internal/frontend/symbol.go - pkgsite - Git at Google

 // Copyright 2021 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 package frontend

 import (
 	"fmt"
 	"sort"
 	"strings"

 	"golang.org/x/pkgsite/internal"
 )

 // Symbol is an element in the package API. A symbol can be a constant,
 // variable, function, type, field or method.
 type Symbol struct {
 	// Name is name of the symbol. At a given package version, name must be
 	// unique.
 	Name string

 	// Synopsis is the one line description of the symbol that is displayed.
 	Synopsis string

 	// Link is the link to the symbol name on pkg.go.dev.
 	Link string

 	// Section is the section that a symbol appears in.
 	Section internal.SymbolSection

 	// Kind is the type of a symbol, which is either a constant, variable,
 	// function, type, field or method.
 	Kind internal.SymbolKind

 	// Children contain the child symbols for this symbol. This will
 	// only be populated when the SymbolType is "Type". For example, the
 	// children of net/http.Handler are FileServer, NotFoundHandler,
 	// RedirectHandler, StripPrefix, and TimeoutHandler. Each child
 	// symbol will have ParentName set to the Name of this type.
 	Children []*Symbol

 	// Builds lists all of the build contexts supported by the symbol, it is
 	// only available for limited set of builds. If the symbol supports all
 	// build contexts, Builds will be nil.
 	Builds []string

 	// New indicates that the symbol is new as of the version where it is
 	// present. For example, if type Client was introduced in v1.0.0 and
 	// Client.Timeout was introduced in v1.1.0, New will be false for Client
 	// and true for Client.Timeout if this Symbol corresponds to v1.1.0.
 	New bool
 }

 // symbolsForVersions returns an array of symbols for use in the VersionSummary
 // of the specified version.
 func symbolsForVersion(pkgURLPath string, symbolsAtVersion map[string]*internal.UnitSymbol) [][]*Symbol {
 	nameToSymbol := map[string]*Symbol{}
 	for _, us := range symbolsAtVersion {
 		builds := symbolBuilds(us)
 		s, ok := nameToSymbol[us.Name]
 		if !ok {
 			s = &Symbol{
 				Name:     us.Name,
 				Synopsis: us.Synopsis,
 				Link:     symbolLink(pkgURLPath, us.Name, us.BuildContexts()),
 				Section:  us.Section,
 				Kind:     us.Kind,
 				New:      true,
 				Builds:   builds,
 			}
 		} else if !s.New && us.Kind == internal.SymbolKindType {
 			// It's possible that a symbol was already created if this is a parent
 			// symbol and we called addSymbol on the child symbol first. In that
 			// case, a parent symbol would have been created where s.New is set to
 			// false and s.Synopsis is set to the one created in createParent.
 			// Update those fields instead of overwritting the struct, since the
 			// struct's Children field would have already been populated.
 			s.New = true
 			s.Synopsis = us.Synopsis
 		}
 		if us.ParentName == us.Name {
 			// s is not a child symbol of a type, so add it to the map and
 			// continue.
 			nameToSymbol[us.Name] = s
 			continue
 		}

 		// s is a child symbol of a parent type, so append it to the Children field
 		// of the parent type.
 		parent, ok := nameToSymbol[us.ParentName]
 		if !ok {
 			parent = createParent(us, pkgURLPath)
 			nameToSymbol[us.ParentName] = parent
 		}
 		if len(parent.Builds) == len(s.Builds) {
 			s.Builds = nil
 		}
 		parent.Children = append(parent.Children, s)
 	}
 	return sortSymbols(nameToSymbol)
 }

 func symbolLink(pkgURLPath, name string, builds []internal.BuildContext) string {
 	if len(builds) == len(internal.BuildContexts) {
 		return fmt.Sprintf("%s#%s", pkgURLPath, name)
 	}

 	// When a symbol is introduced for a specific GOOS/GOARCH at a version,
 	// linking to an unspecified GOOS/GOARCH page might not take the user to
 	// the symbol. Instead, link to one of the supported build contexts.
 	return fmt.Sprintf("%s?GOOS=%s#%s", pkgURLPath, builds[0].GOOS, name)
 }

 func symbolBuilds(us *internal.UnitSymbol) []string {
 	if us.InAll() {
 		return nil
 	}
 	var builds []string
 	for _, b := range us.BuildContexts() {
 		builds = append(builds, b.String())
 	}
 	sort.Strings(builds)
 	return builds
 }

