Merge pull request #4072 from flypapertech/add-trailing-newline-when-saving-packagejson

feat(): Add trailing newline when saving package.json

Author: Dimitar Tachev

lib/common/declarations.d.ts

@@ -2011,3 +2011,13 @@ interface ILockFile {
 	 */
 	check(lockFilePath?: string, lockFileOpts?: ILockFileOptions): boolean;
 }
+
+declare module "stringify-package" {
+	function stringifyPackage(data: any, indent: any, newline: string): string
+	export = stringifyPackage
+}
+
+declare module "detect-newline" {
+	function detectNewline(data: string): string | null;
+	export = detectNewline
+}

lib/common/file-system.ts

@@ -5,6 +5,10 @@ import * as injector from "./yok";
 import * as crypto from "crypto";
 import * as shelljs from "shelljs";
 import { parseJson } from "./helpers";
+import { PACKAGE_JSON_FILE_NAME } from "../constants";
+import { EOL } from "os";
+import stringifyPackage = require("stringify-package");
+import detectNewline = require("detect-newline");
 
 // TODO: Add .d.ts for mkdirp module (or use it from @types repo).
 const mkdirp = require("mkdirp");
@@ -205,7 +209,19 @@ export class FileSystem implements IFileSystem {
 			space = this.getIndentationCharacter(filename);
 		}
 
-		return this.writeFile(filename, JSON.stringify(data, null, space), encoding);
+		let stringifiedData;
+		if (path.basename(filename) === PACKAGE_JSON_FILE_NAME) {
+			let newline = EOL;
+			if (fs.existsSync(filename)) {
+				const existingFile = this.readText(filename);
+				newline = detectNewline(existingFile);
+			}
+			stringifiedData = stringifyPackage(data, space, newline);
+		} else {
+			stringifiedData = JSON.stringify(data, null, space);
+		}
+
+		return this.writeFile(filename, stringifiedData, encoding);
 	}
 
 	public copyFile(sourceFileName: string, destinationFileName: string): void {

npm-shrinkwrap.json

@@ -37,6 +37,7 @@
     "cli-table": "https://github.com/telerik/cli-table/tarball/v0.3.1.2",
     "color": "3.0.0",
     "colors": "1.1.2",
+    "detect-newline": "2.1.0",
     "email-validator": "1.0.4",
     "esprima": "2.7.0",
     "gaze": "1.1.0",
@@ -73,6 +74,7 @@
     "shelljs": "0.7.6",
     "simple-plist": "0.2.1",
     "source-map": "0.5.6",
+    "stringify-package": "1.0.0",
     "tabtab": "https://github.com/Icenium/node-tabtab/tarball/master",
     "tar": "4.4.4",
     "temp": "0.8.3",