refactor(prompts): consolidate file path checks (#600)

* refactor(prompts): consolidate file path checks

* docs: JSDoc clarification

* test: add a few test cases

* test: small flaky test fix

__tests__/index.test.ts

@@ -114,7 +114,7 @@ describe('cli', () => {
     conf.set('apiKey', '123456');
 
     await expect(cli(['docs'])).rejects.toThrow('No folder provided. Usage `rdme docs <folder> [options]`.');
-    conf.delete('apiKey');
+    conf.clear();
   });
 
   it('should error with `rdme oas` arguments passed in', async () => {

__tests__/lib/checkFile.test.ts

@@ -0,0 +1,33 @@
+import fs from 'fs';
+
+import { checkFilePath } from '../../src/lib/checkFile';
+
+describe('#checkFilePath', () => {
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it('should return error for empty path value', () => {
+    return expect(checkFilePath('')).toBe('An output path must be supplied.');
+  });
+
+  it('should return error if path already exists', () => {
+    expect.assertions(2);
+    const testPath = 'path-that-already-exists';
+
+    fs.existsSync = jest.fn(() => true);
+
+    expect(checkFilePath(testPath)).toBe('Specified output path already exists.');
+    expect(fs.existsSync).toHaveBeenCalledWith(testPath);
+  });
+
+  it("should return true if the path doesn't exist", () => {
+    expect.assertions(2);
+    const testPath = 'path-that-does-not-exist';
+
+    fs.existsSync = jest.fn(() => false);
+
+    expect(checkFilePath(testPath)).toBe(true);
+    expect(fs.existsSync).toHaveBeenCalledWith(testPath);
+  });
+});

src/cmds/openapi/reduce.ts

@@ -9,6 +9,7 @@ import oasReducer from 'oas/dist/lib/reducer';
 import ora from 'ora';
 
 import Command, { CommandCategories } from '../../lib/baseCommand';
+import { checkFilePath } from '../../lib/checkFile';
 import { oraOptions } from '../../lib/logger';
 import prepareOas from '../../lib/prepareOas';
 import promptTerminal from '../../lib/promptWrapper';
@@ -131,17 +132,7 @@ export default class OpenAPIReduceCommand extends Command {
           const extension = path.extname(specPath);
           return `${path.basename(specPath).split(extension)[0]}-reduced${extension}`;
         },
-        validate: value => {
-          if (value.length) {
-            if (!fs.existsSync(value)) {
-              return true;
-            }
-
-            return 'Specified output path already exists.';
-          }
-
-          return 'An output path must be supplied.';
-        },
+        validate: value => checkFilePath(value),
       },
     ]);
 

src/lib/checkFile.ts

@@ -0,0 +1,30 @@
+import fs from 'fs';
+
+/**
+ * Removes any non-alphanumeric characters and replaces them with hyphens.
+ *
+ * This is used for file names and for YAML keys.
+ */
+export const cleanFileName = (input: string) => input.replace(/[^a-z0-9]/gi, '-');
+
+/**
+ * A validator function used in our prompts for when a user
+ * is prompted to specify a file path.
+ *
+ * @param value the file name
+ * @param getFullPath An optional function for adding a file path or any filename validations
+ * @returns true if path is valid (i.e. is non-empty and doesn't already exist),
+ * otherwise a string containing the error message
+ */
+export function checkFilePath(value: string, getFullPath: (file: string) => string = file => file) {
+  if (value.length) {
+    const fullPath = getFullPath(value);
+    if (!fs.existsSync(fullPath)) {
+      return true;
+    }
+
+    return 'Specified output path already exists.';
+  }
+
+  return 'An output path must be supplied.';
+}

src/lib/createGHA/index.ts

@@ -12,6 +12,7 @@ import simpleGit from 'simple-git';
 
 import { transcludeString } from 'hercule/promises';
 
+import { checkFilePath, cleanFileName } from '../checkFile';
 import configstore from '../configstore';
 import { getPkgVersion } from '../getPkgVersion';
 import isCI from '../isCI';
@@ -44,13 +45,6 @@ export const getMajorRdmeVersion = async () => semverMajor(await getPkgVersion()
 
 export const git = simpleGit();
 
-/**
- * Removes any non-alphanumeric characters and replaces them with hyphens.
- *
- * This is used for file names and for YAML keys.
- */
-const cleanFileName = (input: string) => input.replace(/[^a-z0-9]/gi, '-');
-
 /**
  * Removes any non-file-friendly characters and adds
  * the full path + file extension for GitHub Workflow files.
@@ -255,18 +249,7 @@ export default async function createGHA(
           type: 'text',
           initial: cleanFileName(`rdme-${command}`),
           format: prev => getGHAFileName(prev),
-          validate: value => {
-            if (value.length) {
-              const fullPath = getGHAFileName(value);
-              if (!fs.existsSync(fullPath)) {
-                return true;
-              }
-
-              return 'Specified output path already exists.';
-            }
-
-            return 'An output path must be supplied.';
-          },
+          validate: value => checkFilePath(value, getGHAFileName),
         },
       ],
       {