 // createParent creates a parent symbol for the provided unit symbol. This is
 // used when us is a child of a symbol that may have been introduced at a
 // different version. The symbol created will have New set to false, since this
 // function is only used when a parent symbol is not found for the unit symbol,
 // which means it was not introduced at the same version.
 func createParent(us *internal.UnitSymbol, pkgURLPath string) *Symbol {
 	builds := symbolBuilds(us)
 	s := &Symbol{
 		Name:     us.ParentName,
 		Synopsis: fmt.Sprintf("type %s", us.ParentName),
 		Link:     symbolLink(pkgURLPath, us.ParentName, us.BuildContexts()),
 		Section:  internal.SymbolSectionTypes,
 		Kind:     internal.SymbolKindType,
 		Builds:   builds,
 	}
 	return s
 }

 // sortSymbols returns an array of symbols in order of
 // (1) Constants (2) Variables (3) Functions and (4) Types.
 // Within each section, symbols are sorted alphabetically by name.
 // In the types sections, aside from interfaces, child symbols are sorted in
 // order of (1) Fields (2) Constants (3) Variables (4) Functions and (5)
 // Methods. For interfaces, child symbols are sorted in order of
 // (1) Methods (2) Constants (3) Variables and (4) Functions.
 func sortSymbols(nameToSymbol map[string]*Symbol) [][]*Symbol {
 	sm := map[internal.SymbolSection][]*Symbol{}
 	for _, parent := range nameToSymbol {
 		sm[parent.Section] = append(sm[parent.Section], parent)

 		cm := map[internal.SymbolKind][]*Symbol{}
 		parent.Synopsis = strings.TrimSuffix(parent.Synopsis, "{ ... }")
 		for _, c := range parent.Children {
 			cm[c.Kind] = append(cm[c.Kind], c)
 		}
 		for _, syms := range cm {
 			sortSymbolsGroup(syms)
 		}
 		symbols := append(append(append(
 			cm[internal.SymbolKindField],
 			cm[internal.SymbolKindConstant]...),
 			cm[internal.SymbolKindVariable]...),
 			cm[internal.SymbolKindFunction]...)
 		if strings.Contains(parent.Synopsis, "interface") {
 			parent.Children = append(cm[internal.SymbolKindMethod], symbols...)
 		} else {
 			parent.Children = append(symbols, cm[internal.SymbolKindMethod]...)
 		}
 	}
 	for _, syms := range sm {
 		sortSymbolsGroup(syms)
 	}

 	var out [][]*Symbol
 	for _, section := range []internal.SymbolSection{
 		internal.SymbolSectionConstants,
 		internal.SymbolSectionVariables,
 		internal.SymbolSectionFunctions,
 		internal.SymbolSectionTypes} {
 		if sm[section] != nil {
 			out = append(out, sm[section])
 		}
 	}
 	return out
 }

 func sortSymbolsGroup(syms []*Symbol) {
 	sort.Slice(syms, func(i, j int) bool {
 		return syms[i].Synopsis < syms[j].Synopsis
 	})
 	for _, s := range syms {
 		sort.Strings(s.Builds)
 	}
 }

 // ParseVersionsDetails returns a map of versionToNameToUnitSymbol based on
 // data from the proovided VersionDetails.
 func ParseVersionsDetails(vd VersionsDetails) (map[string]map[string]*internal.UnitSymbol, error) {
 	versionToNameToSymbol := map[string]map[string]*internal.UnitSymbol{}
 	for _, vl := range vd.ThisModule {
 		for _, vs := range vl.Versions {
 			v := vs.Version
 			versionToNameToSymbol[v] = map[string]*internal.UnitSymbol{}
 			for _, syms := range vs.Symbols {
 				for _, s := range syms {
 					if s.New {
 						versionToNameToSymbol[v][s.Name] = unitSymbol(s)
 					}
 					for _, c := range s.Children {
 						versionToNameToSymbol[v][c.Name] = unitSymbol(c)
 					}
 				}
 			}
 		}
 	}
 	return versionToNameToSymbol, nil
 }

 // unitSymbol returns an *internal.unitSymbol from the provided *Symbol.
 func unitSymbol(s *Symbol) *internal.UnitSymbol {
 	us := &internal.UnitSymbol{
 		SymbolMeta: internal.SymbolMeta{
 			Name: s.Name,
 		},
 	}
 	if len(s.Builds) == 0 {
 		us.AddBuildContext(internal.BuildContextAll)
 	}
 	for _, b := range s.Builds {
 		parts := strings.SplitN(b, "/", 2)
 		var build internal.BuildContext
 		switch parts[0] {
 		case "linux":
 			build = internal.BuildContextLinux
 		case "darwin":
 			build = internal.BuildContextDarwin
 		case "windows":
 			build = internal.BuildContextWindows
 		case "js":
 			build = internal.BuildContextJS
 		}
 		if us.SupportsBuild(build) {
 			fmt.Printf("duplicate build context for %q: %v\n", s.Name, build)
 		}
 		us.AddBuildContext(build)
 	}
 	return us
 }
	// Copyright 2021 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	package frontend

	import (
	"fmt"
	"sort"
	"strings"

