shepherdwind · shepherdwind · Apr 5, 2026 · Apr 5, 2026
diff --git a/docs/tasks/plan.md b/docs/tasks/plan.md
@@ -30,8 +30,8 @@ Raise test coverage from 46.92% to 90%+ across the entire repository by adding u
 
 | # | Task | Status | Depends On | File |
 |---|------|--------|------------|------|
-| 7 | Domain & application layer test coverage | reviewed | — | [007](007-domain-app-test-coverage.md) |
-| 8 | Infrastructure utilities & events test coverage | pending | — | [008](008-infra-utils-events-test-coverage.md) |
+| 7 | Domain & application layer test coverage | done (PR #9) | — | [007](007-domain-app-test-coverage.md) |
+| 8 | Infrastructure utilities & events test coverage | reviewed | — | [008](008-infra-utils-events-test-coverage.md) |
 | 9 | Infrastructure adapters test coverage | pending | — | [009](009-infra-adapters-test-coverage.md) |
 
 ### Dependency Graph

diff --git a/src/infrastructure/beancount/__tests__/beancount-query.service.test.ts b/src/infrastructure/beancount/__tests__/beancount-query.service.test.ts
@@ -1,4 +1,16 @@
 import { BeancountQueryService } from '../beancount-query.service';
+import * as child_process from 'child_process';
+import * as util from 'util';
+
+// Mock child_process.exec for executeQuery tests
+jest.mock('child_process');
+jest.mock('util', () => {
+  const original = jest.requireActual('util');
+  return {
+    ...original,
+    promisify: jest.fn((fn: unknown) => fn),
+  };
+});
 
