falconTS/__tests__/mnemonic.test.ts

import { uint8ArrayToMnemonic, mnemonicToUint8Array, validateMnemonic, generateMnemonic } from '../src/mnemonic';
import Falcon from '../src/falcon';

describe('Mnemonic Implementation', () => {
  describe('Basic Functionality', () => {
    it('should generate valid mnemonics', () => {
      const mnemonic = generateMnemonic();
      expect(validateMnemonic(mnemonic)).toBe(true);
      
      // Check mnemonic format
      const words = mnemonic.split(' ');
      expect(words.length).toBe(12);
    });

    it('should convert between Uint8Array and mnemonic', () => {
      const originalData = new Uint8Array([1, 2, 3, 4, 5]);
      const mnemonic = uint8ArrayToMnemonic(originalData);
      const recoveredData = mnemonicToUint8Array(mnemonic);
      
      // The recovered data should be 48 bytes (required for Falcon)
      expect(recoveredData.length).toBe(48);
    });

    it('should validate mnemonics correctly', () => {
      const validMnemonic = generateMnemonic();
      expect(validateMnemonic(validMnemonic)).toBe(true);
      
      const invalidMnemonic = 'not a valid mnemonic phrase';
      expect(validateMnemonic(invalidMnemonic)).toBe(false);
    });
  });

  describe('Falcon Integration', () => {
    let falcon: Falcon;
    let mnemonic: string;
    let seed: Uint8Array;

    beforeEach(async () => {
      // Generate a new mnemonic and initialize Falcon
      mnemonic = generateMnemonic();
      seed = mnemonicToUint8Array(mnemonic);
      
      falcon = new Falcon();
      await falcon.init();
    });

    it('should generate valid 48-byte seeds', () => {
      const seed = mnemonicToUint8Array(mnemonic);
      expect(seed.length).toBe(48);
    });

    it('should generate working key pairs from mnemonic', async () => {
      // Generate keys from seed
      await falcon.genkey(seed);
      const keypair = await falcon.getKeypair();
      
      expect(keypair.pk).toBeDefined();
      expect(keypair.sk).toBeDefined();
    });

    it('should recover working keys from mnemonic', async () => {
      // Generate original keys
      await falcon.genkey(seed);
      const originalKeypair = await falcon.getKeypair();
      
      // Create new instance and recover keys
      const recoveredFalcon = new Falcon();
      await recoveredFalcon.init();
      await recoveredFalcon.genkey(seed);
      const recoveredKeypair = await recoveredFalcon.getKeypair();
      
      // Compare keys
      expect(Buffer.from(recoveredKeypair.pk).toString('hex'))
        .toBe(Buffer.from(originalKeypair.pk).toString('hex'));
      expect(Buffer.from(recoveredKeypair.sk).toString('hex'))
        .toBe(Buffer.from(originalKeypair.sk).toString('hex'));
    });

    it('should sign and verify with recovered keys', async () => {
      // Generate original keys and sign a message
      await falcon.genkey(seed);
      const message = 'Test message';
      const signature = await falcon.sign(message);
      
      // Verify with original keys
      const originalVerification = await falcon.verify(message, signature);
      expect(originalVerification).toBe(true);
      
      // Recover keys in new instance
      const recoveredFalcon = new Falcon();
      await recoveredFalcon.init();
      await recoveredFalcon.genkey(seed);
      
      // Sign with recovered keys
      const newMessage = 'Another test message';
      const newSignature = await recoveredFalcon.sign(newMessage);
      
      // Verify with recovered keys
      const recoveredVerification = await recoveredFalcon.verify(newMessage, newSignature);
      expect(recoveredVerification).toBe(true);
      
      // Cross-verify: verify new signature with original instance
      const crossVerification = await falcon.verify(newMessage, newSignature);
      expect(crossVerification).toBe(true);
    });

    it('should handle invalid mnemonics', () => {
      const invalidMnemonics = [
        'invalid mnemonic',
        'too few words',
        'too many words in this mnemonic phrase which should fail',
        ''
      ];

      invalidMnemonics.forEach(mnemonic => {
        expect(validateMnemonic(mnemonic)).toBe(false);
        expect(() => mnemonicToUint8Array(mnemonic)).toThrow();
      });
    });
  });
});