Support progressive reporting

index.d.ts

@@ -1,6 +1,22 @@
 import {GlobbyOptions} from 'globby';
 
 declare namespace del {
+	interface ProgressData {
+		/**
+		Deleted file count.
+		*/
+		deletedFiles: number;
+
+		/**
+		Overall file count.
+		*/
+		totalFiles: number;
+
+		/**
+		Completed percentage. A value between `0` and `1`.
+		*/
+		percent: number;
+	}
 	interface Options extends GlobbyOptions {
 		/**
 		Allow deleting the current working directory and outside.
@@ -33,6 +49,22 @@ declare namespace del {
 		@default Infinity
 		*/
 		readonly concurrency?: number;
+
+		/**
+		Callback function for progress reporting.
+
+		Called before each file is deleted.
+
+		@example
+		```js
+		import del from 'del';
+
+		await del(patterns, {onProgress: (progress) => {
+			// …
+		}});
+		```
+		*/
+		readonly onProgress?: (progress: ProgressData) => void;
 	}
 }
 

index.js

@@ -52,7 +52,7 @@ function normalizePatterns(patterns) {
 	return patterns;
 }
 
-module.exports = async (patterns, {force, dryRun, cwd = process.cwd(), ...options} = {}) => {
+module.exports = async (patterns, {force, dryRun, cwd = process.cwd(), onProgress = () => {}, ...options} = {}) => {
 	options = {
 		expandDirectories: false,
 		onlyFiles: false,
@@ -66,13 +66,27 @@ module.exports = async (patterns, {force, dryRun, cwd = process.cwd(), ...option
 	const files = (await globby(patterns, options))
 		.sort((a, b) => b.localeCompare(a));
 
-	const mapper = async file => {
+	if (files.length === 0) {
+		onProgress({
+			totalFiles: 0,
+			deletedFiles: 0,
+			percent: 1
+		});
+	}
+
+	const mapper = async (file, fileIndex) => {
 		file = path.resolve(cwd, file);
 
 		if (!force) {
 			safeCheck(file, cwd);
 		}
 
+		onProgress({
+			totalFiles: files.length,
+			deletedFiles: fileIndex,
+			percent: fileIndex / files.length
+		});
+
 		if (!dryRun) {
 			await rimrafP(file, rimrafOptions);
 		}
@@ -82,6 +96,12 @@ module.exports = async (patterns, {force, dryRun, cwd = process.cwd(), ...option
 
 	const removedFiles = await pMap(files, mapper, options);
 
+	onProgress({
+		totalFiles: files.length,
+		deletedFiles: files.length,
+		percent: 1
+	});
+
 	removedFiles.sort((a, b) => a.localeCompare(b));
 
 	return removedFiles;

readme.md

@@ -108,6 +108,34 @@ Minimum: `1`
 
 Concurrency limit.
 
+##### onProgress
+
+Type: `(progress: ProgressData) => void`
+
+Callback function for progress reporting.
+
+Called before each file is deleted.
+
+```js
+import del from 'del';
+
+await del(patterns, {onProgress: (progress) => {
+	// …
+}});
+```
+
+###### ProgressData
+
+```js
+{
+	totalFiles: number,
+	deletedFiles: number,
+	percent: number
+}
+```
+
+- `percent` is a value between `0` and `1`
+
 ## CLI
 
 See [del-cli](https://github.com/sindresorhus/del-cli) for a CLI for this module and [trash-cli](https://github.com/sindresorhus/trash-cli) for a safe version that is suitable for running by hand.

test.js

@@ -349,3 +349,47 @@ test('windows can pass relative paths with "\\" - sync', t => {
 
 	t.deepEqual(removeFiles, [nestedFile]);
 });
+
+test('report delete progress of non-existent file', async t => {
+	let report;
+
+	await del('non-existent-directory', {onProgress: event => {
+		report = event;
+	}});
+
+	t.deepEqual(report, {
+		totalFiles: 0,
+		deletedFiles: 0,
+		percent: 1
+	});
+});
+
+test('report delete progress of single file', async t => {
+	let report;
+
+	await del(t.context.tmp, {cwd: __dirname, force: true, onProgress: event => {
+		report = event;
+	}});
+
+	t.deepEqual(report, {
+		totalFiles: 1,
+		deletedFiles: 1,
+		percent: 1
+	});
+});
+
+test('report delete progress of multiple files', async t => {
+	let report;
+
+	const sourcePath = process.platform === 'win32' ? path.resolve(`${t.context.tmp}/*`).replace(/\\/g, '/') : `${t.context.tmp}/*`;
+
+	await del(sourcePath, {cwd: __dirname, force: true, onProgress: event => {
+		report = event;
+	}});
+
+	t.deepEqual(report, {
+		totalFiles: 4,
+		deletedFiles: 4,
+		percent: 1
+	});
+});