Add support for Asar

core.d.ts

@@ -135,7 +135,8 @@ declare namespace core {
 		| 'avif'
 		| 'eps'
 		| 'lzh'
-		| 'pgp';
+		| 'pgp'
+		| 'asar';
 
 	type MimeType =
 		| 'image/jpeg'
@@ -262,7 +263,8 @@ declare namespace core {
 		| 'application/vnd.sketchup.skp'
 		| 'image/avif'
 		| 'application/x-lzh-compressed'
-		| 'application/pgp-encrypted';
+		| 'application/pgp-encrypted'
+		| 'application/asar';
 
 	interface FileTypeResult {
 		/**

core.js

@@ -1355,6 +1355,24 @@ async function _fromTokenizer(tokenizer) {
 			}
 		}
 	}
+
+	// Check for Asar
+	try {
+		// Check header_size
+		buffer.readUInt32LE(4);
+
+		// Check header
+		// Header's first char should be "{" because expect JSON
+		if (check([0x7B], {offset: 16})) {
+			const jsonSize = buffer.readUInt32LE(12);
+			const header = buffer.slice(16, jsonSize + 16).toString();
+			JSON.parse(header);
+			return {
+				ext: 'asar',
+				mime: 'application/asar'
+			};
+		}
+	} catch (_) {}
 }
 
 const stream = readableStream => new Promise((resolve, reject) => {

package.json

@@ -178,7 +178,8 @@
 		"avif",
 		"eps",
 		"lzh",
-		"pgp"
+		"pgp",
+	  	"asar"
 	],
 	"devDependencies": {
 		"@types/node": "^13.1.4",

readme.md

@@ -402,6 +402,7 @@ Returns a set of supported MIME types.
 - [`eps`](https://en.wikipedia.org/wiki/Encapsulated_PostScript) - Encapsulated PostScript
 - [`lzh`](https://en.wikipedia.org/wiki/LHA_(file_format)) - LZH archive
 - [`pgp`](https://en.wikipedia.org/wiki/Pretty_Good_Privacy) - Pretty Good Privacy
+- [`asar`](https://github.com/electron/asar#format) - Asar
 
 *Pull requests are welcome for additional commonly used file types.*
 

supported.js

@@ -133,7 +133,8 @@ module.exports = {
 		'avif',
 		'eps',
 		'lzh',
-		'pgp'
+		'pgp',
+		'asar'
 	],
 	mimeTypes: [
 		'image/jpeg',
@@ -260,6 +261,7 @@ module.exports = {
 		'application/vnd.sketchup.skp',
 		'image/avif',
 		'application/x-lzh-compressed',
-		'application/pgp-encrypted'
+		'application/pgp-encrypted',
+		'application/asar'
 	]
 };

test.js

@@ -22,6 +22,10 @@ const names = {
 		'fixture-adts-mpeg4-2',
 		'fixture-id3v2'
 	],
+	asar: [
+		'fixture',
+		'fixture2'
+	],
 	arw: [
 		'fixture',
 		'fixture2',