diff --git a/package-lock.json b/package-lock.json
index ee9b68df..4bd9880f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -55,7 +55,7 @@
         "yeoman-test": "^8.1.0"
       },
       "engines": {
-        "node": "^16.13.0 || >=18.12.0"
+        "node": "^18.17.0 || >=20.5.0"
       },
       "peerDependencies": {
         "@yeoman/types": "^1.1.1",
diff --git a/test/deprecate.test.ts b/test/deprecate.test.ts
index 2a6b4faf..1bfbfcdb 100644
--- a/test/deprecate.test.ts
+++ b/test/deprecate.test.ts
@@ -1,57 +1,229 @@
 /* eslint-disable import/no-named-as-default-member */
 import assert from 'node:assert';
 import chalk from 'chalk';
-import sinon from 'sinon';
+import sinon, { type SinonSpy } from 'sinon';
 import deprecate from '../src/util/deprecate.js';
 
+type SimpleObject = {
+  foo: number;
+  functionInObj: (someValue: number) => number;
+};
+
 describe('deprecate()', () => {
+  let fakeConsoleLog: SinonSpy;
   beforeEach(() => {
-    sinon.spy(console, 'log');
+    fakeConsoleLog = sinon.fake();
+    sinon.replace(console, 'log', fakeConsoleLog);
   });
 
   afterEach(() => {
-    console.log.restore();
+    sinon.restore();
   });
 
-  it('log a message', () => {
-    const func = sinon.spy();
-    const wrapped = deprecate('foo', func);
-    sinon.assert.notCalled(console.log);
-    wrapped('bar', 2);
-    sinon.assert.calledWith(console.log, chalk.yellow('(!) ') + 'foo');
-    sinon.assert.calledWith(func, 'bar', 2);
+  describe('deprecate a function', () => {
+    let deprecatedLogSpy: SinonSpy;
+    beforeEach(() => {
+      deprecatedLogSpy = sinon.fake();
+      sinon.replace(deprecate, 'log', deprecatedLogSpy);
+    });
+
+    afterEach(() => {
+      sinon.restore();
+    });
+
+    it('the original function is still called', () => {
+      const originalFunction = sinon.spy();
+      const deprecatedFunction = deprecate('this is function deprecated', originalFunction);
+
+      deprecatedFunction('baz', 3);
+      assert.ok(
+        originalFunction.calledWith('baz', 3),
+        `original function called with (${originalFunction.lastCall.args[0]}, ${originalFunction.lastCall.args[1]})`,
+      );
+    });
+
+    it('a call to deprecate.log(msg) is added', () => {
+      const originalFunction = sinon.spy();
+      const deprecatedFunction = deprecate('this is function deprecated', originalFunction);
+
+      originalFunction('bar', 2);
+      assert.ok(originalFunction.calledWith('bar', 2), 'original function not called with ("bar", 2)');
+      assert.ok(deprecatedLogSpy.notCalled);
+
+      deprecatedFunction('baz', 3);
+      assert.ok(deprecatedLogSpy.calledWith('this is function deprecated'));
+    });
+  });
+
+  describe('.log', () => {
+    it('logs the message in yellow, starting with "(!) "', () => {
+      deprecate.log('this is the message');
+      assert.ok(fakeConsoleLog.calledWith(chalk.yellow('(!) ') + 'this is the message'));
+    });
   });
 
   describe('.object()', () => {
-    it('wrap an object and log a message', () => {
-      const dummy = {
+    let deprecatedLogSpy: SinonSpy;
+    beforeEach(() => {
+      deprecatedLogSpy = sinon.fake();
+      sinon.replace(deprecate, 'log', deprecatedLogSpy);
+    });
+
+    afterEach(() => {
+      sinon.restore();
+    });
+
+    it('deprecates all functions/methods in the object', () => {
+      type SomeOtherObject = SimpleObject & {
+        anotherFunction: (someValue: string) => string;
+      };
+      const originalObject: SomeOtherObject = {
         foo: 1,
-        func: sinon.spy(),
+        functionInObj(someValue: number): number {
+          return someValue - 1;
+        },
+        anotherFunction(someValue: string): string {
+          return `${someValue} and ${someValue}`;
+        },
       };
-      const wrapped = deprecate.object('<%= name %> is deprecated', dummy);
 
-      // Keep values
-      assert.equal(wrapped.foo, 1);
+      // TODO When deprecate.js is changed to .ts, DeprecatedObject will be defined in deprecate.ts as something like type DeprecatedObject<O> = O;
+      const deprecatedObject = deprecate.object('<%= name %> is deprecated', originalObject);
+      // @ts-expect-error  The method functionInObj() does exist on deprecatedObject. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      deprecatedObject.functionInObj(42);
+      assert.ok(
+        deprecatedLogSpy.calledWith('functionInObj is deprecated'),
+        `last call with args: ${deprecatedLogSpy.lastCall.args[0]}`,
+      );
 
