[READ-ONLY] Mirror of https://github.com/bombshell-dev/tty. Platform independent 2D layout engine for terminal applications based on Clay
test: failing repro for wide-char-overlay
Nate Moore
(Jun 4, 2026, 12:33 AM -0500)
352cb27b
d75fb4b6
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test/wide-char-overlay.test.ts
+54
test/wide-char-overlay.test.ts
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import { beforeEach, describe, expect, it } from "./suite.ts";
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import { createTerm, type Term } from "../term.ts";
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import { close, fixed, grow, open, text } from "../ops.ts";
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import { print } from "./print.ts";
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const decode = (b: Uint8Array) => new TextDecoder().decode(b);
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describe("wide-char trailing overlay", () => {
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let term: Term;
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beforeEach(async () => {
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term = await createTerm({ width: 12, height: 1 });
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});
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it("overlay on a wide char's trailing column clears the orphaned lead to a space", () => {
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// X is floated onto col 1, the trailing column of 你 (cols 0-1).
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let out = print(
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decode(
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term.render([
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open("root", { layout: { width: grow(), height: grow() } }),
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text("你好"),
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open("ov", {
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floating: { x: 1, y: 0, attachTo: 3 },
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layout: { width: fixed(1), height: fixed(1) },
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}),
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text("X"),
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close(),
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close(),
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]).output,
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),
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12,
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1,
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);
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// pins: half-overwritten 你 collapses to a space, X lands at col 1, 好 untouched at 2-3.
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expect(out).toBe(" X好 ");
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});
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it("emits an explicit byte for an overlay landing on a placeholder column", () => {
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let ansi = decode(
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term.render([
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open("root", { layout: { width: grow(), height: grow() } }),
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text("你好"),
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open("ov", {
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floating: { x: 1, y: 0, attachTo: 3 },
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layout: { width: fixed(1), height: fixed(1) },
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}),
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text("X"),
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close(),
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close(),
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]).output,
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);
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// pins: the overlay glyph reaches the byte stream rather than being swallowed by the column skip.
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expect(ansi).toContain("X");
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});
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});