tests: add unit test files and improve test coverage by nberlette · Pull Request #7 · nberlette/tui

nberlette · 2026-03-12T00:42:43Z

tests(utils): add more test cases for internal utils
tests(utils): add ansi_codes and component utils tests
fix(tests): move misplaced @ts-expect-error comment to the correct line
tests(event-emitter): add EventEmitter test cases
tests(components): add unit tests for Component APIs
tests(canvas): add Canvas API unit tests
tests: add text fixtures module
config(gitignore): add .coverage dir to .gitignore
chore: update lockfile
tests: add smoke tests for mod.ts barrel entry points
tests(input): add input test cases
tests: add unit tests for theme, layout, and view APIs
tests(signals): add unit tests for signals APIs
tests(stdio): add stdio unit tests
chore: remove contributing.md since it was practically empty
config: add tasks to deno.json

Copilot

Pull request overview

Adds a broad set of new unit tests across the library (signals, stdio, canvas, components, input, layout/theme/view) and introduces local deno task helpers to make running tests/lint/fmt (and collecting coverage) easier.

Changes:

Added many new unit tests and a shared tests/fixtures.ts helper to improve coverage across core modules.
Added smoke tests for barrel exports (e.g., mod.ts, src/*/mod.ts).
Updated repo config: ignore coverage output, add deno task entries, and update deno.lock (Node typings).

Reviewed changes

Copilot reviewed 35 out of 37 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tests/view.test.ts	Adds View constructor behavior tests.
tests/utils/strings.test.ts	Expands string utility coverage.
tests/utils/sorted_array.test.ts	Adds more SortedArray behavior assertions.
tests/utils/numbers.test.ts	Restructures/expands numbers utility tests.
tests/utils/component.test.ts	Adds tests for component-related utils.
tests/utils/async.test.ts	Expands `sleep()` tests (includes timing + concurrency).
tests/utils/ansi_codes.test.ts	Adds ANSI constants/moveCursor tests.
tests/theme.test.ts	Adds tests for theme helpers and Theme factories.
tests/stdio/stdout.test.ts	Adds Stdout adapter + writable stream tests.
tests/stdio/stdin.test.ts	Adds Stdin adapter + readable stream tests.
tests/stdio/stderr.test.ts	Adds Stderr adapter + writable stream tests.
tests/stdio/mod.test.ts	Adds stdio barrel export smoke test.
tests/stdio/console_size.test.ts	Adds console size resolution/fallback tests.
tests/signals/signalify.test.ts	Adds signalify wrapping behavior tests.
tests/signals/mod.test.ts	Adds signals barrel export smoke test.
tests/signals/flusher.test.ts	Adds Flusher dependency/flush behavior test.
tests/signals/effect.test.ts	Adds Effect/effect lifecycle behavior tests.
tests/signals/dependency_tracking.test.ts	Adds dependency tracking/optimization tests.
tests/signals/computed.test.ts	Adds Computed/computed behavior tests.
tests/mod.test.ts	Adds root `mod.ts` export smoke test.
tests/layout.test.ts	Adds public layout API tests and error assertions.
tests/input.test.ts	Adds keyboard/mouse/buffer decoding tests.
tests/fixtures.ts	Introduces shared test fixtures (fake root/canvas/stdout helpers).
tests/event_emitter.test.ts	Expands EventEmitter tests (cleanup/off behavior).
tests/components/text.test.ts	Adds Text component draw/sizing tests.
tests/components/mod.test.ts	Adds components barrel export smoke test.
tests/components/box.test.ts	Adds Box component draw wiring test.
tests/component.test.ts	Adds Component interaction + drawn object visibility tests.
tests/canvas/text.test.ts	Adds TextObject sizing + multi-codepoint tests.
tests/canvas/renderable.test.ts	Adds Renderable rerender/out-of-bounds tests.
tests/canvas/mod.test.ts	Adds canvas barrel export smoke test.
tests/canvas/core.test.ts	Adds Canvas intersection + render behavior tests.
tests/canvas/box.test.ts	Adds BoxObject rerender + omit-cell behavior test.
deno.lock	Updates lockfile (includes Node typings).
deno.json	Adds convenience tasks for test/lint/fmt and coverage output.
CONTRIBUTING.md	Removes (previously minimal/empty) contributing guide.
.gitignore	Ignores `.coverage` output directory.

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Copilot · 2026-03-12T00:47:46Z

tests/stdio/console_size.test.ts

+    const original = globalThis.process;
+    Object.defineProperty(globalThis, "process", {
+      value: {
+        stdout: { columns: 0, rows: 0, getWindowSize: undefined },
+        stderr: { columns: 0, rows: 0 },
+        env: { COLUMNS: "90", LINES: "33" },
+      },
+      configurable: true,
+    });
+
+    try {
+      assertEquals(consoleSize(), { columns: 90, rows: 33 });
+    } finally {
+      Object.defineProperty(globalThis, "process", {
+        value: original,
+        configurable: true,
+      });
+    }


Same globalThis.process restoration issue as above: this finally block redefines the property rather than restoring/removing it, which can pollute global state across tests. Consider capturing and restoring the original property descriptor (or deleting the property if it was originally absent).

