refactor: separate elements logic into a standalone package (#9285)

packages/element/tests/sizeHelpers.test.ts

@@ -0,0 +1,69 @@
+import { vi } from "vitest";
+
+import * as constants from "@excalidraw/common";
+
+import { getPerfectElementSize } from "../src/sizeHelpers";
+
+const EPSILON_DIGITS = 3;
+// Needed so that we can mock the value of constants which is done in
+// below tests. In Jest this wasn't needed as global override was possible
+// but vite doesn't allow that hence we need to mock
+vi.mock(
+  "@excalidraw/common",
+  //@ts-ignore
+  async (importOriginal) => {
+    const module: any = await importOriginal();
+    return { ...module };
+  },
+);
+describe("getPerfectElementSize", () => {
+  it("should return height:0 if `elementType` is line and locked angle is 0", () => {
+    const { height, width } = getPerfectElementSize("line", 149, 10);
+    expect(width).toBeCloseTo(149, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(0, EPSILON_DIGITS);
+  });
+
+  it("should return width:0 if `elementType` is line and locked angle is 90 deg (Math.PI/2)", () => {
+    const { height, width } = getPerfectElementSize("line", 10, 140);
+    expect(width).toBeCloseTo(0, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(140, EPSILON_DIGITS);
+  });
+
+  it("should return height:0 if `elementType` is arrow and locked angle is 0", () => {
+    const { height, width } = getPerfectElementSize("arrow", 200, 20);
+    expect(width).toBeCloseTo(200, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(0, EPSILON_DIGITS);
+  });
+  it("should return width:0 if `elementType` is arrow and locked angle is 90 deg (Math.PI/2)", () => {
+    const { height, width } = getPerfectElementSize("arrow", 10, 100);
+    expect(width).toBeCloseTo(0, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(100, EPSILON_DIGITS);
+  });
+
+  it("should return adjust height to be width * tan(locked angle)", () => {
+    const { height, width } = getPerfectElementSize("arrow", 120, 185);
+    expect(width).toBeCloseTo(120, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(207.846, EPSILON_DIGITS);
+  });
+
+  it("should return height equals to width if locked angle is 45 deg", () => {
+    const { height, width } = getPerfectElementSize("arrow", 135, 145);
+    expect(width).toBeCloseTo(135, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(135, EPSILON_DIGITS);
+  });
+
+  it("should return height:0 and width:0 when width and height are 0", () => {
+    const { height, width } = getPerfectElementSize("arrow", 0, 0);
+    expect(width).toBeCloseTo(0, EPSILON_DIGITS);
+    expect(height).toBeCloseTo(0, EPSILON_DIGITS);
+  });
+
+  describe("should respond to SHIFT_LOCKING_ANGLE constant", () => {
+    it("should have only 2 locking angles per section if SHIFT_LOCKING_ANGLE = 45 deg (Math.PI/4)", () => {
+      (constants as any).SHIFT_LOCKING_ANGLE = Math.PI / 4;
+      const { height, width } = getPerfectElementSize("arrow", 120, 185);
+      expect(width).toBeCloseTo(120, EPSILON_DIGITS);
+      expect(height).toBeCloseTo(120, EPSILON_DIGITS);
+    });
+  });
+});