-      // Wrap methods
-      wrapped.func(2);
-      sinon.assert.calledWith(dummy.func, 2);
-      sinon.assert.calledWith(console.log, chalk.yellow('(!) ') + 'func is deprecated');
+      // @ts-expect-error  The method anotherFunction() does exist on deprecatedObject. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      deprecatedObject.anotherFunction('something');
+      assert.ok(
+        deprecatedLogSpy.calledWith('anotherFunction is deprecated'),
+        `last call with args: ${deprecatedLogSpy.lastCall.args[0]}`,
+      );
+    });
+
+    it('properties that are not functions are not changed', () => {
+      const originalObject: SimpleObject = {
+        foo: 1,
+        functionInObj(someValue: number): number {
+          return someValue - 1;
+        },
+      };
+
+      const deprecatedObject = deprecate.object('The function "<%= name %>" is deprecated', originalObject);
+      // @ts-expect-error  The property foo does exist on deprecatedObject. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      const fooValue = deprecatedObject.foo;
+      assert.equal(fooValue, 1);
+      assert.ok(deprecatedLogSpy.notCalled);
+    });
+
+    it('property getters and setters are not changed', () => {
+      type ObjectWithGettersSetters = SimpleObject & {
+        get bar(): number;
+        set bar(someValue: number);
+      };
+
+      const originalObject: ObjectWithGettersSetters = {
+        foo: 10,
+        functionInObj(someValue: number): number {
+          return someValue - 1;
+        },
+        get bar(): number {
+          return this.foo * 2;
+        },
+        set bar(someValue: number) {
+          this.foo = someValue / 2;
+        },
+      };
+
+      const deprecatedObject = deprecate.object('The function "<%= name %>" is deprecated', originalObject);
+      // @ts-expect-error The getter bar does exist on the object. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      deprecatedObject.bar;
+      // @ts-expect-error The setter bar does exist on the object. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      deprecatedObject.bar = 7;
+
+      assert.ok(deprecatedLogSpy.notCalled);
+    });
+
+    it('deprecation message can be a template', () => {
+      const originalObject: SimpleObject = {
+        foo: 1,
+        functionInObj(someValue: number): number {
+          return someValue - 1;
+        },
+      };
+
+      const deprecatedObject = deprecate.object('The function "<%= name %>" is deprecated', originalObject);
+
+      // @ts-expect-error The method functionInObj() does exist on deprecatedObject. This should be a DeprecatedObject<SimpleObject>. When deprecate.js is changed to .ts, this can be implemented and no error will occur here.
+      deprecatedObject.functionInObj(42);
+
+      assert.ok(
+        deprecatedLogSpy.calledWith('The function "functionInObj" is deprecated'),
+        `last call with args: ${deprecatedLogSpy.lastCall.args[0]}`,
+      );
     });
   });
 
   describe('.property()', () => {
-    it('wrap a property getter and log a message', () => {
-      const dummy = {
+    let deprecatedLogSpy: SinonSpy;
+    beforeEach(() => {
+      deprecatedLogSpy = sinon.fake();
+      sinon.replace(deprecate, 'log', deprecatedLogSpy);
+    });
+
+    afterEach(() => {
+      sinon.restore();
+    });
+
+    it('the deprecated message shows when a property is accessed', () => {
+      const originalObject = {
         foo: 1,
       };
-      deprecate.property('foo is deprecated', dummy, 'foo');
+      deprecate.property('foo property is deprecated', originalObject, 'foo');
+
+      // Value is not affected; it remains the same
+      assert.equal(originalObject.foo, 1);
+
+      assert.ok(
+        deprecatedLogSpy.calledWith('foo property is deprecated'),
+        `deprecatedLogSpy called with (${deprecatedLogSpy.lastCall.args[0]})`,
+      );
+    });
+
+    it('property getters and setters are deprecated', () => {
+      type ObjectWithGettersSetters = SimpleObject & {
+        get bar(): number;
+        set bar(someValue: number);
+      };
+
+      const originalObject: ObjectWithGettersSetters = {
+        foo: 10,
+        functionInObj(someValue: number): number {
+          return someValue - 1;
+        },
+        get bar(): number {
+          return this.foo * 2;
+        },
+        set bar(someValue: number) {
+          this.foo = someValue / 2;
+        },
+      };
 
-      // Keep values
-      assert.equal(dummy.foo, 1);
+      deprecate.property('bar is deprecated', originalObject, 'bar');
+      originalObject.bar;
+      assert.ok(
+        deprecatedLogSpy.calledWith('bar is deprecated'),
+        `deprecatedLogSpy called with (${deprecatedLogSpy.lastCall.args[0]})`,
+      );
 
-      // Wrap methods
-      sinon.assert.calledWith(console.log, chalk.yellow('(!) ') + 'foo is deprecated');
+      originalObject.bar = 7;
+      assert.ok(
+        deprecatedLogSpy.calledWith('bar is deprecated'),
+        `deprecatedLogSpy called with (${deprecatedLogSpy.lastCall.args[0]})`,
+      );
     });
   });
 });