Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string. Vet uses heuristics that do not guarantee all reports are genuine problems, but it can find errors not caught by the compilers.
Vet is normally invoked through the go command. This command vets the package in the current directory:
whereas this one vets the packages whose path is provided:
go vet my/project/...
Use "go help packages" to see other ways of specifying which packages to vet.
Vet's exit code is non-zero for erroneous invocation of the tool or if a problem was reported, and 0 otherwise. Note that the tool does not check every possible problem and depends on unreliable heuristics, so it should be used as guidance only, not as a firm indicator of program correctness.
To list the available checks, run "go tool vet help":
asmdecl report mismatches between assembly files and Go declarations assign check for useless assignments atomic check for common mistakes using the sync/atomic package bools check for common mistakes involving boolean operators buildtag check that +build tags are well-formed and correctly located cgocall detect some violations of the cgo pointer passing rules composites check for unkeyed composite literals copylocks check for locks erroneously passed by value httpresponse check for mistakes using HTTP responses loopclosure check references to loop variables from within nested functions lostcancel check cancel func returned by context.WithCancel is called nilfunc check for useless comparisons between functions and nil printf check consistency of Printf format strings and arguments shift check for shifts that equal or exceed the width of the integer stdmethods check signature of methods of well-known interfaces structtag check that struct field tags conform to reflect.StructTag.Get tests check for common mistaken usages of tests and examples unmarshal report passing non-pointer or non-interface values to unmarshal unreachable check for unreachable code unsafeptr check for invalid conversions of uintptr to unsafe.Pointer unusedresult check for unused results of calls to some functions
For details and flags of a particular check, such as printf, run "go tool vet help printf".
By default, all checks are performed. If any flags are explicitly set to true, only those tests are run. Conversely, if any flag is explicitly set to false, only those tests are disabled. Thus -printf=true runs the printf check, and -printf=false runs all checks except the printf check.
For information on writing a new check, see golang.org/x/tools/go/analysis.
-c=N display offending line plus N lines of surrounding context -json emit analysis diagnostics (and errors) in JSON format