# Mixed Async Styles
# Detects mixing async/await with promise chains in the same function
id: mixed-async-styles
name: Mixed Async/Await and Promise Chains
severity: warning
category: style
defect_class: async-misuse
inline_tier: warning
language: typescript

message: "Mixed async/await + promise chains — use consistent async style"

description: |
  Mixing async/await with .then()/.catch() chains in the same function
  is confusing and inconsistent. Choose one style per function.
  
  ✅ FIXES:
  1. Convert all to async/await (preferred)
  2. Convert all to promise chains (if needed for specific control flow)

query: |
  (function_declaration
    (async_modifier)
    body: (statement_block) @BODY)

# Post-filter: Check if body contains both await and .then()
post_filter: has_mixed_async

metavars:
  - BODY

tags:
  - style
  - async
  - consistency

examples:
  bad: |
    async function getUser() {
      const response = await fetch('/api/user');
      return response.json().then(data => data.name); // Mixed!
    }
  
  good: |
    async function getUser() {
      const response = await fetch('/api/user');
      const data = await response.json(); // Consistent async/await
      return data.name;
    }

has_fix: false