feature: @putout/operator-filesystem: getRootDirectory: add

Author: coderaiser

packages/operator-filesystem/README.md

@@ -140,6 +140,20 @@ dirPath === getParentDirectory(newDirectoryPath);
 true;
 ```
 
+### `getRootDirectory(path: FilePath | DirectoryPath): DrectoryPath`
+
+```js
+const {operator} = require('putout');
+const {
+    findFile,
+    getRootDirectory,
+} = operator;
+
+const [filePath] = findFile(ast, 'hello');
+
+getRootDirectory(dirPath);
+```
+
 ### `getFilename(path: FilePath | DirectoryPath): string`
 
 ```js

packages/operator-filesystem/lib/filesystem.js

@@ -399,22 +399,21 @@ module.exports.createNestedDirectory = (path, name) => {
     return lastDirectoryPath;
 };
 
+module.exports.getRootDirectory = getRootDirectory;
 function getRootDirectory(path) {
     let currentDirPath = getParentDirectory(path);
 
     if (!currentDirPath)
         return path;
 
-    let prevPath = path;
+    let prevPath = currentDirPath;
 
     while (currentDirPath = getParentDirectory(currentDirPath)) {
         prevPath = currentDirPath;
     }
 
     return prevPath;
-}
-
-module.exports.init = maybeFS.init;
+}module.exports.init = maybeFS.init;
 module.exports.deinit = maybeFS.deinit;
 
 module.exports.pause = maybeFS.pause;

packages/operator-filesystem/lib/filesystem.spec.js

@@ -27,6 +27,7 @@ const {
     createNestedDirectory,
     readDirectory,
     getParentDirectory,
+    getRootDirectory,
     readFileContent,
     writeFileContent,
     init,
@@ -1282,3 +1283,16 @@ test('putout: operator: filesystem: pause', (t) => {
     t.equal(pause, maybeFS.pause);
     t.end();
 });
+
+test('putout: operator: filesystem: getRootDirectory', (t) => {
+    const ast = parseFilesystem(['/hello/world/', '/hello/world/package.json']);
+    
+    const [filePath] = findFile(ast, 'package.json');
+    const rootDirectoryPath = getRootDirectory(filePath);
+    const filename = getFilename(rootDirectoryPath);
+    
+    const expected = '/hello/world';
+    
+    t.equal(filename, expected);
+    t.end();
+});