fix: don't return empty ElectronVersions on fetch failures (#117)

Author: dsanders11

src/versions.ts

@@ -292,6 +292,11 @@ export class ElectronVersions extends BaseVersions {
     const url = 'https://releases.electronjs.org/releases.json';
     d('fetching releases list from', url);
     const response = await fetch(url);
+    if (!response.ok) {
+      throw new Error(
+        `Fetching versions failed with status code: ${response.status}`,
+      );
+    }
     const json = (await response.json()) as unknown;
     await fs.outputJson(cacheFile, json);
     return json;
@@ -329,6 +334,9 @@ export class ElectronVersions extends BaseVersions {
         versions = await ElectronVersions.fetchVersions(versionsCache);
       } catch (err) {
         d('error fetching versions', err);
+        if (!versions) {
+          throw err;
+        }
       }
     }
 

tests/versions.test.ts

@@ -310,12 +310,26 @@ describe('ElectronVersions', () => {
       expect(versions.length).toBe(2);
     });
 
-    it('has no versions with a missing cache and failed fetch', async () => {
+    it('throws an error with a missing cache and failed fetch', async () => {
       const scope = nockScope.get('/releases.json').replyWithError('Error');
       await fs.remove(versionsCache);
-      const { versions } = await ElectronVersions.create({ versionsCache });
+      await expect(ElectronVersions.create({ versionsCache })).rejects.toThrow(
+        Error,
+      );
+      expect(scope.isDone());
+    });
+
+    it('throws an error with a missing cache and a non-200 server response', async () => {
+      const scope = nockScope
+        .get('/releases.json')
+        .reply(500, JSON.stringify({ error: true }), {
+          'Content-Type': 'application/json',
+        });
+      await fs.remove(versionsCache);
+      await expect(ElectronVersions.create({ versionsCache })).rejects.toThrow(
+        Error,
+      );
       expect(scope.isDone());
-      expect(versions.length).toBe(0);
     });
 
     it('fetches with a stale cache', async () => {