oh-my-pi/packages/coding-agent/test/tiny-text.test.ts

import { describe, expect, it } from "bun:test";
import {
	formatTitleUserMessage,
	isLowSignalTitleInput,
	MAX_TITLE_INPUT_CHARS,
	NO_TITLE_SENTINEL,
	normalizeGeneratedTitle,
	prepareTitleInput,
	stripCodeBlocks,
} from "@oh-my-pi/pi-coding-agent/tiny/text";

describe("stripCodeBlocks", () => {
	it("drops fenced code blocks but keeps the surrounding prose", () => {
		const message = "lets plan a setup screen together.\n```\nsome mockup\n```\nit should only show once.";
		const stripped = stripCodeBlocks(message);
		expect(stripped).not.toContain("some mockup");
		expect(stripped).toContain("plan a setup screen");
		expect(stripped).toContain("it should only show once.");
	});

	it("removes literal noise inside a pasted mockup (the reported regression)", () => {
		// A small title model titled this session "Setup Screen for Claude Code v2.1.158"
		// because the version string lived inside the fenced mockup.
		const message =
			"lets plan a setup screen together.\nSomething like\n```\nWelcome to Claude Code v2.1.158\n[splash]\n1. Auto\n2. Dark mode\n```\nsteps: pick provider, pick theme";
		const stripped = stripCodeBlocks(message);
		expect(stripped).not.toContain("Claude Code v2.1.158");
		expect(stripped).toContain("pick provider, pick theme");
	});

	it("handles an unterminated fence by stripping to end of message", () => {
		const stripped = stripCodeBlocks("describe the bug\n```\nthrows here and never closes");
		expect(stripped).toBe("describe the bug");
	});

	it("keeps inline code (single backticks) as high-signal context", () => {
		const stripped = stripCodeBlocks("wire up the `/login` provider step");
		expect(stripped).toContain("`/login`");
	});

	it("falls back to the original when the message is essentially only a code block", () => {
		const message = "```python\ndef merge_sort(a):\n    return a\n```";
		expect(stripCodeBlocks(message)).toBe(message);
	});

	it("returns prose unchanged when there is no code block", () => {
		expect(stripCodeBlocks("Investigate the resolver")).toBe("Investigate the resolver");
	});
});

describe("prepareTitleInput", () => {
	it("strips code blocks before bounding length", () => {
		const message = `intro prose ${"x".repeat(MAX_TITLE_INPUT_CHARS)}\n\`\`\`\n${"y".repeat(5000)}\n\`\`\``;
		const prepared = prepareTitleInput(message);
		expect(prepared).not.toContain("yyyy");
		expect(prepared.length).toBeLessThanOrEqual(MAX_TITLE_INPUT_CHARS + 1); // +1 for the ellipsis
	});
});

describe("formatTitleUserMessage", () => {
	it("wraps stripped content in user-message tags", () => {
		const formatted = formatTitleUserMessage("plan a thing\n```\nnoise\n```");
		expect(formatted.startsWith("<user-message>\n")).toBe(true);
		expect(formatted.endsWith("\n</user-message>")).toBe(true);
		expect(formatted).toContain("plan a thing");
		expect(formatted).not.toContain("noise");
	});
});

describe("normalizeGeneratedTitle", () => {
	it("strips surrounding quotes and trailing punctuation but preserves casing", () => {
		expect(normalizeGeneratedTitle('"Investigate the resolver"')).toBe("Investigate the resolver");
		expect(normalizeGeneratedTitle("Investigate the resolver.")).toBe("Investigate the resolver");
	});

	it("preserves the model's sentence/proper-noun casing without title-casing", () => {
		// Regression: the normalizer used to force Title Case, capitalizing function
		// words ("for" → "For") and clobbering proper nouns the model cased right.
		expect(normalizeGeneratedTitle("Docker client/daemon for TinyVMM")).toBe("Docker client/daemon for TinyVMM");
	});

