Some cleanup

packages/mermaid-layout-elk/src/__tests__/geometry.spec.ts

@@ -0,0 +1,67 @@
+import { describe, it, expect } from 'vitest';
+import {
+  intersection,
+  ensureTrulyOutside,
+  makeInsidePoint,
+  tryNodeIntersect,
+  replaceEndpoint,
+  type RectLike,
+  type P,
+} from '../geometry.js';
+
+const approx = (a: number, b: number, eps = 1e-6) => Math.abs(a - b) < eps;
+
+describe('geometry helpers', () => {
+  it('intersection: vertical approach hits bottom border', () => {
+    const rect: RectLike = { x: 0, y: 0, width: 100, height: 50 };
+    const h = rect.height / 2; // 25
+    const outside: P = { x: 0, y: 100 };
+    const inside: P = { x: 0, y: 0 };
+    const res = intersection(rect, outside, inside);
+    expect(approx(res.x, 0)).toBe(true);
+    expect(approx(res.y, h)).toBe(true);
+  });
+
+  it('ensureTrulyOutside nudges near-boundary point outward', () => {
+    const rect: RectLike = { x: 0, y: 0, width: 100, height: 50 };
+    // near bottom boundary (y ~ h)
+    const near: P = { x: 0, y: rect.height / 2 - 0.2 };
+    const out = ensureTrulyOutside(rect, near, 10);
+    expect(out.y).toBeGreaterThan(rect.height / 2);
+  });
+
+  it('makeInsidePoint keeps x for vertical and y from center', () => {
+    const rect: RectLike = { x: 10, y: 5, width: 100, height: 50 };
+    const outside: P = { x: 10, y: 40 };
+    const center: P = { x: 99, y: -123 }; // center y should be used
+    const inside = makeInsidePoint(rect, outside, center);
+    expect(inside.x).toBe(outside.x);
+    expect(inside.y).toBe(center.y);
+  });
+
+  it('tryNodeIntersect returns null for wrong-side intersections', () => {
+    const rect: RectLike = { x: 0, y: 0, width: 100, height: 50 };
+    const outside: P = { x: -50, y: 0 };
+    const node = { intersect: () => ({ x: 10, y: 0 }) } as any; // right side of center
+    const res = tryNodeIntersect(node, rect, outside);
+    expect(res).toBeNull();
+  });
+
+  it('replaceEndpoint dedup removes end/start appropriately', () => {
+    const pts: P[] = [
+      { x: 0, y: 0 },
+      { x: 1, y: 1 },
+    ];
+    // remove duplicate end
+    replaceEndpoint(pts, 'end', { x: 1, y: 1 });
+    expect(pts.length).toBe(1);
+
+    const pts2: P[] = [
+      { x: 0, y: 0 },
+      { x: 1, y: 1 },
+    ];
+    // remove duplicate start
+    replaceEndpoint(pts2, 'start', { x: 0, y: 0 });
+    expect(pts2.length).toBe(1);
+  });
+});