	"golang.org/x/pkgsite/internal"
	)

	// Symbol is an element in the package API. A symbol can be a constant,
	// variable, function, type, field or method.
	type Symbol struct {
	// Name is name of the symbol. At a given package version, name must be
	// unique.
	Name string

	// Synopsis is the one line description of the symbol that is displayed.
	Synopsis string

	// Link is the link to the symbol name on pkg.go.dev.
	Link string

	// Section is the section that a symbol appears in.
	Section internal.SymbolSection

	// Kind is the type of a symbol, which is either a constant, variable,
	// function, type, field or method.
	Kind internal.SymbolKind

	// Children contain the child symbols for this symbol. This will
	// only be populated when the SymbolType is "Type". For example, the
	// children of net/http.Handler are FileServer, NotFoundHandler,
	// RedirectHandler, StripPrefix, and TimeoutHandler. Each child
	// symbol will have ParentName set to the Name of this type.
	Children []*Symbol

	// Builds lists all of the build contexts supported by the symbol, it is
	// only available for limited set of builds. If the symbol supports all
	// build contexts, Builds will be nil.
	Builds []string

	// New indicates that the symbol is new as of the version where it is
	// present. For example, if type Client was introduced in v1.0.0 and
	// Client.Timeout was introduced in v1.1.0, New will be false for Client
	// and true for Client.Timeout if this Symbol corresponds to v1.1.0.
	New bool
	}

	// symbolsForVersions returns an array of symbols for use in the VersionSummary
	// of the specified version.
	func symbolsForVersion(pkgURLPath string, symbolsAtVersion map[string]internal.UnitSymbol) [][]Symbol {
	nameToSymbol := map[string]*Symbol{}
	for _, us := range symbolsAtVersion {
	builds := symbolBuilds(us)
	s, ok := nameToSymbol[us.Name]
	if !ok {
	s = &Symbol{
	Name: us.Name,
	Synopsis: us.Synopsis,
	Link: symbolLink(pkgURLPath, us.Name, us.BuildContexts()),
	Section: us.Section,
	Kind: us.Kind,
	New: true,
	Builds: builds,
	}
	} else if !s.New && us.Kind == internal.SymbolKindType {
	// It's possible that a symbol was already created if this is a parent
	// symbol and we called addSymbol on the child symbol first. In that
	// case, a parent symbol would have been created where s.New is set to
	// false and s.Synopsis is set to the one created in createParent.
	// Update those fields instead of overwritting the struct, since the
	// struct's Children field would have already been populated.
	s.New = true
	s.Synopsis = us.Synopsis
	}
	if us.ParentName == us.Name {
	// s is not a child symbol of a type, so add it to the map and
	// continue.
	nameToSymbol[us.Name] = s
	continue
	}

	// s is a child symbol of a parent type, so append it to the Children field
	// of the parent type.
	parent, ok := nameToSymbol[us.ParentName]
	if !ok {
	parent = createParent(us, pkgURLPath)
	nameToSymbol[us.ParentName] = parent
	}
	if len(parent.Builds) == len(s.Builds) {
	s.Builds = nil
	}
	parent.Children = append(parent.Children, s)
	}
	return sortSymbols(nameToSymbol)
	}

	func symbolLink(pkgURLPath, name string, builds []internal.BuildContext) string {
	if len(builds) == len(internal.BuildContexts) {
	return fmt.Sprintf("%s#%s", pkgURLPath, name)
	}

	// When a symbol is introduced for a specific GOOS/GOARCH at a version,
	// linking to an unspecified GOOS/GOARCH page might not take the user to
	// the symbol. Instead, link to one of the supported build contexts.
	return fmt.Sprintf("%s?GOOS=%s#%s", pkgURLPath, builds[0].GOOS, name)
	}

	func symbolBuilds(us *internal.UnitSymbol) []string {
	if us.InAll() {
	return nil
	}
	var builds []string
	for _, b := range us.BuildContexts() {
	builds = append(builds, b.String())
	}
	sort.Strings(builds)
	return builds
	}

