feat: 完成测试 16-17

src/utils/__tests__/sliceAnsi.test.ts

@@ -0,0 +1,108 @@
+import { mock, describe, expect, test } from "bun:test";
+
+// Mock ink/stringWidth to avoid heavy Ink import chain
+mock.module("src/ink/stringWidth.js", () => ({
+  stringWidth: (str: string) => {
+    // Simplified width calculation for test purposes
+    let width = 0;
+    for (const char of str) {
+      const code = char.codePointAt(0)!;
+      // CJK Unified Ideographs and common full-width ranges
+      if (
+        (code >= 0x4e00 && code <= 0x9fff) || // CJK
+        (code >= 0x3000 && code <= 0x303f) || // CJK Symbols
+        (code >= 0xff01 && code <= 0xff60) || // Fullwidth Forms
+        (code >= 0xf900 && code <= 0xfaff)    // CJK Compatibility
+      ) {
+        width += 2;
+      } else if (code > 0) {
+        width += 1;
+      }
+    }
+    return width;
+  },
+}));
+
+const sliceAnsi = (await import("../sliceAnsi")).default;
+
+describe("sliceAnsi", () => {
+  test("plain text slice identical to String.slice", () => {
+    expect(sliceAnsi("hello world", 0, 5)).toBe("hello");
+    expect(sliceAnsi("hello world", 6)).toBe("world");
+  });
+
+  test("slice entire string", () => {
+    expect(sliceAnsi("abc", 0)).toBe("abc");
+  });
+
+  test("empty slice (start === end)", () => {
+    expect(sliceAnsi("abc", 2, 2)).toBe("");
+  });
+
+  test("preserves ANSI color codes within slice", () => {
+    const input = "\x1b[31mred\x1b[0m normal";
+    const result = sliceAnsi(input, 0, 3);
+    expect(result).toContain("\x1b[31m");
+    expect(result).toContain("red");
+  });
+
+  test("closes opened ANSI styles at slice end", () => {
+    const input = "\x1b[31mhello world\x1b[0m";
+    const result = sliceAnsi(input, 0, 5);
+    expect(result).toContain("\x1b[31m");
+    expect(result).toContain("hello");
+    // undoAnsiCodes uses specific close codes (e.g. \x1b[39m for foreground)
+    expect(result).toMatch(new RegExp("\\x1b\\[\\d+m"));
+    // The result should start with open code and end with a close code
+    const withoutText = result.replace("hello", "");
+    // Should have at least one open and one close code
+    expect(withoutText.length).toBeGreaterThan(0);
+  });
+
+  test("slice starting mid-ANSI skips codes before start", () => {
+    const input = "\x1b[31mhello\x1b[0m \x1b[32mworld\x1b[0m";
+    const result = sliceAnsi(input, 6, 11);
+    expect(result).toContain("world");
+    expect(result).toContain("\x1b[32m");
+    expect(result).not.toContain("\x1b[31m");
+  });
+
+  test("slice of plain text from middle", () => {
+    expect(sliceAnsi("abcdefgh", 2, 5)).toBe("cde");
+  });
+
+  test("slice past end of string returns everything", () => {
+    expect(sliceAnsi("abc", 0, 100)).toBe("abc");
+  });
+
+  test("slice starting at end returns empty", () => {
+    expect(sliceAnsi("abc", 3)).toBe("");
+  });
+
+  test("handles empty string", () => {
+    expect(sliceAnsi("", 0, 5)).toBe("");
+  });
+
+  test("multiple ANSI codes nested", () => {
+    const input = "\x1b[1m\x1b[31mbold red\x1b[0m\x1b[0m";
+    const result = sliceAnsi(input, 0, 4);
+    expect(result).toContain("bold");
+    // Both styles should be opened and then closed
+    expect(result).toContain("\x1b[1m");
+    expect(result).toContain("\x1b[31m");
+  });
+
+  test("slice with no end parameter returns to end of string", () => {
+    expect(sliceAnsi("hello world", 6)).toBe("world");
+  });
+
+  test("ANSI codes at boundaries are handled correctly", () => {
+    const input = "a\x1b[31mb\x1b[0mc";
+    // "abc" visually, position: a=0, b=1, c=2
+    const result = sliceAnsi(input, 1, 2);
+    // undoAnsiCodes uses \x1b[39m for foreground reset, not \x1b[0m
+    expect(result).toContain("b");
+    expect(result).toContain("\x1b[31m");
+    expect(result).toMatch(new RegExp("\\x1b\\[\\d+m.*\\x1b\\[\\d+m")); // open + close codes
+  });
+});