feat: X API Cost Crisis Alert Chrome extension MVP with cost calculator, 8 alternatives, and 12 passing tests

test/alternatives.test.ts

@@ -0,0 +1,85 @@
+import { describe, it } from 'node:test'
+import assert from 'node:assert'
+import { calculateXCost, getAlternativesForUseCase, xApiAlternatives } from '../src/data/alternatives.js'
+
+describe('calculateXCost', () => {
+  it('returns Free tier for 0 reads and 0 writes', () => {
+    const result = calculateXCost(0, 0)
+    assert.strictEqual(result.tier, 'Free')
+    assert.strictEqual(result.cost, 0)
+    assert.strictEqual(result.overage, false)
+  })
+
+  it('returns Free tier for 1500 reads and 0 writes', () => {
+    const result = calculateXCost(1500, 0)
+    assert.strictEqual(result.tier, 'Free')
+    assert.strictEqual(result.cost, 0)
+  })
+
+  it('returns Basic tier for 5000 reads and 100 writes', () => {
+    const result = calculateXCost(5000, 100)
+    assert.strictEqual(result.tier, 'Basic')
+    assert.strictEqual(result.cost, 100)
+  })
+
+  it('returns Pro tier for 500000 reads and 100000 writes', () => {
+    const result = calculateXCost(500000, 100000)
+    assert.strictEqual(result.tier, 'Pro')
+    assert.strictEqual(result.cost, 5000)
+  })
+
+  it('returns Enterprise tier for 5M reads and 500K writes', () => {
+    const result = calculateXCost(5000000, 500000)
+    assert.strictEqual(result.tier, 'Enterprise')
+    assert.strictEqual(result.cost, 42000)
+  })
+
+  it('returns Enterprise+ with overage for 25M reads', () => {
+    const result = calculateXCost(25000000, 1000000)
+    assert.strictEqual(result.tier, 'Enterprise+')
+    assert.strictEqual(result.overage, true)
+    assert.strictEqual(result.cost, 92000)
+  })
+})
+
+describe('getAlternativesForUseCase', () => {
+  it('returns RSS alternatives for rss filter', () => {
+    const alts = getAlternativesForUseCase('rss')
+    assert.ok(alts.length > 0)
+    assert.ok(alts.some(a => a.name.includes('RSSHub')))
+  })
+
+  it('returns scraping alternatives for scraping filter', () => {
+    const alts = getAlternativesForUseCase('scraping')
+    assert.ok(alts.some(a => a.name.includes('TweetScraper')))
+  })
+
+  it('returns default alternatives for unknown filter', () => {
+    const alts = getAlternativesForUseCase('unknown-category')
+    assert.ok(alts.length > 0)
+  })
+})
+
+describe('xApiAlternatives data', () => {
+  it('has at least 8 alternatives', () => {
+    assert.ok(xApiAlternatives.length >= 8)
+  })
+
+  it('every alternative has required fields', () => {
+    for (const alt of xApiAlternatives) {
+      assert.ok(alt.name, 'name is required')
+      assert.ok(alt.website, 'website is required')
+      assert.ok(alt.freeTier, 'freeTier is required')
+      assert.ok(alt.paidTier, 'paidTier is required')
+      assert.ok(alt.description, 'description is required')
+      assert.ok(alt.features.length > 0, 'features must not be empty')
+      assert.ok(alt.bestFor, 'bestFor is required')
+    }
+  })
+
+  it('all websites are valid URLs', () => {
+    for (const alt of xApiAlternatives) {
+      assert.ok(alt.website.startsWith('http'), `${alt.name} website must start with http`)
+    }
+  })
+})