// Copyright 2009 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 doc
import (
"cmp"
"fmt"
"go/ast"
"go/token"
"internal/lazyregexp"
"path"
"slices"
"strconv"
"strings"
"unicode"
"unicode/utf8"
)
// ----------------------------------------------------------------------------
// function/method sets
//
// Internally, we treat functions like methods and collect them in method sets.
// A methodSet describes a set of methods. Entries where Decl == nil are conflict
// entries (more than one method with the same name at the same embedding level).
type methodSet map[string]*Func
// recvString returns a string representation of recv of the form "T", "*T",
// "T[A, ...]", "*T[A, ...]" or "BADRECV" (if not a proper receiver type).
func recvString(recv ast.Expr) string {
switch t := recv.(type) {
case *ast.Ident:
return t.Name
case *ast.StarExpr:
return "*" + recvString(t.X)
case *ast.IndexExpr:
// Generic type with one parameter.
return fmt.Sprintf("%s[%s]", recvString(t.X), recvParam(t.Index))
case *ast.IndexListExpr:
// Generic type with multiple parameters.
if len(t.Indices) > 0 {
var b strings.Builder
b.WriteString(recvString(t.X))
b.WriteByte('[')
b.WriteString(recvParam(t.Indices[0]))
for _, e := range t.Indices[1:] {
b.WriteString(", ")
b.WriteString(recvParam(e))
}
b.WriteByte(']')
return b.String()
}
}
return "BADRECV"
}
func recvParam(p ast.Expr) string {
if id, ok := p.(*ast.Ident); ok {
return id.Name
}
return "BADPARAM"
}
// set creates the corresponding Func for f and adds it to mset.
// If there are multiple f's with the same name, set keeps the first
// one with documentation; conflicts are ignored. The boolean
// specifies whether to leave the AST untouched.
func (mset methodSet) set(f *ast.FuncDecl, preserveAST bool) {
name := f.Name.Name
if g := mset[name]; g != nil && g.Doc != "" {
// A function with the same name has already been registered;
// since it has documentation, assume f is simply another
// implementation and ignore it. This does not happen if the
// caller is using go/build.ScanDir to determine the list of
// files implementing a package.
return
}
// function doesn't exist or has no documentation; use f
recv := ""
if f.Recv != nil {
var typ ast.Expr
// be careful in case of incorrect ASTs
if list := f.Recv.List; len(list) == 1 {
typ = list[0].Type
}
recv = recvString(typ)
}
mset[name] = &Func{
Doc: f.Doc.Text(),
Name: name,
Decl: f,
Recv: recv,
Orig: recv,
}
if !preserveAST {
f.Doc = nil // doc consumed - remove from AST
}
}
// add adds method m to the method set; m is ignored if the method set
// already contains a method with the same name at the same or a higher
// level than m.
func (mset methodSet) add(m *Func) {
old := mset[m.Name]
if old == nil || m.Level < old.Level {
mset[m.Name] = m
return
}
if m.Level == old.Level {
// conflict - mark it using a method with nil Decl
mset[m.Name] = &Func{
Name: m.Name,
Level: m.Level,
}
}
}
// ----------------------------------------------------------------------------
// Named types
// baseTypeName returns the name of the base type of x (or "")
// and whether the type is imported or not.
func baseTypeName(x ast.Expr) (name string, imported bool) {
switch t := x.(type) {
case *ast.Ident:
return t.Name, false
case *ast.IndexExpr:
return baseTypeName(t.X)
case *ast.IndexListExpr:
return baseTypeName(t.X)
case *ast.SelectorExpr:
if _, ok := t.X.(*ast.Ident); ok {
// only possible for qualified type names;
// assume type is imported
return t.Sel.Name, true
}
case *ast.ParenExpr:
return baseTypeName(t.X)
case *ast.StarExpr:
return baseTypeName(t.X)
}
return "", false
}
// An embeddedSet describes a set of embedded types.
type embeddedSet map[*namedType]bool
// A namedType represents a named unqualified (package local, or possibly
// predeclared) type. The namedType for a type name is always found via
// reader.lookupType.
type namedType struct {
doc string // doc comment for type
name string // type name
decl *ast.GenDecl // nil if declaration hasn't been seen yet
isEmbedded bool // true if this type is embedded
isStruct bool // true if this type is a struct
embedded embeddedSet // true if the embedded type is a pointer
// associated declarations
values []*Value // consts and vars
funcs methodSet
methods methodSet
}
// ----------------------------------------------------------------------------
// AST reader
// reader accumulates documentation for a single package.
