Add tests, remove carriage returns.

frontend/toast/__tests__/toast_internal_support_test.ts

@@ -1,5 +1,39 @@
+const mockRun = jest.fn();
+
+class MockFBToast {
+  static everyMessage: Record<string, boolean> = {};
+  run = mockRun;
+}
+
+jest.mock("../fb_toast", () => {
+  return { FBToast: MockFBToast };
+});
+
+import { FBToast } from "../fb_toast";
+import { createToastOnce, createToast } from "../toast_internal_support";
+
 describe("toast internal support files", () => {
   it("creates a toast and attaches to DOM", () => {
+    const msg = "foo";
+    const fallback = jest.fn();
+    const container = document.createElement("DIV");
+    container.className = "toast-container";
+    document.body.appendChild(container);
 
+    createToastOnce(msg, "bar", "baz", fallback);
+
+    expect(FBToast.everyMessage[msg]).toBe(true);
+    expect(fallback).not.toHaveBeenCalled();
+    expect(mockRun).toHaveBeenCalled();
+
+    createToastOnce(msg, "bar", "baz", fallback);
+
+    expect(fallback).toHaveBeenCalled();
+  });
+
+  it("crashes if you don't attach .toast-container", () => {
+    document.body.innerHTML = "";
+    expect(() => createToast("x", "y", "z"))
+      .toThrow();
   });
 });

frontend/toast/fb_toast.ts

@@ -23,15 +23,17 @@ export class FBToast {
 
   /** Declare if the user's mouse is hovering over the message. */
   public isHovered = false;
+  public message = "";
 
   constructor(public parent: Element,
     title: string,
-    public message: string,
+    raw_message: string,
     color: string) {
 
+    this.message = raw_message.replace(/\s+/g, " ");
     /** Fill contents. */
     this.titleEl.innerText = title;
-    this.messageEl.innerText = message;
+    this.messageEl.innerText = this.message;
 
     /** Add classes. */
     this.toastEl.classList.add("toast");
@@ -105,7 +107,6 @@ export class FBToast {
   };
 
   run = () => {
-
     /** Append children. */
     this.parent.appendChild(this.toastEl);
     // TSC Thinks this is a node project :-\