package shadow

import "golang.org/x/tools/go/analysis/passes/shadow"

Package shadow defines an Analyzer that checks for shadowed variables.

Analyzer shadow

shadow: check for possible unintended shadowing of variables

This analyzer check for shadowed variables. A shadowed variable is a variable declared in an inner scope with the same name and type as a variable in an outer scope, and where the outer variable is mentioned after the inner one is declared.

(This definition can be refined; the module generates too many false positives and is not yet enabled by default.)

For example:

func BadRead(f *os.File, buf []byte) error {
	var err error
	for {
		n, err := f.Read(buf) // shadows the function variable 'err'
		if err != nil {
			break // causes return of wrong value
		}
		foo(buf)
	}
	return err
}

Index

Variables

var Analyzer = &analysis.Analyzer{
	Name:     "shadow",
	Doc:      analysisutil.MustExtractDoc(doc, "shadow"),
	URL:      "https://pkg.go.dev/golang.org/x/tools/go/analysis/passes/shadow",
	Requires: []*analysis.Analyzer{inspect.Analyzer},
	Run:      run,
}

Source Files

doc.go shadow.go

Directories

PathSynopsis
go/analysis/passes/shadow/cmd
go/analysis/passes/shadow/cmd/shadowThe shadow command runs the shadow analyzer.
Version
v0.30.0 (latest)
Published
Feb 10, 2025
Platform
linux/amd64
Imports
8 packages
Last checked
3 hours ago

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