pi/packages/tui/test/terminal.test.ts

import assert from "node:assert";
import { describe, it } from "node:test";
import { ProcessTerminal } from "../src/terminal.js";

describe("ProcessTerminal dimensions", () => {
	it("falls back to COLUMNS and LINES before default dimensions", () => {
		const previousColumnsDescriptor = Object.getOwnPropertyDescriptor(process.stdout, "columns");
		const previousRowsDescriptor = Object.getOwnPropertyDescriptor(process.stdout, "rows");
		const previousColumns = process.env.COLUMNS;
		const previousLines = process.env.LINES;

		try {
			Object.defineProperty(process.stdout, "columns", { value: undefined, configurable: true });
			Object.defineProperty(process.stdout, "rows", { value: undefined, configurable: true });
			process.env.COLUMNS = "123";
			process.env.LINES = "45";

			const terminal = new ProcessTerminal();

			assert.equal(terminal.columns, 123);
			assert.equal(terminal.rows, 45);
		} finally {
			if (previousColumnsDescriptor) {
				Object.defineProperty(process.stdout, "columns", previousColumnsDescriptor);
			} else {
				Reflect.deleteProperty(process.stdout, "columns");
			}
			if (previousRowsDescriptor) {
				Object.defineProperty(process.stdout, "rows", previousRowsDescriptor);
			} else {
				Reflect.deleteProperty(process.stdout, "rows");
			}
			if (previousColumns === undefined) {
				delete process.env.COLUMNS;
			} else {
				process.env.COLUMNS = previousColumns;
			}
			if (previousLines === undefined) {
				delete process.env.LINES;
			} else {
				process.env.LINES = previousLines;
			}
		}
	});
});