feat: support [contenthash]

Author: alexander-akait

README.md

@@ -164,20 +164,31 @@ The following tokens are replaced in the `name` parameter:
 * `[folder]` the folder of the resource is in.
 * `[emoji]` a random emoji representation of `options.content`
 * `[emoji:<length>]` same as above, but with a customizable number of emojis
+* `[contenthash]` the hash of `options.content` (Buffer) (by default it's the hex digest of the md5 hash)
+* `[<hashType>:contenthash:<digestType>:<length>]` optionally one can configure
+  * other `hashType`s, i. e. `sha1`, `md5`, `sha256`, `sha512`
+  * other `digestType`s, i. e. `hex`, `base26`, `base32`, `base36`, `base49`, `base52`, `base58`, `base62`, `base64`
+  * and `length` the length in chars
 * `[hash]` the hash of `options.content` (Buffer) (by default it's the hex digest of the md5 hash)
 * `[<hashType>:hash:<digestType>:<length>]` optionally one can configure
   * other `hashType`s, i. e. `sha1`, `md5`, `sha256`, `sha512`
   * other `digestType`s, i. e. `hex`, `base26`, `base32`, `base36`, `base49`, `base52`, `base58`, `base62`, `base64`
   * and `length` the length in chars
 * `[N]` the N-th match obtained from matching the current file name against `options.regExp`
 
+In loader context `[hash]` and `[contenthash]` are the same, but we recommend using `[contenthash]` for avoid misleading.
+
 Examples
 
 ``` javascript
 // loaderContext.resourcePath = "/app/js/javascript.js"
 loaderUtils.interpolateName(loaderContext, "js/[hash].script.[ext]", { content: ... });
 // => js/9473fdd0d880a43c21b7778d34872157.script.js
 
+// loaderContext.resourcePath = "/app/js/javascript.js"
+loaderUtils.interpolateName(loaderContext, "js/[contenthash].script.[ext]", { content: ... });
+// => js/9473fdd0d880a43c21b7778d34872157.script.js
+
 // loaderContext.resourcePath = "/app/page.html"
 loaderUtils.interpolateName(loaderContext, "html-[hash:6].html", { content: ... });
 // => html-9473fd.html

lib/interpolateName.js

@@ -67,8 +67,10 @@ function interpolateName(loaderContext, name, options) {
 	if(content) {
 		// Match hash template
 		url = url
+			// `hash` and `contenthash` are same in `loader-utils` context
+			// let's keep `hash` for backward compatibility
 			.replace(
-				/\[(?:([^:]+):)?hash(?::([a-z]+\d*))?(?::(\d+))?\]/ig,
+				/\[(?:([^:]+):)?(?:hash||contenthash)(?::([a-z]+\d*))?(?::(\d+))?\]/ig,
 				(all, hashType, digestType, maxLength) => getHashDigest(content, hashType, digestType, parseInt(maxLength, 10))
 			)
 			.replace(

test/interpolateName.test.js

@@ -24,10 +24,15 @@ describe("interpolateName()", () => {
 
 	[
 		["/app/js/javascript.js", "js/[hash].script.[ext]", "test content", "js/9473fdd0d880a43c21b7778d34872157.script.js"],
+		["/app/js/javascript.js", "js/[contenthash].script.[ext]", "test content", "js/9473fdd0d880a43c21b7778d34872157.script.js"],
 		["/app/page.html", "html-[hash:6].html", "test content", "html-9473fd.html"],
+		["/app/page.html", "html-[contenthash:6].html", "test content", "html-9473fd.html"],
 		["/app/flash.txt", "[hash]", "test content", "9473fdd0d880a43c21b7778d34872157"],
+		["/app/flash.txt", "[contenthash]", "test content", "9473fdd0d880a43c21b7778d34872157"],
 		["/app/img/image.png", "[sha512:hash:base64:7].[ext]", "test content", "2BKDTjl.png"],
+		["/app/img/image.png", "[sha512:contenthash:base64:7].[ext]", "test content", "2BKDTjl.png"],
 		["/app/dir/file.png", "[path][name].[ext]?[hash]", "test content", "/app/dir/file.png?9473fdd0d880a43c21b7778d34872157"],
+		["/app/dir/file.png", "[path][name].[ext]?[contenthash]", "test content", "/app/dir/file.png?9473fdd0d880a43c21b7778d34872157"],
 		["/vendor/test/images/loading.gif", path => path.replace(/\/?vendor\/?/, ""), "test content", "test/images/loading.gif"],
 		["/pathWith.period/filename.js", "js/[name].[ext]", "test content", "js/filename.js"],
 		["/pathWith.period/filenameWithoutExt", "js/[name].[ext]", "test content", "js/filenameWithoutExt.bin"]