fix: Fix the infinite loop caused by equalizeSegments in special cases (#129)

* fix: Fix the infinite loop caused by equalizeSegments in special cases

* fix: code style

* ci: add tests

* chore: update version

Author: lxfu1

__tests__/unit/path/equalize-segments.spec.ts

@@ -98,4 +98,64 @@ describe('equalize segments', () => {
       ],
     ]);
   });
+  it('should not recurse infinitely if segments cannot be split', () => {
+    const path1: PathArray = [
+      ['M', 0, 0],
+      ['L', 1, 1], // 非常短的线段，不满足 split 条件
+    ];
+    const path2: PathArray = [
+      ['M', 0, 0],
+      ['L', 10, 10],
+      ['L', 20, 20],
+      ['L', 30, 30],
+    ];
+
+    const result = equalizeSegments(path1, path2);
+    // 不是一定相等，因为可能无法拆分，重点是不会死循环
+    expect(Array.isArray(result)).toBe(true);
+    expect(result.length).toBe(2);
+  });
+  it('should split cubic bezier curves correctly', () => {
+    const path1: PathArray = [
+      ['M', 0, 0],
+      ['C', 30, 30, 60, 30, 100, 0],
+    ];
+    const path2: PathArray = [
+      ['M', 0, 0],
+      ['C', 20, 20, 40, 20, 60, 0],
+      ['C', 70, -20, 90, -20, 100, 0],
+    ];
+
+    const result = equalizeSegments(path1, path2);
+    expect(result[0].length).toBe(result[1].length);
+  });
+  it('should equalizeSegments for complex multi-segment paths', () => {
+    const path1: PathArray = [
+      ['M', 0, 0],
+      ['L', 50, 0],
+      ['C', 60, 10, 70, 10, 80, 0],
+    ];
+    const path2: PathArray = [
+      ['M', 0, 0],
+      ['L', 20, 0],
+      ['L', 40, 0],
+      ['L', 60, 0],
+      ['C', 65, 5, 75, 5, 80, 0],
+    ];
+
+    const result = equalizeSegments(path1, path2);
+    expect(result[0].length).toBe(result[1].length);
+  });
+  it('should terminate recursion at max depth', () => {
+    const path1: PathArray = [
+      ['M', 0, 0],
+      ['L', 1, 1],
+    ];
+    // @ts-ignore
+    const path2: PathArray = Array.from({ length: 20 }, (_, i) => ['L', i, i + 1]) as PathArray;
+    path2.unshift(['M', 0, 0]);
+
+    const result = equalizeSegments(path1, path2);
+    expect(result.length).toBe(2);
+  });
 });

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@antv/util",
-  "version": "3.3.10",
+  "version": "3.3.11",
   "license": "MIT",
   "sideEffects": false,
   "main": "lib/index.js",

src/path/util/equalize-segments.ts

@@ -4,6 +4,8 @@ import { segmentCubicFactory } from './segment-cubic-factory';
 
 type SplitArray = [number, number, number, number, number, number, number, number, number];
 
+const MAX_RECURSION_DEPTH = 50;
+
 function splitCubic(pts: SplitArray, t = 0.5): [CurveArray, CurveArray] {
   const p0 = pts.slice(0, 2) as [number, number];
   const p1 = pts.slice(2, 4) as [number, number];
@@ -61,7 +63,11 @@ function getCurveArray(segments: PathArray) {
   });
 }
 
-export function equalizeSegments(path1: PathArray, path2: PathArray, TL?: number): CurveArray[] {
+export function equalizeSegments(path1: PathArray, path2: PathArray, TL?: number, depth = 0): CurveArray[] {
+  if (depth > MAX_RECURSION_DEPTH) {
+    console.warn('Maximum recursion depth reached in equalizeSegments');
+    return [path1, path2] as CurveArray[];
+  }
   const c1 = getCurveArray(path1);
   const c2 = getCurveArray(path2);
   const L1 = c1.length;
@@ -87,5 +93,5 @@ export function equalizeSegments(path1: PathArray, path2: PathArray, TL?: number
           .flat(),
   ) as CurveArray[];
 
-  return result[0].length === result[1].length ? result : equalizeSegments(result[0], result[1], tl);
+  return result[0].length === result[1].length ? result : equalizeSegments(result[0], result[1], tl, depth + 1);
 }