Awesome
dogsled 
dogsled is a Go static analysis tool to find assignments/declarations with too many blank identifiers (e.g. x, _, _, _ := f()). Its name was inspired from this reddit post.
Installation
go get -u github.com/alexkohler/dogsled/cmd/dogsled
Usage
Similar to other Go static analysis tools (such as golint, go vet), dogsled can be invoked with one or more filenames, directories, or packages named by its import path. dogsled also supports the ... wildcard. By default, it will search for assignment with more than two blank identifiers.
dogsled [flags] files/directories/packages
Flags
- -tests (default true) - Include test files in analysis
- -n (default 2) - Maximum number of blank identifiers allowed in an assignment statement
- -set_exit_status (default false) - Set exit status to 1 if any issues are found
Example
Some examples from the Go standard library
$ dogsled go/src/...
go/src/crypto/elliptic/elliptic_test.go:553: declaration has 3 blank identifiers: priv, _, _, _ := GenerateKey(p256,go/src/image/names.go:46: declaration has 3 blank identifiers: _, _, _, a := c.C.RGBA()
go/src/image/color/color.go:232: declaration has 3 blank identifiers: _, _, _, a := c.RGBA()
go/src/image/color/color.go:240: declaration has 3 blank identifiers: _, _, _, a := c.RGBA()
go/src/internal/cpu/cpu_x86.go:67: declaration has 3 blank identifiers: maxID, _, _, _ := cpuid(0, 0)
go/src/internal/cpu/cpu_x86.go:100: declaration has 3 blank identifiers: _, ebx7, _, _ := cpuid(7, 0)
go/src/math/big/natconv_test.go:286: declaration has 3 blank identifiers: x, _, _, _ = x.scan(strings.NewReader(pi),go/src/reflect/value.go:172: declaration has 3 blank identifiers: pc, _, _, _ := runtime.Caller(2)
go/src/reflect/makefunc.go:62: declaration has 4 blank identifiers: _, _, _, stack, _ := funcLayout(t, nil)
go/src/reflect/makefunc.go:113: declaration has 4 blank identifiers: _, _, _, stack, _ := funcLayout(funcType, nil)
go/src/runtime/softfloat64.go:309: declaration has 4 blank identifiers: _, _, _, _ = fi, fn, gi, gn
go/src/runtime/symtab_test.go:54: declaration has 3 blank identifiers: _, _, line, _ := runtime.Caller(1)
go/src/syscall/syscall_unix_test.go:182: declaration has 3 blank identifiers: _, oobn, _, _, err := uc.ReadMsgUnixgo/src/time/time.go:498: declaration has 3 blank identifiers: year, _, _, _ := t.date(false)
go/src/time/time.go:504: declaration has 3 blank identifiers: _, month, _, _ := t.date(true)
go/src/time/time.go:510: declaration has 3 blank identifiers: _, _, day, _ := t.date(true)
go/src/time/time.go:624: declaration has 3 blank identifiers: _, _, _, yday := t.date(false)
Contributing
Please open an issue and/or a PR for any features/bugs.
Other static analysis tools
If you've enjoyed dogsled, take a look at my other static anaylsis tools!