 class TestBeancountQueryService extends BeancountQueryService {
   public processQueryResult(rawResult: string) {
@@ -97,4 +109,38 @@ Assets:DBS:SGD:Wife            -102.32 SGD
       });
     });
   });
-}); 
+
+  describe('queryByDateRange', () => {
+    it('should execute query and process result', async () => {
+      const mockExec = child_process.exec as unknown as jest.Mock;
+      mockExec.mockResolvedValue({
+        stdout: `
+           account                  ps
+-----------------------------  -----------
+Assets:DBS:SGD:Saving            -50.00 SGD
+Expenses:Food                     50.00 SGD
+`,
+      });
+
+      const startDate = new Date('2024-03-01');
+      const endDate = new Date('2024-03-31');
+      const result = await service.queryByDateRange(startDate, endDate);
+
+      expect(result.assets).toHaveLength(1);
+      expect(result.expenses).toHaveLength(1);
+      expect(result.assets[0].amount).toBe(-50);
+    });
+
+    it('should throw when command execution fails', async () => {
+      const mockExec = child_process.exec as unknown as jest.Mock;
+      mockExec.mockRejectedValue(new Error('command not found'));
+
+      const startDate = new Date('2024-03-01');
+      const endDate = new Date('2024-03-31');
+
+      await expect(service.queryByDateRange(startDate, endDate)).rejects.toThrow(
+        'Failed to execute Beancount query'
+      );
+    });
+  });
+});
diff --git a/src/infrastructure/email-parsers/__tests__/dbs-transaction-extractor.test.ts b/src/infrastructure/email-parsers/__tests__/dbs-transaction-extractor.test.ts
@@ -0,0 +1,134 @@
+jest.mock('../../utils/logger', () => ({
+  logger: {
+    info: jest.fn(),
+    error: jest.fn(),
+    warn: jest.fn(),
+    debug: jest.fn(),
+  },
+}));
+
+import { extractTransactionData } from '../dbs-transaction-extractor';
+import { Email } from '../../gmail/gmail.adapter';
+import { Currency } from '../../../domain/models/types';
+
+function createEmail(body: string): Email {
+  return {
+    id: 'test-1',
+    subject: 'Card Transaction Alert',
+    from: 'alert@dbs.com',
+    to: 'test@iling.fun',
+    body,
+  };
+}
+
+const STANDARD_BODY = `Card Transaction Alert
+Transaction Ref: 510805332088
+Dear Sir / Madam,
+Date & Time: 18 Apr 13:29 (SGT)
+Amount: SGD50.00
+From: DBS/POSB card ending 8558
+To: GRAB FOOD
+
+Please do not reply to this email`;
+
+describe('extractTransactionData', () => {
+  it('should extract all fields from standard DBS email', () => {
+    const result = extractTransactionData(createEmail(STANDARD_BODY));
+
+    expect(result).not.toBeNull();
+    expect(result!.amount).toBe(50);
+    expect(result!.currency).toBe(Currency.SGD);
+    expect(result!.merchant).toBe('GRAB FOOD');
+    expect(result!.cardInfo).toContain('8558');
+    expect(result!.date).toBeInstanceOf(Date);
+    expect(result!.date.getMonth()).toBe(3); // April = 3
+    expect(result!.date.getDate()).toBe(18);
+  });
+
+  it('should handle S$ amount format', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: S$123.45
+From: DBS card ending 1234
+To: STORE`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).not.toBeNull();
+    expect(result!.amount).toBe(123.45);
+    expect(result!.currency).toBe(Currency.SGD);
+  });
+
+  it('should handle USD amount format', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: USD29.99
+From: DBS card ending 1234
+To: AMAZON`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).not.toBeNull();
+    expect(result!.amount).toBe(29.99);
+    expect(result!.currency).toBe('USD');
+  });
+
+  it('should return null when amount is missing', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+From: DBS card ending 1234
+To: GRAB FOOD`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).toBeNull();
+  });
+
+  it('should return null when date is missing', () => {
+    const body = `Amount: SGD50.00
+From: DBS card ending 1234
+To: GRAB FOOD`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).toBeNull();
+  });
+
+  it('should return null when merchant is missing', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: SGD50.00
+From: DBS card ending 1234`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).toBeNull();
+  });
+
+  it('should return empty card info when From: is not found', () => {
+    // Craft a body where Amount can be found but no From:/To: after it in normal position
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: SGD50.00
+From:
+To: GRAB FOOD`;
+
+    const result = extractTransactionData(createEmail(body));
+    // The extraction depends on format, cardInfo may be empty
+    if (result) {
+      expect(typeof result.cardInfo).toBe('string');
+    }
+  });
+
+  it('should handle amount with no decimal', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: SGD100
+From: DBS card ending 1234
+To: STORE`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).not.toBeNull();
+    expect(result!.amount).toBe(100);
+  });
+
+  it('should round floating point amounts to 2 decimals', () => {
+    const body = `Date & Time: 18 Apr 13:29 (SGT)
+Amount: SGD10.105
+From: DBS card ending 1234
+To: STORE`;
+
+    const result = extractTransactionData(createEmail(body));
+    expect(result).not.toBeNull();
+    expect(result!.amount).toBe(10.11); // Rounded
+  });
+});
diff --git a/src/infrastructure/email-parsers/__tests__/email-parser-factory.test.ts b/src/infrastructure/email-parsers/__tests__/email-parser-factory.test.ts
@@ -0,0 +1,118 @@
+jest.mock('../../utils/logger', () => ({
+  logger: {
+    info: jest.fn(),
+    error: jest.fn(),
+    warn: jest.fn(),
+    debug: jest.fn(),
+  },
+}));
+
+// Mock merchant-category-mapping to avoid file I/O
+jest.mock('../../../domain/models/merchant-category-mapping', () => ({
+  get merchantCategoryMappings() { return {}; },
+  findCategoryForMerchant: jest.fn(),
+  addMerchantToMapping: jest.fn(),
+  updateMerchantCategoryMappingsIfNeeded: jest.fn(),
+}));
+
+import { EmailParserFactory } from '../email-parser-factory';
+import { EmailParser } from '../email-parser.interface';
+import { Email } from '../../gmail/gmail.adapter';
+import { Transaction } from '../../../domain/models/transaction';
+
+describe('EmailParserFactory', () => {
+  let factory: EmailParserFactory;
+
+  beforeEach(() => {
+    factory = new EmailParserFactory();
+  });
+
+  describe('findParser', () => {
+    it('should find DBS parser for DBS emails', () => {
+      const email: Email = {
+        id: '1',
+        subject: 'Card Transaction Alert',
+        from: 'ibanking.alert@dbs.com',
+        to: 'test@test.com',
+        body: 'test',
+      };
+
+      const parser = factory.findParser(email);
+      expect(parser).not.toBeNull();
+    });
+
+    it('should return null for unknown email source', () => {
+      const email: Email = {
+        id: '1',
+        subject: 'Random Email',
+        from: 'noreply@unknown.com',
+        to: 'test@test.com',
+        body: 'test',
+      };
+
+      expect(factory.findParser(email)).toBeNull();
+    });
+  });
+
+  describe('registerParser', () => {
+    it('should register and use custom parser', () => {
+      const mockParser: EmailParser = {
+        canParse: (email: Email) => email.from.includes('custom.com'),
+        parse: jest.fn().mockResolvedValue(null),
+      };
+
+      factory.registerParser(mockParser);
+
+      const email: Email = {
+        id: '1',
+        subject: 'Custom',
+        from: 'noreply@custom.com',
+        to: 'test@test.com',
+        body: 'test',
+      };
+
+      expect(factory.findParser(email)).toBe(mockParser);
+    });
+  });
+
+  describe('parseEmail', () => {
+    it('should delegate to found parser', async () => {
+      const mockTransaction = {
+        date: new Date(),
+        description: 'test',
+        entries: [],
+      } as Transaction;
+
+      const mockParser: EmailParser = {
+        canParse: () => true,
+        parse: jest.fn().mockResolvedValue(mockTransaction),
+      };
+
+      factory.registerParser(mockParser);
+
+      const email: Email = {
+        id: '1',
+        subject: 'Test',
+        from: 'test@test.com',
+        to: 'test@test.com',
+        body: 'test',
+      };
+
+      const result = await factory.parseEmail(email);
+      expect(result).toBe(mockTransaction);
+    });
+
+    it('should return null when no parser matches', async () => {
+      const email: Email = {
+        id: '1',
+        subject: 'Random',
+        from: 'unknown@unknown.com',
+        to: 'test@test.com',
+        body: 'test',
+      };
+
+      const result = await factory.parseEmail(email);
+      expect(result).toBeNull();
+    });
+  });
+});