clanker-agent/packages/tui/test/truncated-text.test.ts

import assert from "node:assert";
import { describe, it } from "node:test";
import { Chalk } from "chalk";
import { TruncatedText } from "../src/components/truncated-text.js";
import { visibleWidth } from "../src/utils.js";

// Force full color in CI so ANSI assertions are deterministic
const chalk = new Chalk({ level: 3 });

describe("TruncatedText component", () => {
  it("pads output lines to exactly match width", () => {
    const text = new TruncatedText("Hello world", 1, 0);
    const lines = text.render(50);

    // Should have exactly one content line (no vertical padding)
    assert.strictEqual(lines.length, 1);

    // Line should be exactly 50 visible characters
    const visibleLen = visibleWidth(lines[0]);
    assert.strictEqual(visibleLen, 50);
  });

  it("pads output with vertical padding lines to width", () => {
    const text = new TruncatedText("Hello", 0, 2);
    const lines = text.render(40);

    // Should have 2 padding lines + 1 content line + 2 padding lines = 5 total
    assert.strictEqual(lines.length, 5);

    // All lines should be exactly 40 characters
    for (const line of lines) {
      assert.strictEqual(visibleWidth(line), 40);
    }
  });

  it("truncates long text and pads to width", () => {
    const longText =
      "This is a very long piece of text that will definitely exceed the available width";
    const text = new TruncatedText(longText, 1, 0);
    const lines = text.render(30);

    assert.strictEqual(lines.length, 1);

    // Should be exactly 30 characters
    assert.strictEqual(visibleWidth(lines[0]), 30);

    // Should contain ellipsis
    const stripped = lines[0].replace(/\x1b\[[0-9;]*m/g, "");
    assert.ok(stripped.includes("..."));
  });

  it("preserves ANSI codes in output and pads correctly", () => {
    const styledText = `${chalk.red("Hello")} ${chalk.blue("world")}`;
    const text = new TruncatedText(styledText, 1, 0);
    const lines = text.render(40);

    assert.strictEqual(lines.length, 1);

    // Should be exactly 40 visible characters (ANSI codes don't count)
    assert.strictEqual(visibleWidth(lines[0]), 40);

    // Should preserve the color codes
    assert.ok(lines[0].includes("\x1b["));
  });

  it("truncates styled text and adds reset code before ellipsis", () => {
    const longStyledText = chalk.red(
      "This is a very long red text that will be truncated",
    );
    const text = new TruncatedText(longStyledText, 1, 0);
    const lines = text.render(20);

    assert.strictEqual(lines.length, 1);

    // Should be exactly 20 visible characters
    assert.strictEqual(visibleWidth(lines[0]), 20);

    // Should contain reset code before ellipsis
    assert.ok(lines[0].includes("\x1b[0m..."));
  });

  it("handles text that fits exactly", () => {
    // With paddingX=1, available width is 30-2=28
    // "Hello world" is 11 chars, fits comfortably
    const text = new TruncatedText("Hello world", 1, 0);
    const lines = text.render(30);

    assert.strictEqual(lines.length, 1);
    assert.strictEqual(visibleWidth(lines[0]), 30);

    // Should NOT contain ellipsis
    const stripped = lines[0].replace(/\x1b\[[0-9;]*m/g, "");
    assert.ok(!stripped.includes("..."));
  });

  it("handles empty text", () => {
    const text = new TruncatedText("", 1, 0);
    const lines = text.render(30);

    assert.strictEqual(lines.length, 1);
    assert.strictEqual(visibleWidth(lines[0]), 30);
  });

  it("stops at newline and only shows first line", () => {
    const multilineText = "First line\nSecond line\nThird line";
    const text = new TruncatedText(multilineText, 1, 0);
    const lines = text.render(40);

    assert.strictEqual(lines.length, 1);
    assert.strictEqual(visibleWidth(lines[0]), 40);

    // Should only contain "First line"
    const stripped = lines[0].replace(/\x1b\[[0-9;]*m/g, "").trim();
    assert.ok(stripped.includes("First line"));
    assert.ok(!stripped.includes("Second line"));
    assert.ok(!stripped.includes("Third line"));
  });

  it("truncates first line even with newlines in text", () => {
    const longMultilineText =
      "This is a very long first line that needs truncation\nSecond line";
    const text = new TruncatedText(longMultilineText, 1, 0);
    const lines = text.render(25);

    assert.strictEqual(lines.length, 1);
    assert.strictEqual(visibleWidth(lines[0]), 25);

    // Should contain ellipsis and not second line
    const stripped = lines[0].replace(/\x1b\[[0-9;]*m/g, "");
    assert.ok(stripped.includes("..."));
    assert.ok(!stripped.includes("Second line"));
  });
});