feat(MongoBinaryDownloadUrl): add archive generation for gentoo

re #639

Author: hasezoey

docs/guides/supported-systems.md

@@ -126,6 +126,15 @@ There are no official mongodb builds for Arch Distributions, but the `ubuntu` bi
 Because Arch* dosnt base on ubuntu, there is no specific ubuntu version associated with an arch version, so it defaults to highest supported `ubuntu` version
 :::
 
+### Gentoo
+
+<span class="badge badge--warning">Untested</span> <span class="badge badge--danger">Unsupported</span>
+
+There are no official mongodb builds for Gentoo Distributions, but the `debian` binaries work on most Gentoo systems, so they are used<br/>
+:::note
+Because Gentoo dosnt base on debian, there is no specific debian version associated with an gentoo version, so it defaults to highest supported `debian` version
+:::
+
 ### Alpine
 
 <span class="badge badge--danger">Unsupported</span>

packages/mongodb-memory-server-core/src/util/MongoBinaryDownloadUrl.ts

@@ -197,6 +197,17 @@ export class MongoBinaryDownloadUrl implements MongoBinaryDownloadUrlOpts {
         dist: 'Ubuntu Linux',
         release: '20.04',
       });
+    } else if (regexHelper(/gentoo/i, os)) {
+      // it seems like debian binaries work for gentoo too (at least most), see https://github.com/nodkz/mongodb-memory-server/issues/639
+      console.warn(
+        `There is no official build of MongoDB for Gentoo (${os.dist}). Falling back to Debian.`
+      );
+
+      return this.getDebianVersionString({
+        os: 'linux',
+        dist: 'Debian',
+        release: '11',
+      });
     } else if (regexHelper(/unknown/i, os)) {
       // "unknown" is likely to happen if no release file / command could be found
       console.warn(

packages/mongodb-memory-server-core/src/util/__tests__/MongoBinaryDownloadUrl.test.ts

@@ -291,7 +291,7 @@ describe('MongoBinaryDownloadUrl', () => {
           version: '3.6.3',
           os: {
             os: 'linux',
-            dist: 'Gentoo Linux',
+            dist: 'Something Unhandled', // not "unknown", because that is when it failed to parse
             release: '',
           },
         });
@@ -342,6 +342,46 @@ describe('MongoBinaryDownloadUrl', () => {
         expect(console.warn).toHaveBeenCalledTimes(1);
       });
 
+      describe('for gentoo', () => {
+        it('for gentoo 5.0.8', async () => {
+          jest.spyOn(console, 'warn').mockImplementation(() => void 0);
+
+          const du = new MongoBinaryDownloadUrl({
+            platform: 'linux',
+            arch: 'x64',
+            version: '5.0.8',
+            os: {
+              os: 'linux',
+              dist: 'gentoo',
+              release: '',
+            },
+          });
+          expect(await du.getDownloadUrl()).toBe(
+            'https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian11-5.0.8.tgz'
+          );
+          expect(console.warn).toHaveBeenCalledTimes(1);
+        });
+
+        it('for gentoo 4.4', async () => {
+          jest.spyOn(console, 'warn').mockImplementation(() => void 0);
+
+          const du = new MongoBinaryDownloadUrl({
+            platform: 'linux',
+            arch: 'x64',
+            version: '4.4.0',
+            os: {
+              os: 'linux',
+              dist: 'gentoo',
+              release: '',
+            },
+          });
+          expect(await du.getDownloadUrl()).toBe(
+            'https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian10-4.4.0.tgz'
+          );
+          expect(console.warn).toHaveBeenCalledTimes(1);
+        });
+      });
+
       it('for unpopular arch', async () => {
         jest.spyOn(console, 'warn').mockImplementation(() => void 0);