition,
+			setResult: true,
+		});
+		return this as any;
+	}
+
+	public logStep(
+		name: string,
+		prompt: PromptWithOptions<TResults, void>
+	): WorkflowBuilder<TResults> {
+		this.steps.push({ name, prompt, setResult: false });
+		return this;
+	}
+
+	public customStep<TName extends string, TResult>(
+		step: WorkflowStep<TName, TResults, TResult>
+	): NextWorkflowBuilder<TResults, TName, PromptAwaitedReturn<TResult>> {
+		this.steps.push(step);
+		return this as any;
+	}
+
+	public onCancel(cb: PromptWithOptions<Partial<TResults>, void>): WorkflowBuilder<TResults> {
+		this.cancelCallback = cb;
+		return this;
+	}
+
+	public async run(): Promise<TResults> {
+		for (const step of this.steps) {
+			if (step.condition && !step.condition({ results: this.results as any })) {
+				continue;
+			}
+			const result = await step.prompt({ results: this.results as any });
+			if (isCancel(result)) {
+				this.cancelCallback?.({ results: this.results as any });
+				continue;
+			}
+			if (step.setResult) {
+				//@ts-ignore
+				this.results[step.name] = result;
+			}
+		}
+		return this.results;
+	}
+}
+
+export const workflow = () => {
+	return new WorkflowBuilder();
+};
+
 export type Task = {
 	/**
 	 * Task title