diff --git a/spec/operators/defaultIfEmpty-spec.ts b/spec/operators/defaultIfEmpty-spec.ts
index 28737b376b..db501ac07b 100644
--- a/spec/operators/defaultIfEmpty-spec.ts
+++ b/spec/operators/defaultIfEmpty-spec.ts
@@ -1,94 +1,119 @@
+/** @prettier */
 import { expect } from 'chai';
-import { hot, cold, expectObservable, expectSubscriptions } from '../helpers/marble-testing';
+import { observableMatcher } from '../helpers/observableMatcher';
 import { of, Observable } from 'rxjs';
 import { defaultIfEmpty, mergeMap, take } from 'rxjs/operators';
+import { TestScheduler } from 'rxjs/testing';
 
 /** @test {defaultIfEmpty} */
-describe('Observable.prototype.defaultIfEmpty', () => {
+describe('defaultIfEmpty', () => {
+  let testScheduler: TestScheduler;
+
+  beforeEach(() => {
+    testScheduler = new TestScheduler(observableMatcher);
+  });
+
   it('should return the Observable if not empty with a default value', () => {
-    const e1 =   hot('--------|');
-    const expected = '--------(x|)';
+    testScheduler.run(({ hot, expectObservable, expectSubscriptions }) => {
+      const e1 = hot('  --------|');
+      const e1subs = '  ^-------!';
+      const expected = '--------(x|)';
 
-    // TODO: Fix `defaultIfEmpty` typings
-    expectObservable(e1.pipe(defaultIfEmpty(42) as any)).toBe(expected, { x: 42 });
+      expectObservable(e1.pipe(defaultIfEmpty(42))).toBe(expected, { x: 42 });
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should return the argument if Observable is empty', () => {
-    const e1 =  cold('|');
-    const e1subs =   '(^!)';
-    const expected = '(x|)';
+    testScheduler.run(({ cold, expectObservable, expectSubscriptions }) => {
+      const e1 = cold(' |');
+      const e1subs = '  (^!)';
+      const expected = '(x|)';
 
-    expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should return null if the Observable is empty and no arguments', () => {
-    const e1 =  cold('|');
-    const e1subs =   '(^!)';
-    const expected = '(x|)';
+    testScheduler.run(({ cold, expectObservable, expectSubscriptions }) => {
+      const e1 = cold(' |');
+      const e1subs = '  (^!)';
+      const expected = '(x|)';
 
-    expectObservable(e1.pipe(defaultIfEmpty())).toBe(expected, { x: null });
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(e1.pipe(defaultIfEmpty())).toBe(expected, { x: null });
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should return the Observable if not empty with a default value', () => {
-    const e1 =   hot('--a--b--|');
-    const e1subs =   '^       !';
-    const expected = '--a--b--|';
+    testScheduler.run(({ hot, expectObservable, expectSubscriptions }) => {
+      const e1 = hot('  --a--b--|');
+      const e1subs = '  ^-------!';
+      const expected = '--a--b--|';
 
-    expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should return the Observable if not empty with no default value', () => {
-    const e1 =   hot('--a--b--|');
-    const e1subs =   '^       !';
-    const expected = '--a--b--|';
+    testScheduler.run(({ hot, expectObservable, expectSubscriptions }) => {
+      const e1 = hot('  --a--b--|');
+      const e1subs = '  ^-------!';
+      const expected = '--a--b--|';
 
-    expectObservable(e1.pipe(defaultIfEmpty())).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(e1.pipe(defaultIfEmpty())).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should allow unsubscribing early and explicitly', () => {
-    const e1 =   hot('--a--b--|');
-    const e1subs =   '^   !    ';
-    const expected = '--a--    ';
-    const unsub =    '    !    ';
+    testScheduler.run(({ hot, expectObservable, expectSubscriptions }) => {
+      const e1 = hot('  --a--b--|');
+      const e1subs = '  ^---!    ';
+      const expected = '--a--    ';
+      const unsub = '   ----!    ';
 
-    const result = e1.pipe(defaultIfEmpty('x'));
+      const result = e1.pipe(defaultIfEmpty('x'));
 
-    expectObservable(result, unsub).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(result, unsub).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should not break unsubscription chains when unsubscribed explicitly', () => {
-    const e1 =   hot('--a--b--|');
-    const e1subs =   '^   !    ';
-    const expected = '--a--    ';
-    const unsub =    '    !    ';
-
-    const result = e1.pipe(
-      mergeMap(x => of(x)),
-      defaultIfEmpty('x'),
-      mergeMap(x => of(x)),
-    );
-
-    expectObservable(result, unsub).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    testScheduler.run(({ hot, expectObservable, expectSubscriptions }) => {
+      const e1 = hot('  --a--b--|');
+      const e1subs = '  ^---!    ';
+      const expected = '--a--    ';
+      const unsub = '   ----!    ';
+
+      const result = e1.pipe(
+        mergeMap((x) => of(x)),
+        defaultIfEmpty('x'),
+        mergeMap((x) => of(x))
+      );
+
+      expectObservable(result, unsub).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should error if the Observable errors', () => {
-    const e1 =  cold('#');
-    const e1subs =   '(^!)';
-    const expected = '#';
+    testScheduler.run(({ cold, expectObservable, expectSubscriptions }) => {
+      const e1 = cold(' #');
+      const e1subs = '  (^!)';
+      const expected = '#';
 
-    expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
-    expectSubscriptions(e1.subscriptions).toBe(e1subs);
+      expectObservable(e1.pipe(defaultIfEmpty('x'))).toBe(expected);
+      expectSubscriptions(e1.subscriptions).toBe(e1subs);
+    });
   });
 
   it('should stop listening to a synchronous observable when unsubscribed', () => {
     const sideEffects: number[] = [];
-    const synchronousObservable = new Observable(subscriber => {
+    const synchronousObservable = new Observable((subscriber) => {
       // This will check to see if the subscriber was closed on each loop
       // when the unsubscribe hits (from the `take`), it should be closed
       for (let i = 0; !subscriber.closed && i < 10; i++) {
@@ -97,10 +122,9 @@ describe('Observable.prototype.defaultIfEmpty', () => {
       }
     });
 
-    synchronousObservable.pipe(
-      defaultIfEmpty(0),
-      take(3),
-    ).subscribe(() => { /* noop */ });
+    synchronousObservable.pipe(defaultIfEmpty(0), take(3)).subscribe(() => {
+      /* noop */
+    });
 
     expect(sideEffects).to.deep.equal([0, 1, 2]);
   });