// It modifies the AST: Comments (declaration documentation)
// that have been collected by the reader are set to nil
// in the respective AST nodes so that they are not printed
// twice (once when printing the documentation and once when
// printing the corresponding AST node).
type reader struct {
mode Mode
// package properties
doc string // package documentation, if any
filenames []string
notes map[string][]*Note
// imports
imports map[string]int
hasDotImp bool // if set, package contains a dot import
importByName map[string]string
// declarations
values []*Value // consts and vars
order int // sort order of const and var declarations (when we can't use a name)
types map[string]*namedType
funcs methodSet
// support for package-local shadowing of predeclared types
shadowedPredecl map[string]bool
fixmap map[string][]*ast.InterfaceType
}
func (r *reader) isVisible(name string) bool {
return r.mode&AllDecls != 0 || token.IsExported(name)
}
// lookupType returns the base type with the given name.
// If the base type has not been encountered yet, a new
// type with the given name but no associated declaration
// is added to the type map.
func (r *reader) lookupType(name string) *namedType {
if name == "" || name == "_" {
return nil // no type docs for anonymous types
}
if typ, found := r.types[name]; found {
return typ
}
// type not found - add one without declaration
typ := &namedType{
name: name,
embedded: make(embeddedSet),
funcs: make(methodSet),
methods: make(methodSet),
}
r.types[name] = typ
return typ
}
// recordAnonymousField registers fieldType as the type of an
// anonymous field in the parent type. If the field is imported
// (qualified name) or the parent is nil, the field is ignored.
// The function returns the field name.
func (r *reader) recordAnonymousField(parent *namedType, fieldType ast.Expr) (fname string) {
fname, imp := baseTypeName(fieldType)
if parent == nil || imp {
return
}
if ftype := r.lookupType(fname); ftype != nil {
ftype.isEmbedded = true
_, ptr := fieldType.(*ast.StarExpr)
parent.embedded[ftype] = ptr
}
return
}
func (r *reader) readDoc(comment *ast.CommentGroup) {
// By convention there should be only one package comment
// but collect all of them if there are more than one.
text := comment.Text()
if r.doc == "" {
r.doc = text
return
}
r.doc += "\n" + text
}
func (r *reader) remember(predecl string, typ *ast.InterfaceType) {
if r.fixmap == nil {
r.fixmap = make(map[string][]*ast.InterfaceType)
}
r.fixmap[predecl] = append(r.fixmap[predecl], typ)
}
func specNames(specs []ast.Spec) []string {
names := make([]string, 0, len(specs)) // reasonable estimate
for _, s := range specs {
// s guaranteed to be an *ast.ValueSpec by readValue
for _, ident := range s.(*ast.ValueSpec).Names {
names = append(names, ident.Name)
}
}
return names
}
// readValue processes a const or var declaration.
func (r *reader) readValue(decl *ast.GenDecl) {
// determine if decl should be associated with a type
// Heuristic: For each typed entry, determine the type name, if any.
// If there is exactly one type name that is sufficiently
// frequent, associate the decl with the respective type.