	it("preserves model casing verbatim when no source message is provided", () => {
		// Without the user's message there is nothing to reconcile against, so the
		// model's output is kept as-is (no title-casing, no flattening).
		expect(normalizeGeneratedTitle("Docker client/dAemon for tinyvmm")).toBe("Docker client/dAemon for tinyvmm");
	});

	it("treats the bare none sentinel as no title (case/punctuation-insensitive)", () => {
		expect(NO_TITLE_SENTINEL).toBe("none");
		expect(normalizeGeneratedTitle("none")).toBeNull();
		expect(normalizeGeneratedTitle("None.")).toBeNull();
		expect(normalizeGeneratedTitle('"none"')).toBeNull();
	});

	it("keeps a title that merely contains the word none", () => {
		expect(normalizeGeneratedTitle("Explain Python None keyword")).toBe("Explain Python None keyword");
	});

	it("returns null for empty or whitespace-only output", () => {
		expect(normalizeGeneratedTitle("")).toBeNull();
		expect(normalizeGeneratedTitle("   ")).toBeNull();
		expect(normalizeGeneratedTitle(null)).toBeNull();
	});
});

describe("normalizeGeneratedTitle source-aware casing", () => {
	it("flattens a stray interior capital the user never typed", () => {
		// "dAemon" is a model artifact; the user's message has no such token.
		expect(normalizeGeneratedTitle("Docker client/dAemon for tinyvmm", "build a docker daemon for tinyvmm")).toBe(
			"Docker client/daemon for tinyvmm",
		);
	});

	it("keeps odd casing the user typed verbatim", () => {
		expect(normalizeGeneratedTitle("Use the dAemon API", "the dAemon name is intentional")).toBe(
			"Use the dAemon API",
		);
	});

	it("restores a proper noun's casing from the user's message", () => {
		// Tiny model flattened "TinyVMM" → "tinyvmm"; the user wrote it distinctively.
		expect(normalizeGeneratedTitle("Set up tinyvmm daemon", "please configure TinyVMM")).toBe(
			"Set up TinyVMM daemon",
		);
	});

	it("leaves PascalCase proper nouns the model produced even when absent from source", () => {
		expect(normalizeGeneratedTitle("Fix GitHub OAuth flow", "fix the login redirect")).toBe("Fix GitHub OAuth flow");
	});

	it("does not lowercase the model's correct casing when the user typed it lower", () => {
		// Source "tinyvmm" is not distinctive, so it must not pull "TinyVMM" down.
		expect(normalizeGeneratedTitle("Improve TinyVMM startup", "improve tinyvmm startup")).toBe(
			"Improve TinyVMM startup",
		);
	});

	it("a source word that merely starts a sentence does not force mid-title casing", () => {
		// Regression: leading "For" in the message must not capitalize "for" in the title.
		expect(normalizeGeneratedTitle("Add retry to the for loop", "For reliability, add retries")).toBe(
			"Add retry to the for loop",
		);
	});
});

describe("isLowSignalTitleInput", () => {
	it("treats greetings and acknowledgements as low signal (defer)", () => {
		for (const msg of [
			"hi",
			"Hi!",
			"hey there",
			"hello :)",
			"good morning",
			"thanks!",
			"ok cool",
			"yo",
			"test",
			"ping",
		]) {
			expect(isLowSignalTitleInput(msg)).toBe(true);
		}
	});

	it("treats empty / punctuation / emoji-only input as low signal", () => {
		expect(isLowSignalTitleInput("")).toBe(true);
		expect(isLowSignalTitleInput("   ")).toBe(true);
		expect(isLowSignalTitleInput("👋👋")).toBe(true);
		expect(isLowSignalTitleInput("?!")).toBe(true);
		expect(isLowSignalTitleInput("42")).toBe(true);
	});

	it("treats messages with a real task as title-worthy", () => {
		for (const msg of [
			"fix the resolver bug",
			"deploy",
			"hi, can you fix the login flow",
			"add a test for the parser",
			"what does this regex do",
		]) {
			expect(isLowSignalTitleInput(msg)).toBe(false);
		}
	});
});