Merge pull request #18 from blackflux/dev

[Gally]: master <- dev

README.md

@@ -17,7 +17,14 @@ Abstraction Layer for File Management.
 
 ## Functions
 
-To ignore file extension and force treat the file as a certain type, you can pass the option `treatAs` as e.g. `json`.
+### guessFile(filepath)
+
+Extends and returns filepath with the file extension as appropriate. Returns `null` if no good match was found.
+
+A few notes:
+  - Only extends extensions, not partial file names
+  - Will prefer to match the exact file
+  - Will return `null` when multiple possible extensions are found
 
 ### smartRead(filepath, options = { treatAs = null })
 
@@ -32,6 +39,8 @@ The following extensions are handled in order:
 
 Note that the [required cache](https://nodejs.org/api/modules.html#modules_require_cache) is not automatically invalidated when loading cached `.js` files.
 
+To ignore file extension and force treat the file as a certain type, you can pass the option `treatAs` as e.g. `json`.
+
 ### smartWrite(filepath. content, options = { treatAs = null, mergeStrategy = (existing, changeset) => changeset })
 
 Serialize and write content to file based on file extension.
@@ -47,6 +56,8 @@ The following extension are handled in order:
 - `.yml` and `.yaml`: Serialize uses [yaml-boost](https://github.com/blackflux/yaml-boost).
 - `.*`: Expects content as array and serializes by joining array using new line character.
 
+To ignore file extension and force treat the file as a certain type, you can pass the option `treatAs` as e.g. `json`.
+
 The `mergeStrategy` option can be used to customize how the new content is merged if the target file already exists.
 By default the file is simply overwritten.
 

src/index.js

@@ -1,3 +1,5 @@
 
+module.exports.guessFile = require('./logic/guess-file');
+
 module.exports.smartRead = require('./logic/smart-read');
 module.exports.smartWrite = require('./logic/smart-write');

src/logic/guess-file.js

@@ -0,0 +1,17 @@
+const fs = require('fs');
+const path = require('path');
+
+module.exports = (filepath) => {
+  const dirname = path.dirname(filepath);
+  const basename = path.basename(filepath);
+  const relevantFiles = fs
+    .readdirSync(dirname)
+    .filter(f => f === basename || f.startsWith(`${basename}.`));
+  if (relevantFiles.includes(basename)) {
+    return filepath;
+  }
+  if (relevantFiles.length === 1) {
+    return path.join(dirname, relevantFiles[0]);
+  }
+  return null;
+};

test/index.spec.js

@@ -4,6 +4,6 @@ const sfs = require('../src/index');
 
 describe('Testing Integration', () => {
   it('Testing Exported Functions', () => {
-    expect(Object.keys(sfs)).to.deep.equal(['smartRead', 'smartWrite']);
+    expect(Object.keys(sfs)).to.deep.equal(['guessFile', 'smartRead', 'smartWrite']);
   });
 });

test/logic/guess-file.spec.js

@@ -0,0 +1,37 @@
+const fs = require('fs');
+const path = require('path');
+const expect = require('chai').expect;
+const tmp = require('tmp');
+const guessFile = require('../../src/logic/guess-file');
+
+describe('Testing guessFile', () => {
+  let dir;
+  beforeEach(() => {
+    dir = tmp.dirSync({ keep: false, unsafeCleanup: true }).name;
+  });
+
+  const executeTest = (files, input, expected) => {
+    files.forEach(f => fs.writeFileSync(path.join(dir, f), ''));
+    const filepath = path.join(dir, input);
+    expect(guessFile(filepath)).to.equal(typeof expected === 'string' ? path.join(dir, expected) : expected);
+  };
+
+  it('Testing exact multi-match', () => {
+    executeTest(['file', 'file.json'], 'file', 'file');
+  });
+
+  it('Testing partial match', () => {
+    executeTest(['file.json'], 'file', 'file.json');
+  });
+
+  it('Testing partial non-match', () => {
+    const files = ['file.json'];
+    executeTest(files, 'fil', null);
+    executeTest(files, 'file.', null);
+    executeTest(files, 'file.j', null);
+  });
+
+  it('Testing partial multi non-match', () => {
+    executeTest(['file.json', 'file.yml'], 'file', null);
+  });
+});