	// createParent creates a parent symbol for the provided unit symbol. This is
	// used when us is a child of a symbol that may have been introduced at a
	// different version. The symbol created will have New set to false, since this
	// function is only used when a parent symbol is not found for the unit symbol,
	// which means it was not introduced at the same version.
	func createParent(us internal.UnitSymbol, pkgURLPath string) Symbol {
	builds := symbolBuilds(us)
	s := &Symbol{
	Name: us.ParentName,
	Synopsis: fmt.Sprintf("type %s", us.ParentName),
	Link: symbolLink(pkgURLPath, us.ParentName, us.BuildContexts()),
	Section: internal.SymbolSectionTypes,
	Kind: internal.SymbolKindType,
	Builds: builds,
	}
	return s
	}

	// sortSymbols returns an array of symbols in order of
	// (1) Constants (2) Variables (3) Functions and (4) Types.
	// Within each section, symbols are sorted alphabetically by name.
	// In the types sections, aside from interfaces, child symbols are sorted in
	// order of (1) Fields (2) Constants (3) Variables (4) Functions and (5)
	// Methods. For interfaces, child symbols are sorted in order of
	// (1) Methods (2) Constants (3) Variables and (4) Functions.
	func sortSymbols(nameToSymbol map[string]Symbol) [][]Symbol {
	sm := map[internal.SymbolSection][]*Symbol{}
	for _, parent := range nameToSymbol {
	sm[parent.Section] = append(sm[parent.Section], parent)

	cm := map[internal.SymbolKind][]*Symbol{}
	parent.Synopsis = strings.TrimSuffix(parent.Synopsis, "{ ... }")
	for _, c := range parent.Children {
	cm[c.Kind] = append(cm[c.Kind], c)
	}
	for _, syms := range cm {
	sortSymbolsGroup(syms)
	}
	symbols := append(append(append(
	cm[internal.SymbolKindField],
	cm[internal.SymbolKindConstant]...),
	cm[internal.SymbolKindVariable]...),
	cm[internal.SymbolKindFunction]...)
	if strings.Contains(parent.Synopsis, "interface") {
	parent.Children = append(cm[internal.SymbolKindMethod], symbols...)
	} else {
	parent.Children = append(symbols, cm[internal.SymbolKindMethod]...)
	}
	}
	for _, syms := range sm {
	sortSymbolsGroup(syms)
	}

	var out [][]*Symbol
	for _, section := range []internal.SymbolSection{
	internal.SymbolSectionConstants,
	internal.SymbolSectionVariables,
	internal.SymbolSectionFunctions,
	internal.SymbolSectionTypes} {
	if sm[section] != nil {
	out = append(out, sm[section])
	}
	}
	return out
	}

	func sortSymbolsGroup(syms []*Symbol) {
	sort.Slice(syms, func(i, j int) bool {
	return syms[i].Synopsis < syms[j].Synopsis
	})
	for _, s := range syms {
	sort.Strings(s.Builds)
	}
	}

	// ParseVersionsDetails returns a map of versionToNameToUnitSymbol based on
	// data from the proovided VersionDetails.
	func ParseVersionsDetails(vd VersionsDetails) (map[string]map[string]*internal.UnitSymbol, error) {
	versionToNameToSymbol := map[string]map[string]*internal.UnitSymbol{}
	for _, vl := range vd.ThisModule {
	for _, vs := range vl.Versions {
	v := vs.Version
	versionToNameToSymbol[v] = map[string]*internal.UnitSymbol{}
	for _, syms := range vs.Symbols {
	for _, s := range syms {
	if s.New {
	versionToNameToSymbol[v][s.Name] = unitSymbol(s)
	}
	for _, c := range s.Children {
	versionToNameToSymbol[v][c.Name] = unitSymbol(c)
	}
	}
	}
	}
	}
	return versionToNameToSymbol, nil
	}

	// unitSymbol returns an internal.unitSymbol from the provided Symbol.
	func unitSymbol(s Symbol) internal.UnitSymbol {
	us := &internal.UnitSymbol{
	SymbolMeta: internal.SymbolMeta{
	Name: s.Name,
	},
	}
	if len(s.Builds) == 0 {
	us.AddBuildContext(internal.BuildContextAll)
	}
	for _, b := range s.Builds {
	parts := strings.SplitN(b, "/", 2)
	var build internal.BuildContext
	switch parts[0] {
	case "linux":
	build = internal.BuildContextLinux
	case "darwin":
	build = internal.BuildContextDarwin
	case "windows":
	build = internal.BuildContextWindows
	case "js":
	build = internal.BuildContextJS
	}
	if us.SupportsBuild(build) {
	fmt.Printf("duplicate build context for %q: %v\n", s.Name, build)
	}
	us.AddBuildContext(build)
	}
	return us
	}