Severity: warning
Category: lint
Stage: Stage 3

Description

A Promise-typed expression is used as a standalone statement without being awaited, returned, assigned, or otherwise consumed. Fire-and-forget async work hides failures and races shutdown.

This rule is type-aware: the linter checks the synthesized type at each expression statement.

Example

// ✗ lint warning
export async function run(): Promise<void> {
  fetchData()   // SJS-L015 — Promise ignored
}

Fix

Await, return, or explicitly handle the promise:

// ✓ correct
export async function run(): Promise<void> {
  await fetchData()
}

// ✓ correct — intentional fire-and-forget with handler
void fetchData().catch((e) => console.error(e))

Configuration

{
  "lint": {
    "L015": "error" | "warn" | "off"
  }
}

Default: "warn" in standard mode, "error" in --strict mode.

Related codes

• SJS-L016 — unhandled Result
• SJS-L017 — prefer Result over throw