Will It Vibe?fmt.Errorf uses %v instead of %w for an error
Part of Code Quality & Syntax, which counts for 20% of the overall score. When this check fires it deducts 4 points from that category, once per scan, no matter how many places it turns up.
What it detects
fmt.Errorf formats err with %v, which stringifies it, instead of %w, which wraps it so errors.Is and errors.As can still find it further up the call stack. Once %v is used the original error value is unrecoverable to callers.
Why it matters
fmt.Errorf with %v formats an error into a plain string: the returned error no longer has any structural relationship to the original one, so a caller further up the stack that uses errors.Is or errors.As to check for a specific underlying error (a sentinel like sql.ErrNoRows, or a typed error) will not find it, even though the message printed to a log looks the same. %w instead wraps the original error so it stays discoverable through the whole chain of callers.
How to fix it
Change the %v that formats the error argument to %w. This only changes how the error is wrapped internally; the printed message stays the same, but errors.Is/errors.As can now see through to the original error. Only use %w once per Errorf call, on the actual error being wrapped, not on unrelated string or numeric arguments.
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