Copilot · 2026-03-12T00:47:46Z

tests/stdio/console_size.test.ts

+    const defaults = { columns: 7, rows: 9 };
+    Object.defineProperty(globalThis, "process", {
+      get() {
+        throw new Error("boom");
+      },
+      configurable: true,
+    });
+
+    try {
+      const size = consoleSize(defaults);
+      assertEquals(size, defaults);
+      assertNotStrictEquals(size, defaults);
+    } finally {
+      Object.defineProperty(globalThis, "process", {
+        value: original,
+        configurable: true,
+      });
+    }


After installing a throwing getter for globalThis.process, the finally block should restore the original descriptor or remove the property if it wasn't originally present. Replacing it with { value: original } changes the semantics for subsequent tests (e.g., "process" in globalThis).

Copilot · 2026-03-12T00:47:46Z

tests/fixtures.ts

+import { Canvas } from "../src/canvas/canvas.ts";
+import { EventEmitter } from "../src/event_emitter.ts";
+import { Signal } from "../src/signals/signal.ts";


This new file is missing the repository’s required license header (// Copyright 2023 Im-Beast. MIT license.). CI runs a header-check step for .ts files (excluding only deps.ts), so this will be flagged/rewritten during CI.

Copilot · 2026-03-12T00:47:47Z

tests/utils/async.test.ts

+  await it("is a function", () => {
+    assert.strict(typeof sleep === "function");
+  });


node:assert's default import doesn't have an assert.strict(...) assertion function (it's an object / namespace). This call will throw at runtime; use assert.ok(...) / assert.strictEqual(..., true) or import from node:assert/strict instead.

Copilot · 2026-03-12T00:47:47Z

tests/utils/async.test.ts

+  await it("returns a promise", () => {
+    const result = sleep(100);
+    assert.strict(isPromise(result), "Expected sleep to return a promise");
+  });


assert.strict(...) is not a valid assertion on the default node:assert import, so this check will throw. Use assert.ok(isPromise(result)), assert.strictEqual(isPromise(result), true), or switch to node:assert/strict.

Copilot · 2026-03-12T00:47:47Z

tests/stdio/console_size.test.ts

+    const original = globalThis.process;
+    Object.defineProperty(globalThis, "process", {
+      value: {
+        stdout: { columns: 111, rows: 22 },
+        stderr: { columns: 1, rows: 1 },
+        env: {},
+      },
+      configurable: true,
+    });
+
+    try {
+      assertEquals(consoleSize(), { columns: 111, rows: 22 });
+    } finally {
+      Object.defineProperty(globalThis, "process", {
+        value: original,
+        configurable: true,
+      });
+    }


This test mutates globalThis.process, but the restore path always re-defines the property (even when it was originally absent/undefined). That can leak state into later tests because "process" in globalThis becomes true. Track whether process was originally an own property and restore by deleting it when it didn't exist, or restore the original property descriptor.

nberlette added 16 commits March 11, 2026 15:54

tests(utils): add more test cases for internal utils

461f087

tests(utils): add ansi_codes and component utils tests

367bb21

fix(tests): move misplaced @ts-expect-error comment to the correct line

9a48602

tests(event-emitter): add EventEmitter test cases

f20e34c

tests(components): add unit tests for Component APIs

e22b4e3

tests(canvas): add Canvas API unit tests

f89ed78

tests: add text fixtures module

e699b52

config(gitignore): add .coverage dir to .gitignore

591b5fb

chore: update lockfile

8e76f89

tests: add smoke tests for mod.ts barrel entry points

c77aff3

tests(input): add input test cases

aaf8100

tests: add unit tests for theme, layout, and view APIs

25f370e

tests(signals): add unit tests for signals APIs

d22c0e6

tests(stdio): add stdio unit tests

fc41192

chore: remove contributing.md since it was practically empty

2f95e68

config: add tasks to deno.json

fc3a132

nberlette added the tests Related to unit tests label Mar 12, 2026

Copilot AI review requested due to automatic review settings March 12, 2026 00:42

nberlette self-assigned this Mar 12, 2026

Copilot started reviewing on behalf of nberlette March 12, 2026 00:43 View session

nberlette merged commit b81680b into main Mar 12, 2026
2 of 4 checks passed

nberlette deleted the tests branch March 12, 2026 00:43

Copilot AI reviewed Mar 12, 2026

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tests: add unit test files and improve test coverage#7

tests: add unit test files and improve test coverage#7
nberlette merged 16 commits intomainfrom
tests

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