34 lines
1.6 KiB
Plaintext
34 lines
1.6 KiB
Plaintext
Vet is a tool that checks correctness of Go programs. It runs a suite of tests,
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each tailored to check for a particular class of errors. Examples include incorrect
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Printf format verbs and malformed build tags.
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Over time many checks have been added to vet's suite, but many more have been
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rejected as not appropriate for the tool. The criteria applied when selecting which
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checks to add are:
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Correctness:
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Vet's checks are about correctness, not style. A vet check must identify real or
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potential bugs that could cause incorrect compilation or execution. A check that
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only identifies stylistic points or alternative correct approaches to a situation
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is not acceptable.
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Frequency:
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Vet is run every day by many programmers, often as part of every compilation or
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submission. The cost in execution time is considerable, especially in aggregate,
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so checks must be likely enough to find real problems that they are worth the
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overhead of the added check. A new check that finds only a handful of problems
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across all existing programs, even if the problem is significant, is not worth
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adding to the suite everyone runs daily.
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Precision:
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Most of vet's checks are heuristic and can generate both false positives (flagging
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correct programs) and false negatives (not flagging incorrect ones). The rate of
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both these failures must be very small. A check that is too noisy will be ignored
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by the programmer overwhelmed by the output; a check that misses too many of the
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cases it's looking for will give a false sense of security. Neither is acceptable.
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A vet check must be accurate enough that everything it reports is worth examining,
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and complete enough to encourage real confidence.
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