gofix

Documentation

Overview

Package gofix defines an Analyzer that inlines calls to functions and uses of constants marked with a "//go:fix inline" doc comment.

Analyzer gofix

gofix: apply fixes based on go:fix comment directives

The gofix analyzer inlines functions and constants that are marked for inlining.

Functions

Given a function that is marked for inlining, like this one:

//go:fix inline
func Square(x int) int { return Pow(x, 2) }

this analyzer will recommend that calls to the function elsewhere, in the same or other packages, should be inlined.

Inlining can be used to move off of a deprecated function:

// Deprecated: prefer Pow(x, 2).
//go:fix inline
func Square(x int) int { return Pow(x, 2) }

It can also be used to move off of an obsolete package, as when the import path has changed or a higher major version is available:

package pkg

import pkg2 "pkg/v2"

//go:fix inline
func F() { pkg2.F(nil) }

Replacing a call pkg.F() by pkg2.F(nil) can have no effect on the program, so this mechanism provides a low-risk way to update large numbers of calls. We recommend, where possible, expressing the old API in terms of the new one to enable automatic migration.

Constants

Given a constant that is marked for inlining, like this one:

//go:fix inline
const Ptr = Pointer

this analyzer will recommend that uses of Ptr should be replaced with Pointer.

As with functions, inlining can be used to replace deprecated constants and constants in obsolete packages.

A constant definition can be marked for inlining only if it refers to another named constant.

The "//go:fix inline" comment must appear before a single const declaration on its own, as above; before a const declaration that is part of a group, as in this case:

const (
   C = 1
   //go:fix inline
   Ptr = Pointer
)

or before a group, applying to every constant in the group:

//go:fix inline
const (
	Ptr = Pointer
    Val = Value
)

The proposal https://go.dev/issue/32816 introduces the "//go:fix" directives.

You can use this (officially unsupported) command to apply gofix fixes en masse:

$ go run golang.org/x/tools/gopls/internal/analysis/gofix/cmd/gofix@latest -test ./...

Index

• Variables

Variables

var Analyzer = &analysis.Analyzer{
	Name:      "gofix",
	Doc:       analysisinternal.MustExtractDoc(doc, "gofix"),
	URL:       "https://pkg.go.dev/golang.org/x/tools/gopls/internal/analysis/gofix",
	Run:       run,
	FactTypes: []analysis.Fact{new(goFixInlineFuncFact), new(goFixInlineConstFact)},
	Requires:  []*analysis.Analyzer{inspect.Analyzer},
}