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

[Logikgate]

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What is the current behavior?

Nativescript-CLI commands that save package.json are stripping the trailing newline that NPM inserts when saving package.json. This can cause un-needed commits of package.json where the only thing that has changed is the removal of the trailing newline.

What is the new behavior?

This pull request uses the module stringify-package, the same one used by NPM, to stringify package.json so that the formatting is kept the same. The method writeJSON now uses stringify-package only if it is saving a file named package.json.

Fixes/Implements/Closes #4049 .

[KristianDD]

Maybe this should be moved inside an else statement. No need to stringify data multiple times.

let stringifiedData;
if (path.basename(filename) === "package.json") {
	const newline = detectNewline(stringifiedData);
	stringifiedData = stringifyPackage(data, space, newline);
} else {
	stringifiedData = JSON.stringify(data, null, space);
}

[KristianDD]

package.json might be used from constants:

import { PACKAGE_JSON_FILE_NAME } from "../constants";

if (path.basename(filename) === PACKAGE_JSON_FILE_NAME ) {
...
}

[KristianDD]

It is safer to use an exact version. You can use npm i detect-newline --save-exact. Same goes for stringify-package dependency.

[radeva]

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