What canceled my Go context?

Automated excerpt

The caller of processOrder has no idea what actually happened. You’d think wrapping the error helps:if err := checkInventory(ctx, orderID); err ! = nil { return fmt. Errorf("checking inventory for %s: %w", orderID, err) context was canceled. Here’s the same processOrder rewritten to use it:func processOrder(ctx context. Context, orderID string) error { if err := checkInventory(ctx, orderID); err ! = nil { if err := chargePayment(ctx, orderID); err ! = nil { via %wNow you can read the cause with context. Cause(ctx). Err() will always return nil, Canceled, or DeadlineExceeded.

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