diff --git a/test/classes/mapping/post.ts b/test/classes/mapping/post.ts
new file mode 100644
index 0000000..7b2e103
--- /dev/null
+++ b/test/classes/mapping/post.ts
@@ -0,0 +1,33 @@
+"use strict";
+
+// Public module from npm
+import chai from "chai";
+import chaiAsPromised from "chai-as-promised";
+import { INVALID_POST_ID, USER_NOT_LOGGED } from "../../../src/scripts/classes/errors";
+
+// Module from files
+import { Post } from "../../../src";
+import Shared from "../../../src/scripts/shared";
+
+chai.use(chaiAsPromised);
+const { expect } = chai;
+
+export function suite(): void {
+  it("Fetch post with null ID", async function fetchWithNullID() {
+    Shared.setIsLogged(true);
+    const post = new Post(null);
+    await expect(post.fetch()).to.be.rejectedWith(INVALID_POST_ID);
+  });
+
+  it("Fetch post with invalid ID", async function fetchWithInvalidID() {
+    Shared.setIsLogged(true);
+    const post = new Post(-1);
+    await expect(post.fetch()).to.be.rejectedWith(INVALID_POST_ID);
+  });
+
+  it("Fetch post without authentication", async function fetchWithoutAuth() {
+    Shared.setIsLogged(false);
+    const post = new Post(1234);
+    await expect(post.fetch()).to.be.rejectedWith(USER_NOT_LOGGED);
+  });
+}
diff --git a/test/classes/mapping/thread.ts b/test/classes/mapping/thread.ts
new file mode 100644
index 0000000..e9bac61
--- /dev/null
+++ b/test/classes/mapping/thread.ts
@@ -0,0 +1,41 @@
+"use strict";
+
+// Public module from npm
+import chai from "chai";
+import chaiAsPromised from "chai-as-promised";
+import { INVALID_THREAD_ID, USER_NOT_LOGGED } from "../../../src/scripts/classes/errors";
+
+// Module from files
+import { Thread } from "../../../src";
+import Shared from "../../../src/scripts/shared";
+
+chai.use(chaiAsPromised);
+const { expect } = chai;
+
+export function suite(): void {
+  it("Fetch thread with invalid ID", async function fetchWithInvalidID() {
+    Shared.setIsLogged(true);
+    const thread = new Thread(-1);
+    await expect(thread.fetch()).to.be.rejectedWith(INVALID_THREAD_ID);
+  });
+
+  it("Fetch thread with null ID", async function fetchWithNullID() {
+    Shared.setIsLogged(true);
+    const thread = new Thread(null);
+    await expect(thread.fetch()).to.be.rejectedWith(INVALID_THREAD_ID);
+  });
+
+  it("Fetch thread without authentication", async function fetchWithoutAuth() {
+    Shared.setIsLogged(false);
+    const thread = new Thread(1234);
+    await expect(thread.fetch()).to.be.rejectedWith(USER_NOT_LOGGED);
+  });
+
+  it("Fetch post with invalid ID", async function fetchWithInvalidID() {
+    Shared.setIsLogged(true);
+    const thread = new Thread(-1);
+    await expect(thread.getPost(0)).to.be.rejectedWith(
+      "Index must be greater or equal than 1"
+    );
+  });
+}
diff --git a/test/classes/mapping/user-profile.ts b/test/classes/mapping/user-profile.ts
new file mode 100644
index 0000000..1644ba8
--- /dev/null
+++ b/test/classes/mapping/user-profile.ts
@@ -0,0 +1,21 @@
+"use strict";
+
+// Public module from npm
+import chai from "chai";
+import chaiAsPromised from "chai-as-promised";
+import { INVALID_USER_ID, USER_NOT_LOGGED } from "../../../src/scripts/classes/errors";
+
+// Module from files
+import { UserProfile } from "../../../src";
+import Shared from "../../../src/scripts/shared";
+
+chai.use(chaiAsPromised);
+const { expect } = chai;
+
+export function suite(): void {
+  it("Fetch profile without authentication", async function fetchWithoutAuth() {
+    Shared.setIsLogged(false);
+    const up = new UserProfile();
+    await expect(up.fetch()).to.be.rejectedWith(USER_NOT_LOGGED);
+  });
+}