feat(tui): make select list column sizing configurable (#2154)

* feat(tui): make select list layout configurable

* feat(tui): tune select list column sizing

* test(tui): fix select list alignment assertions

packages/tui/test/select-list.test.ts

@@ -1,6 +1,7 @@
 import assert from "node:assert";
 import { describe, it } from "node:test";
 import { SelectList } from "../src/components/select-list.js";
+import { visibleWidth } from "../src/utils.js";
 
 const testTheme = {
 	selectedPrefix: (text: string) => text,
@@ -10,6 +11,12 @@ const testTheme = {
 	noMatch: (text: string) => text,
 };
 
+const visibleIndexOf = (line: string, text: string): number => {
+	const index = line.indexOf(text);
+	assert.notEqual(index, -1);
+	return visibleWidth(line.slice(0, index));
+};
+
 describe("SelectList", () => {
 	it("normalizes multiline descriptions to single line", () => {
 		const items = [
@@ -27,4 +34,83 @@ describe("SelectList", () => {
 		assert.ok(!rendered[0].includes("\n"));
 		assert.ok(rendered[0].includes("Line one Line two Line three"));
 	});
+
+	it("keeps descriptions aligned when the primary text is truncated", () => {
+		const items = [
+			{ value: "short", label: "short", description: "short description" },
+			{
+				value: "very-long-command-name-that-needs-truncation",
+				label: "very-long-command-name-that-needs-truncation",
+				description: "long description",
+			},
+		];
+
+		const list = new SelectList(items, 5, testTheme);
+		const rendered = list.render(80);
+
+		assert.equal(visibleIndexOf(rendered[0], "short description"), visibleIndexOf(rendered[1], "long description"));
+	});
+
+	it("uses the configured minimum primary column width", () => {
+		const items = [
+			{ value: "a", label: "a", description: "first" },
+			{ value: "bb", label: "bb", description: "second" },
+		];
+
+		const list = new SelectList(items, 5, testTheme, {
+			minPrimaryColumnWidth: 12,
+			maxPrimaryColumnWidth: 20,
+		});
+		const rendered = list.render(80);
+
+		assert.equal(rendered[0].indexOf("first"), 14);
+		assert.equal(rendered[1].indexOf("second"), 14);
+	});
+
+	it("uses the configured maximum primary column width", () => {
+		const items = [
+			{
+				value: "very-long-command-name-that-needs-truncation",
+				label: "very-long-command-name-that-needs-truncation",
+				description: "first",
+			},
+			{ value: "short", label: "short", description: "second" },
+		];
+
+		const list = new SelectList(items, 5, testTheme, {
+			minPrimaryColumnWidth: 12,
+			maxPrimaryColumnWidth: 20,
+		});
+		const rendered = list.render(80);
+
+		assert.equal(visibleIndexOf(rendered[0], "first"), 22);
+		assert.equal(visibleIndexOf(rendered[1], "second"), 22);
+	});
+
+	it("allows overriding primary truncation while preserving description alignment", () => {
+		const items = [
+			{
+				value: "very-long-command-name-that-needs-truncation",
+				label: "very-long-command-name-that-needs-truncation",
+				description: "first",
+			},
+			{ value: "short", label: "short", description: "second" },
+		];
+
+		const list = new SelectList(items, 5, testTheme, {
+			minPrimaryColumnWidth: 12,
+			maxPrimaryColumnWidth: 12,
+			truncatePrimary: ({ text, maxWidth }) => {
+				if (text.length <= maxWidth) {
+					return text;
+				}
+
+				return `${text.slice(0, Math.max(0, maxWidth - 1))}…`;
+			},
+		});
+		const rendered = list.render(80);
+
+		assert.ok(rendered[0].includes("…"));
+		assert.equal(visibleIndexOf(rendered[0], "first"), visibleIndexOf(rendered[1], "second"));
+	});
 });