fix: Clarify error message when non-magical part of input glob does not exist

Author: stephan-noel

core/garment/__tests__/garment.test.ts

@@ -63,4 +63,21 @@ describe('createFileInput', () => {
 
     expect(filesCount).toBe(2);
   });
+
+  test('should throw with a clear error message when rootDir does not exist', async () => {
+    const testDir = await initFixture('basic');
+
+    const nonExistingDirectory = Path.join(testDir, 'nonExistingDirectory');
+    const generator = createFileInput({
+      rootDir: nonExistingDirectory
+    });
+
+    const createFileInputForNonExistingRootDirectory = () => {
+      generator.next();
+    };
+
+    expect(createFileInputForNonExistingRootDirectory).toThrow(
+      /nonExistingDirectory/
+    );
+  });
 });

core/garment/src/garment.ts

@@ -1083,6 +1083,11 @@ export function* createFileInput(
   { rootDir, files = [], include, exclude = [] }: Input,
   fsInstance = fs
 ) {
+  if (!fsInstance.existsSync(rootDir)) {
+    throw new Error(`The path ${rootDir} does not exist, please check the input property
+     of your tasks in your garment.json file and verify that the "non-magical" part of your glob
+     is a path to an already existing directory`);
+  }
   const filesFromGlob = include
     ? globby.sync(include, {
         cwd: rootDir,