fix: configure Jest for ES modules in kraiken-lib (#88)

Updates Jest configuration to properly handle ES module syntax:
- Switch to ts-jest/presets/default-esm preset
- Add custom resolver to map .js imports to .ts source files
- Configure extensionsToTreatAsEsm for TypeScript files
- Enable useESM in ts-jest globals

This resolves module resolution errors when running tests in
kraiken-lib which uses "type": "module" in package.json.

Fixes #85

Co-authored-by: openhands <openhands@all-hands.dev>
Reviewed-on: https://codeberg.org/johba/harb/pulls/88

kraiken-lib/jest.config.cjs

@@ -1,5 +1,13 @@
 module.exports = {
-  preset: 'ts-jest',
+  preset: 'ts-jest/presets/default-esm',
   testEnvironment: 'node',
-  maxWorkers: 1
+  maxWorkers: 1,
+  extensionsToTreatAsEsm: ['.ts'],
+  resolver: './jest.resolver.cjs',
+  globals: {
+    'ts-jest': {
+      useESM: true,
+      tsconfig: './tsconfig.json'
+    }
+  }
 };

kraiken-lib/jest.resolver.cjs

@@ -0,0 +1,16 @@
+module.exports = (request, options) => {
+  try {
+    return options.defaultResolver(request, options);
+  } catch (originalError) {
+    if (!request.endsWith('.js')) {
+      throw originalError;
+    }
+
+    const tsRequest = request.replace(/\.js$/, '.ts');
+    try {
+      return options.defaultResolver(tsRequest, options);
+    } catch (fallbackError) {
+      throw originalError;
+    }
+  }
+};

kraiken-lib/src/tests/functions.test.ts

@@ -1,27 +1,18 @@
 import { describe, expect, test } from '@jest/globals';
 import { bytesToUint256LittleEndian, uint256ToBytesLittleEndian } from '../subgraph';
-import { Position, PositionStatus } from '../__generated__/graphql';
 
 describe('BigInt Conversion Functions', () => {
   test('converts uint256 to bytes and back (little endian)', async () => {
-    const mockPos: Position = {
-      __typename: 'Position',
-      id: uint256ToBytesLittleEndian(3n),
-      owner: '0x8db6b632d743aef641146dc943acb64957155388',
-      share: '0.000001',
-      creationTime: 1610000000,
-      taxRate: '0.01',
-      status: PositionStatus.Active, // Enum usage
-    };
+    const mockId = uint256ToBytesLittleEndian(3n);
     let hexString = '0x';
 
-    for (let i = 0; i < mockPos.id.length; i++) {
+    for (let i = 0; i < mockId.length; i++) {
       // Convert each byte to a hexadecimal string and pad with zero if needed
-      hexString += mockPos.id[i].toString(16).padStart(2, '0');
+      hexString += mockId[i].toString(16).padStart(2, '0');
     }
     expect(hexString).toEqual('0x03000000');
 
     // return hexString;
-    expect(bytesToUint256LittleEndian(mockPos.id)).toEqual(3n);
+    expect(bytesToUint256LittleEndian(mockId)).toEqual(3n);
   });
 });

kraiken-lib/src/tests/snatch.test.ts

@@ -1,8 +1,6 @@
 import { describe, expect, test } from '@jest/globals';
 import { getSnatchList, minimumTaxRate, selectSnatchPositions, type SnatchablePosition } from '../snatch';
-import { uint256ToBytesLittleEndian } from '../subgraph';
-import type { Position } from '../__generated__/graphql';
-import { PositionStatus } from '../__generated__/graphql';
+import type { Positions } from '../__generated__/graphql';
 
 describe('snatch', () => {
   test('minimumTaxRate finds the lowest tax', () => {
@@ -46,26 +44,40 @@ describe('snatch', () => {
   test('getSnatchList converts subgraph positions', () => {
     const stakeTotalSupply = 1_000_000n * 10n ** 18n;
 
-    const positions: Position[] = [
+    const positions: Positions[] = [
       {
-        __typename: 'Position',
-        id: uint256ToBytesLittleEndian(1n),
+        __typename: 'positions',
+        id: '0x01',
         owner: '0xowner1',
         share: 0.0001,
-        creationTime: 0,
-        lastTaxTime: 0,
+        creationTime: '0',
+        lastTaxTime: '0',
         taxRate: 0.02,
-        status: PositionStatus.Active,
+        status: 'Active',
+        createdAt: '0',
+        kraikenDeposit: '0',
+        payout: '0',
+        snatched: 0,
+        stakeDeposit: '0',
+        taxPaid: '0',
+        totalSupplyInit: '0',
       },
       {
-        __typename: 'Position',
-        id: uint256ToBytesLittleEndian(2n),
+        __typename: 'positions',
+        id: '0x02',
         owner: '0xowner2',
         share: 0.0002,
-        creationTime: 0,
-        lastTaxTime: 0,
+        creationTime: '0',
+        lastTaxTime: '0',
         taxRate: 0.01,
-        status: PositionStatus.Active,
+        status: 'Active',
+        createdAt: '0',
+        kraikenDeposit: '0',
+        payout: '0',
+        snatched: 0,
+        stakeDeposit: '0',
+        taxPaid: '0',
+        totalSupplyInit: '0',
       },
     ];