Fix: [#20] Check external package import path

Author: doteric

src/utils/getImportedPackages.test.ts

@@ -238,4 +238,43 @@ describe('getImportedPackages', () => {
       archiver: '3.2.1',
     });
   });
+
+  it('skips relative specifiers marked as external', () => {
+    const metafileMock: Metafile = {
+      inputs: {
+        '../../../common/slack/parseMiddleware.js': {
+          bytes: 1000,
+          imports: [],
+        },
+        'example/example.ts': {
+          bytes: 130,
+          imports: [
+            {
+              path: '../../../common/slack/parseMiddleware.js',
+              kind: 'import-statement',
+              external: true,
+            },
+            {
+              path: 'archiver',
+              kind: 'import-statement',
+              external: true,
+            },
+          ],
+        },
+      },
+      outputs: {
+        'example/dist/testfunc.js': {
+          imports: [],
+          exports: [],
+          entryPoint: 'example/example.ts',
+          inputs: {},
+          bytes: 82693,
+        },
+      },
+    };
+    const packages = getImportedPackages('example/example.ts', metafileMock);
+    expect(packages).toEqual({
+      archiver: '3.2.1',
+    });
+  });
 });

src/utils/getImportedPackages.ts

@@ -65,7 +65,16 @@ const getImportedPackages = (
       }
     */
     // TODO: Extract to separate file and add full tests for various scenarios
-    if (inputImport.external === true) {
+
+    // Node Package decision based on https://nodejs.org/api/esm.html#terminology
+    // Check if it's a relative specifier (./ or ../) or absolute specifier (/ or file://)
+    const isRelativeOrAbsoluteSpecifier =
+      inputImport.path.startsWith('./') ||
+      inputImport.path.startsWith('../') ||
+      inputImport.path.startsWith('/') ||
+      inputImport.path.startsWith('file://');
+
+    if (inputImport.external === true && !isRelativeOrAbsoluteSpecifier) {
       const packageName = inputImport.path.startsWith('@')
         ? inputImport.path.split('/').slice(0, 2).join('/')
         : inputImport.path.split('/')[0];