go/src/cmd/go/internal/imports/build.go

var bSlashSlash …

var bStarSlash …

var bSlashStar …

var bPlusBuild …

var goBuildComment …

var errMultipleGoBuild …

func isGoBuildComment(line []byte) bool { … }

// ShouldBuild reports whether it is okay to use this file,
// The rule is that in the file's leading run of // comments
// and blank lines, which must be followed by a blank line
// (to avoid including a Go package clause doc comment),
// lines beginning with '// +build' are taken as build directives.
//
// The file is accepted only if each such line lists something
// matching the file. For example:
//
//	// +build windows linux
//
// marks the file as applicable only on Windows and Linux.
//
// If tags["*"] is true, then ShouldBuild will consider every
// build tag except "ignore" to be both true and false for
// the purpose of satisfying build tags, in order to estimate
// (conservatively) whether a file could ever possibly be used
// in any build.
func ShouldBuild(content []byte, tags map[string]bool) bool { … }

func parseFileHeader(content []byte) (trimmed, goBuild []byte, sawBinaryOnly bool, err error) { … }

// matchTag reports whether the tag name is valid and tags[name] is true.
// As a special case, if tags["*"] is true and name is not empty or ignore,
// then matchTag will return prefer instead of the actual answer,
// which allows the caller to pretend in that case that most tags are
// both true and false.
func matchTag(name string, tags map[string]bool, prefer bool) bool { … }

// eval is like
//
//	x.Eval(func(tag string) bool { return matchTag(tag, tags) })
//
// except that it implements the special case for tags["*"] meaning
// all tags are both true and false at the same time.
func eval(x constraint.Expr, tags map[string]bool, prefer bool) bool { … }

// Eval is like
//
//	x.Eval(func(tag string) bool { return matchTag(tag, tags) })
//
// except that it implements the special case for tags["*"] meaning
// all tags are both true and false at the same time.
func Eval(x constraint.Expr, tags map[string]bool, prefer bool) bool { … }

// MatchFile returns false if the name contains a $GOOS or $GOARCH
// suffix which does not match the current system.
// The recognized name formats are:
//
//	name_$(GOOS).*
//	name_$(GOARCH).*
//	name_$(GOOS)_$(GOARCH).*
//	name_$(GOOS)_test.*
//	name_$(GOARCH)_test.*
//	name_$(GOOS)_$(GOARCH)_test.*
//
// Exceptions:
//
//	if GOOS=android, then files with GOOS=linux are also matched.
//	if GOOS=illumos, then files with GOOS=solaris are also matched.
//	if GOOS=ios, then files with GOOS=darwin are also matched.
//
// If tags["*"] is true, then MatchFile will consider all possible
// GOOS and GOARCH to be available and will consequently
// always return true.
func MatchFile(name string, tags map[string]bool) bool { … }