diff --git a/lib/versioning/ruby/index.spec.ts b/lib/versioning/ruby/index.spec.ts
index 3e2c9af76f2fda82f01a94cad7ea39156dd3b021..40829c1026ebb5191da49c387974bd7f651fc347 100644
--- a/lib/versioning/ruby/index.spec.ts
+++ b/lib/versioning/ruby/index.spec.ts
@@ -174,12 +174,12 @@ describe('versioning/ruby/index', () => {
     ${'2.0.0'}       | ${'>= 1.1.5, < 2.0'}   | ${false}
     ${'1.2.0-beta'}  | ${'1.2.0-alpha'}       | ${false}
     ${'2.0.0'}       | ${'> 1.2.2, ~> 2.0.0'} | ${false}
-    ${'asdf'}        | ${'> 1.2.2, ~> 2.0.0'} | ${null}
-    ${null}          | ${'> 1.2.2, ~> 2.0.0'} | ${null}
+    ${'asdf'}        | ${'> 1.2.2, ~> 2.0.0'} | ${false}
+    ${null}          | ${'> 1.2.2, ~> 2.0.0'} | ${false}
   `(
     'isLessThanRange("$version", "$range") === "$expected"',
     ({ version, range, expected }) => {
-      expect(semverRuby.isLessThanRange(version, range)).toBe(expected);
+      expect(semverRuby.isLessThanRange?.(version, range)).toBe(expected);
     }
   );
 
diff --git a/lib/versioning/ruby/index.ts b/lib/versioning/ruby/index.ts
index e0566af075273e209b0076a375a3ae9449d3c834..b2218b687381fa73e66f0065bc903618b04c9faa 100644
--- a/lib/versioning/ruby/index.ts
+++ b/lib/versioning/ruby/index.ts
@@ -45,7 +45,7 @@ export const isVersion = (version: string): boolean => !!valid(vtrim(version));
 const isGreaterThan = (left: string, right: string): boolean =>
   gt(vtrim(left), vtrim(right));
 const isLessThanRange = (version: string, range: string): boolean =>
-  ltr(vtrim(version), vtrim(range));
+  !!ltr(vtrim(version), vtrim(range));
 
 const isSingleVersion = (range: string): boolean => {
   const { version, operator } = parseRange(vtrim(range));
@@ -74,17 +74,25 @@ export const isValid = (input: string): boolean =>
 
 export const matches = (version: string, range: string): boolean =>
   satisfies(vtrim(version), vtrim(range));
-const getSatisfyingVersion = (versions: string[], range: string): string =>
-  maxSatisfying(versions.map(vtrim), vtrim(range));
-const minSatisfyingVersion = (versions: string[], range: string): string =>
-  minSatisfying(versions.map(vtrim), vtrim(range));
+function getSatisfyingVersion(
+  versions: string[],
+  range: string
+): string | null {
+  return maxSatisfying(versions.map(vtrim), vtrim(range));
+}
+function minSatisfyingVersion(
+  versions: string[],
+  range: string
+): string | null {
+  return minSatisfying(versions.map(vtrim), vtrim(range));
+}
 
 const getNewValue = ({
   currentValue,
   rangeStrategy,
   currentVersion,
   newVersion,
-}: NewValueConfig): string => {
+}: NewValueConfig): string | null => {
   let newValue = null;
   if (isVersion(currentValue)) {
     newValue = currentValue.startsWith('v') ? 'v' + newVersion : newVersion;
@@ -123,7 +131,7 @@ const getNewValue = ({
         logger.warn(`Unsupported strategy ${rangeStrategy}`);
     }
   }
-  if (regEx(/^('|")/).exec(currentValue)) {
+  if (newValue && regEx(/^('|")/).exec(currentValue)) {
     const delimiter = currentValue[0];
     return newValue
       .split(',')
diff --git a/lib/versioning/ruby/range.ts b/lib/versioning/ruby/range.ts
index c6e8b0d72c0bd13c19b80122c6b3fe9c2ef31d6b..8230d1d7fed1c66680c2aeb71eb3460822636f2d 100644
--- a/lib/versioning/ruby/range.ts
+++ b/lib/versioning/ruby/range.ts
@@ -18,14 +18,14 @@ const parse = (range: string): Range => {
   const value = (range || '').trim();
 
   const match = regExp.exec(value);
-  if (match) {
-    const { version = null, operator = null, delimiter = ' ' } = match.groups;
+  if (match?.groups) {
+    const { version = '', operator = '', delimiter = ' ' } = match.groups;
     return { version, operator, delimiter };
   }
 
   return {
-    version: null,
-    operator: null,
+    version: '',
+    operator: '',
     delimiter: ' ',
   };
 };
diff --git a/lib/versioning/ruby/strategies/replace.ts b/lib/versioning/ruby/strategies/replace.ts
index 848fba0f37862d51bed6b489712b7488dcb72246..6b37aa27efdfc7981f02610dd17fd519408a7fbf 100644
--- a/lib/versioning/ruby/strategies/replace.ts
+++ b/lib/versioning/ruby/strategies/replace.ts
@@ -71,7 +71,8 @@ export default ({ to, range }: { range: string; to: string }): string => {
     const lastPart = range
       .split(',')
       .map((part) => part.trim())
-      .pop();
+      .slice(-1)
+      .join();
     const lastPartPrecision = lastPart.split('.').length;
     const toPrecision = to.split('.').length;
     let massagedTo: string = to;
diff --git a/lib/versioning/types.ts b/lib/versioning/types.ts
index 0e046086ff54f7ca350c5d758540ddd1ffadbc6c..cb2091c9f72444e40734ea105382529e00a3ce96 100644
--- a/lib/versioning/types.ts
+++ b/lib/versioning/types.ts
@@ -26,7 +26,7 @@ export interface VersioningApi {
   isLessThanRange?(version: string, range: string): boolean;
   getSatisfyingVersion(versions: string[], range: string): string | null;
   minSatisfyingVersion(versions: string[], range: string): string | null;
-  getNewValue(newValueConfig: NewValueConfig): string;
+  getNewValue(newValueConfig: NewValueConfig): string | null;
   sortVersions(version: string, other: string): number;
 
   matches(version: string, range: string | Range): boolean;
diff --git a/tsconfig.strict.json b/tsconfig.strict.json
index 1cda9093b7a1699a44015d0e73add6c3a42cbf5e..2008407999681b3dedc50d3e9b26efe1566f96fc 100644
--- a/tsconfig.strict.json
+++ b/tsconfig.strict.json
@@ -60,8 +60,7 @@
     "lib/util/split.ts",
     "lib/util/url.ts",
     "lib/versioning/maven/**/*.ts",
-    "lib/versioning/ruby/operator.ts",
-    "lib/versioning/ruby/version.ts",
+    "lib/versioning/ruby/**/*.ts",
     "lib/versioning/semver-coerced/**/*.ts",
     "lib/versioning/semver/**/*.ts",
     "lib/versioning/swift/**/*.ts",