diff --git a/lib/datasource/__snapshots__/index.spec.ts.snap b/lib/datasource/__snapshots__/index.spec.ts.snap
index d554bca3cfef1bf9abf7f53659118eb03e583fd9..269e3ed3267ddebcc0565ed303e44a124baee401 100644
--- a/lib/datasource/__snapshots__/index.spec.ts.snap
+++ b/lib/datasource/__snapshots__/index.spec.ts.snap
@@ -22,20 +22,3 @@ Object {
   "sourceUrl": "https://github.com/nodejs/node",
 }
 `;
-
-exports[`datasource/index merges registries and returns success 1`] = `
-Object {
-  "releases": Array [
-    Object {
-      "registryUrl": "https://reg1.com",
-      "version": "1.0.0",
-    },
-    Object {
-      "registryUrl": "https://reg1.com",
-      "version": "1.1.0",
-    },
-  ],
-}
-`;
-
-exports[`datasource/index warns if multiple registryUrls for registryStrategy=first 1`] = `null`;
diff --git a/lib/datasource/index.spec.ts b/lib/datasource/index.spec.ts
index 1247412c69044456c6cf58eb6db734be33ad9096..af0a1c4b42039a2d7cca7d2b619ab3d23077e129 100644
--- a/lib/datasource/index.spec.ts
+++ b/lib/datasource/index.spec.ts
@@ -116,10 +116,10 @@ describe(getName(), () => {
       datasource: datasourceNpm.id,
       depName: 'react-native',
     });
-    // FIXME: explicit assert condition
-    expect(res).toMatchSnapshot();
-    expect(res.changelogUrl).toBeDefined();
-    expect(res.sourceUrl).toBeDefined();
+    expect(res).toMatchSnapshot({
+      changelogUrl:
+        'https://github.com/react-native-community/react-native-releases/blob/master/CHANGELOG.md',
+    });
   });
   it('applies extractVersion', async () => {
     npmDatasource.getReleases.mockResolvedValue({
@@ -146,9 +146,9 @@ describe(getName(), () => {
       datasource: datasourceNpm.id,
       depName: 'node',
     });
-    // FIXME: explicit assert condition
-    expect(res).toMatchSnapshot();
-    expect(res.sourceUrl).toBeDefined();
+    expect(res).toMatchSnapshot({
+      sourceUrl: 'https://github.com/nodejs/node',
+    });
   });
   it('ignores and warns for registryUrls', async () => {
     await datasource.getPkgReleases({
@@ -165,8 +165,7 @@ describe(getName(), () => {
       depName: 'something',
       registryUrls: ['https://docker.com', 'https://docker.io'],
     });
-    // FIXME: explicit assert condition
-    expect(res).toMatchSnapshot();
+    expect(res).toBeNull();
   });
   it('hunts registries and returns success', async () => {
     packagistDatasource.getReleases.mockResolvedValueOnce(null);
@@ -231,9 +230,18 @@ describe(getName(), () => {
       depName: 'something',
       registryUrls: ['https://reg1.com', 'https://reg2.io'],
     });
-    // FIXME: explicit assert condition
-    expect(res).toMatchSnapshot();
-    expect(res.releases).toHaveLength(2);
+    expect(res).toEqual({
+      releases: [
+        {
+          registryUrl: 'https://reg1.com',
+          version: '1.0.0',
+        },
+        {
+          registryUrl: 'https://reg1.com',
+          version: '1.1.0',
+        },
+      ],
+    });
   });
   it('merges registries and aborts on ExternalHostError', async () => {
     mavenDatasource.getReleases.mockImplementationOnce(() => {
diff --git a/lib/datasource/metadata.spec.ts b/lib/datasource/metadata.spec.ts
index e17b35feccea62223a94ff85c3d724190abf2ccd..eb27c5e7a7ebf4d75b7ba0d197dd23f79fa59999 100644
--- a/lib/datasource/metadata.spec.ts
+++ b/lib/datasource/metadata.spec.ts
@@ -3,6 +3,7 @@ import * as datasourceMaven from './maven';
 import { addMetaData } from './metadata';
 import * as datasourceNpm from './npm';
 import { PypiDatasource } from './pypi';
+import type { ReleaseResult } from './types';
 
 describe(getName(), () => {
   it('Should do nothing if dep is not specified', () => {
@@ -10,7 +11,7 @@ describe(getName(), () => {
   });
 
   it('Should handle manualChangelogUrls', () => {
-    const dep = {
+    const dep: ReleaseResult = {
       releases: [
         { version: '2.0.0', releaseTimestamp: '2018-07-13T10:14:17.000Z' },
         {
@@ -26,12 +27,14 @@ describe(getName(), () => {
     const lookupName = 'django';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      changelogUrl:
+        'https://github.com/django/django/tree/master/docs/releases',
+    });
   });
 
   it('Should handle manualSourceUrls', () => {
-    const dep = {
+    const dep: ReleaseResult = {
       releases: [
         { version: '2.0.0', releaseTimestamp: '2018-07-13T10:14:17.000Z' },
         {
@@ -47,12 +50,13 @@ describe(getName(), () => {
     const lookupName = 'mkdocs';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      sourceUrl: 'https://github.com/mkdocs/mkdocs',
+    });
   });
 
   it('Should handle parsing of sourceUrls correctly', () => {
-    const dep = {
+    const dep: ReleaseResult = {
       sourceUrl: 'https://github.com/carltongibson/django-filter/tree/master',
       releases: [
         { version: '2.0.0', releaseTimestamp: '2018-07-13T10:14:17.000Z' },
@@ -68,12 +72,13 @@ describe(getName(), () => {
     const lookupName = 'django-filter';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      sourceUrl: 'https://github.com/carltongibson/django-filter',
+    });
   });
 
   it('Should handle parsing of sourceUrls correctly for GitLab also', () => {
-    const dep = {
+    const dep: ReleaseResult = {
       sourceUrl: 'https://gitlab.com/meno/dropzone/tree/master',
       releases: [
         { version: '5.7.0', releaseTimestamp: '2020-02-14T13:12:00.000Z' },
@@ -87,8 +92,9 @@ describe(getName(), () => {
     const lookupName = 'dropzone';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      sourceUrl: 'https://gitlab.com/meno/dropzone',
+    });
   });
   it('Should handle failed parsing of sourceUrls for GitLab', () => {
     const dep = {
@@ -105,8 +111,9 @@ describe(getName(), () => {
     const lookupName = 'dropzone';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      sourceUrl: 'https://gitlab-nope',
+    });
   });
   it('Should handle failed parsing of sourceUrls for other', () => {
     const dep = {
@@ -123,8 +130,9 @@ describe(getName(), () => {
     const lookupName = 'dropzone';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
-    expect(dep).toMatchSnapshot();
+    expect(dep).toMatchSnapshot({
+      sourceUrl: 'https://nope-nope-nope',
+    });
   });
   it('Should handle non-url', () => {
     const dep = {
@@ -141,7 +149,7 @@ describe(getName(), () => {
     const lookupName = 'dropzone';
 
     addMetaData(dep, datasource, lookupName);
-    // FIXME: explicit assert condition
+    expect(dep).not.toContainKey('sourceUrl');
     expect(dep).toMatchSnapshot();
   });