feat: Initial prototype

tests/figlet.test.mjs

@@ -0,0 +1,84 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import {readFile, readdir} from 'node:fs/promises';
+import {fonts} from '../font-catalog.js';
+import {render, registerFont, renderLoaded, resolveFont, FONT_CACHE} from '../renderer.js';
+
+test('catalog includes every bundled FIGlet font', async () => {
+    const files = await readdir(new URL('../fonts/figlet/', import.meta.url));
+    assert.deepEqual(fonts, files.filter(file => file.endsWith('.flf')).map(file => file.slice(0, -4)).sort());
+});
+
+for (const font of fonts) {
+    test(`renders ${font} from its local font file`, async () => {
+        registerFont(font, await readFile(new URL(`../fonts/figlet/${font}.flf`, import.meta.url), 'utf8'));
+        const art = renderLoaded('Hello World! 123', font);
+        assert.equal(typeof art, 'string');
+        assert.match(art, /\S/);
+    });
+}
+
+test('Standard preserves lowercase lettering and the familiar FIGlet shape', () => {
+    assert.equal(renderLoaded('Hi', 'Standard'), [
+        '  _   _ _ ', ' | | | (_)', ' | |_| | |', ' |  _  | |', ' |_| |_|_|',
+    ].join('\n'));
+});
+
+test('old lowercase font links resolve to their library names', () => {
+    for (const [name, expected] of [['standard', 'Standard'], ['slant', 'Slant'], ['block', 'Block'], ['banner', 'Banner'], ['compact', 'compact'], ['unknown', 'Standard']]) {
+        assert.equal(resolveFont(name), expected);
+    }
+});
+
+test('missing font requests can be retried', async () => {
+    const originalFetch = globalThis.fetch;
+    const data = await readFile(new URL('../fonts/figlet/Standard.flf', import.meta.url), 'utf8');
+    const figlet = (await import('../vendor/figlet.js')).default;
+    delete figlet.figFonts.Standard;
+    try {
+        globalThis.fetch = async () => new Response('', {status: 404});
+        await assert.rejects(render('Hi', 'Standard'), /Cannot load font/);
+        globalThis.fetch = async () => new Response(data);
+        assert.match(await render('Hi', 'Standard'), /\S/);
+    } finally {
+        globalThis.fetch = originalFetch;
+    }
+});
+
+test('caches only selected fonts and reuses them when offline', async () => {
+    const originalFetch = globalThis.fetch;
+    const originalCaches = globalThis.caches;
+    const entries = new Map();
+    const figlet = (await import('../vendor/figlet.js')).default;
+    for (const font of ['Standard', 'Slant', 'Small']) delete figlet.figFonts[font];
+    try {
+        globalThis.caches = {
+            async open(name) {
+                assert.equal(name, FONT_CACHE);
+                return {
+                    async match(url) { return entries.get(url)?.clone(); },
+                    async put(url, response) { entries.set(url, response.clone()); },
+                };
+            },
+        };
+        globalThis.fetch = async url => new Response(await readFile(new URL(url), 'utf8'));
+        await render('Hello', 'Standard');
+        await render('Hello', 'Slant');
+        assert.equal(entries.size, 2);
+        assert.ok([...entries.keys()].every(url => /\/(Standard|Slant)\.flf$/.test(url)));
+        delete figlet.figFonts.Standard;
+        globalThis.fetch = async () => { throw new Error('Offline'); };
+        assert.match(await render('Offline', 'Standard'), /\S/);
+        await assert.rejects(render('Offline', 'Small'), /Offline/);
+        assert.equal(entries.size, 2);
+    } finally {
+        globalThis.fetch = originalFetch;
+        if (originalCaches === undefined) delete globalThis.caches;
+        else globalThis.caches = originalCaches;
+    }
+});
+
+test('rejects unknown fonts and overlong input', async () => {
+    await assert.rejects(render('Hello', 'unknown'), /Unknown/);
+    await assert.rejects(render('x'.repeat(501)), /too long/);
+});