Cursor rule

1---
2description: TypeScript/JavaScript File Rules
3globs: ["**/*.ts", "**/*.tsx", "**/*.js", "**/*.jsx"]
4alwaysApply: false
5---
6 
7 
8# TypeScript/JavaScript File Rules
9 
10## Overview
11 
12Rules for modifying TypeScript (`*.ts`, `*.tsx`) and JavaScript (`*.js`, `*.jsx`) files in go-crypto-wallet.
13 
14## Applicable Directories
15 
16| App              | Language              | Runtime | Path                     | Status                     |
17| ---------------- | --------------------- | ------- | ------------------------ | -------------------------- |
18| xrpl-grpc-server | TypeScript            | **Bun** | `apps/xrpl-grpc-server/` | **READ-ONLY** (deprecated) |
19| eth-contracts    | JavaScript/TypeScript | Node.js | `apps/eth-contracts/`      | Active                     |
20 
21## Verification Commands
22 
23**Navigate to app directory first:**
24 
25### xrpl-grpc-server (TypeScript + Bun) - Active Development
26 
27```bash
28cd apps/xrpl-grpc-server
29bun install           # Install dependencies (if needed)
30bun run lint          # Lint with Biome
31bun run format        # Format with Biome
32bun run typecheck     # TypeScript type checking
33bun run dev           # Run dev server with hot reload
34bun run build         # Build for production
35bun run proto         # Generate protobuf code
36```
37 
38> **Important**: See @.claude/rules/apps/bun.md for Bun runtime rules.
39> **DO NOT** use `npm`/`npx` commands - always use `bun`/`bunx` instead.
40 
41### eth-contracts (JavaScript/Solidity)
42 
43```bash
44cd apps/eth-contracts
45npm install           # Install dependencies (if needed)
46npm run lint          # Lint Solidity files
47npm run lint-js       # Lint JavaScript/TypeScript files
48npm run fmt           # Format all files with Prettier
49npm run build         # Compile contracts with Truffle
50npm run test-all      # Run all tests
51```
52 
53## Command Summary
54 
55| App              | Lint              | Format           | Build           | Test                |
56| ---------------- | ----------------- | ---------------- | --------------- | ------------------- |
57| xrpl-grpc-server | `bun run lint`    | `bun run format` | `bun run build` | `bun run typecheck` |
58| eth-contracts    | `npm run lint-js` | `npm run fmt`    | `npm run build` | `npm run test-all`  |
59 
60## Code Style
61 
62### TypeScript Best Practices
63 
64```typescript
65// Good: Explicit types
66function getBalance(address: string): Promise<number> {
67  // ...
68}
69 
70// Good: Async/await with error handling
71async function fetchData(): Promise<Data> {
72  try {
73    const result = await api.call();
74    return result;
75  } catch (error) {
76    throw new Error(`Failed to fetch data: ${error.message}`);
77  }
78}
79 
80// Avoid: any type (unless absolutely necessary)
81// Bad: function process(data: any)
82// Good: function process(data: TransactionData)
83```
84 
85### Critical Value Handling
86 
87Never use nullish coalescing (`??`) with empty string for critical values like secrets or keys.
88Instead, throw an error to fail fast and prevent silent failures.
89 
90```typescript
91// Bad: Silently returns empty string if seed is undefined
92const secret = wallet.seed ?? "";
93 
94// Good: Fail fast with explicit error
95if (!wallet.seed) {
96  throw new Error("Failed to generate a wallet seed.");
97}
98const secret = wallet.seed;
99```
100 
101### Module Exports
102 
103Prefer named exports over default exports for consistency and better tooling support.
104 
105```typescript
106// Bad: Mixed exports cause inconsistent import styles
107export const myService = { ... };
108export default myService;
109 
110// Good: Named exports only
111export const myService = { ... };
112```
113 
114### Import Order
115 
1161. Node.js built-ins
1172. External packages
1183. Internal modules
119 
120#### xrpl-grpc-server (xrpl.js 4.5.0)
121 
122```typescript
123import * as path from "path";
124 
125import { Client, Wallet, xrpToDrops, dropsToXrp } from "xrpl";
126import { createConnectRouter } from "@connectrpc/connect";
127 
128import { AccountService } from "./services/account";
129```
130 
131#### eth-contracts
132 
133```typescript
134import * as path from "path";
135 
136import { ethers } from "ethers";
137 
138import { TokenService } from "./services/token";
139```
140 
141## Auto-Generated Files
142 
143**DO NOT EDIT:**
144 
145| App              | Generated Files                                                  |
146| ---------------- | ---------------------------------------------------------------- |
147| xrpl-grpc-server | `apps/xrpl-grpc-server/src/protogen/` (Buf/ConnectRPC generated) |
148| eth-contracts    | `apps/eth-contracts/build/` (Truffle build artifacts)              |
149 
150## Security
151 
152- No hardcoded secrets or API keys
153- No sensitive data in logs
154- Input validation at boundaries
155- Use environment variables for configuration
156 
157## Quick Checklist
158 
159### xrpl-grpc-server (Active)
160 
161- [ ] `bun run lint` passes
162- [ ] `bun run format` applied
163- [ ] `bun run typecheck` passes
164- [ ] `bun run build` passes
165- [ ] No `any` types (unless documented reason)
166- [ ] Async errors properly handled
167 
168### eth-contracts
169 
170- [ ] `npm run lint-js` passes
171- [ ] `npm run fmt` applied
172- [ ] `npm run build` passes
173- [ ] `npm run test-all` passes
174 
175## Related Documentation
176 
177- @apps/xrpl-grpc-server/README.md - xrpl-grpc-server documentation
178- @apps/xrpl-grpc-server/docs/MIGRATION-GUIDE.md - Migration guide from ripple-lib
179- @apps/xrpl-grpc-server/package.json - xrpl-grpc-server scripts
180- @apps/eth-contracts/package.json - eth-contracts scripts
181 
182## Related Skills
183 
184- `typescript-development` - Full TypeScript workflow
185- `solidity-development` - For Solidity contracts in eth-contracts
186 
187## Related Rules
188 
189- @.claude/rules/apps/bun.md - Bun runtime rules (use bun/bunx instead of npm/npx)
190- @.claude/rules/apps/xrp-server.md - XRP server directory rules
191