domName := ""
domFreq := 0
prev := ""
n := 0
for _, spec := range decl.Specs {
s, ok := spec.(*ast.ValueSpec)
if !ok {
continue // should not happen, but be conservative
}
name := ""
switch {
case s.Type != nil:
// a type is present; determine its name
if n, imp := baseTypeName(s.Type); !imp {
name = n
}
case decl.Tok == token.CONST && len(s.Values) == 0:
// no type or value is present but we have a constant declaration;
// use the previous type name (possibly the empty string)
name = prev
}
if name != "" {
// entry has a named type
if domName != "" && domName != name {
// more than one type name - do not associate
// with any type
domName = ""
break
}
domName = name
domFreq++
}
prev = name
n++
}
// nothing to do w/o a legal declaration
if n == 0 {
return
}
// determine values list with which to associate the Value for this decl
values := &r.values
const threshold = 0.75
if domName != "" && r.isVisible(domName) && domFreq >= int(float64(len(decl.Specs))*threshold) {
// typed entries are sufficiently frequent
if typ := r.lookupType(domName); typ != nil {
values = &typ.values // associate with that type
}
}
*values = append(*values, &Value{
Doc: decl.Doc.Text(),
Names: specNames(decl.Specs),
Decl: decl,
order: r.order,
})
if r.mode&PreserveAST == 0 {
decl.Doc = nil // doc consumed - remove from AST
}
// Note: It's important that the order used here is global because the cleanupTypes
// methods may move values associated with types back into the global list. If the
// order is list-specific, sorting is not deterministic because the same order value
// may appear multiple times (was bug, found when fixing #16153).
r.order++
}
// fields returns a struct's fields or an interface's methods.
func fields(typ ast.Expr) (list []*ast.Field, isStruct bool) {
var fields *ast.FieldList
switch t := typ.(type) {
case *ast.StructType:
fields = t.Fields
isStruct = true
case *ast.InterfaceType:
fields = t.Methods
}
if fields != nil {
list = fields.List
}
return
}
// readType processes a type declaration.
func (r *reader) readType(decl *ast.GenDecl, spec *ast.TypeSpec) {
typ := r.lookupType(spec.Name.Name)
if typ == nil {
return // no name or blank name - ignore the type
}
// A type should be added at most once, so typ.decl
// should be nil - if it is not, simply overwrite it.
typ.decl = decl
// compute documentation
doc := spec.Doc
if doc == nil {
// no doc associated with the spec, use the declaration doc, if any
doc = decl.Doc
}
if r.mode&PreserveAST == 0 {
spec.Doc = nil // doc consumed - remove from AST
decl.Doc = nil // doc consumed - remove from AST
}
typ.doc = doc.Text()
// record anonymous fields (they may contribute methods)
// (some fields may have been recorded already when filtering
// exports, but that's ok)
var list []*ast.Field
list, typ.isStruct = fields(spec.Type)
for _, field := range list {
if len(field.Names) == 0 {
r.recordAnonymousField(typ, field.Type)
}
}
}
// isPredeclared reports whether n denotes a predeclared type.
func (r *reader) isPredeclared(n string) bool {
return predeclaredTypes[n] && r.types[n] == nil
}
// readFunc processes a func or method declaration.
func (r *reader) readFunc(fun *ast.FuncDecl) {
// strip function body if requested.
if r.mode&PreserveAST == 0 {
fun.Body = nil
}
// associate methods with the receiver type, if any
if fun.Recv != nil {
// method
if len(fun.Recv.List) == 0 {
// should not happen (incorrect AST); (See issue 17788)
// don't show this method
return
}
recvTypeName, imp := baseTypeName(fun.Recv.List[0].Type)
if imp {
// should not happen (incorrect AST);
// don't show this method
return
}
if typ := r.lookupType(recvTypeName); typ != nil {
typ.methods.set(fun, r.mode&PreserveAST != 0)
}
// otherwise ignore the method
// TODO(gri): There may be exported methods of non-exported types
// that can be called because of exported values (consts, vars, or
// function results) of that type. Could determine if that is the
// case and then show those methods in an appropriate section.
return
}
// Associate factory functions with the first visible result type, as long as
// others are predeclared types.
if fun.Type.Results.NumFields() >= 1 {
var typ *namedType // type to associate the function with
numResultTypes := 0
for _, res := range fun.Type.Results.List {
factoryType := res.Type
if t, ok := factoryType.(*ast.ArrayType); ok {
// We consider functions that return slices or arrays of type
// T (or pointers to T) as factory functions of T.
factoryType = t.Elt
}
if n, imp := baseTypeName(factoryType); !imp && r.isVisible(n) && !r.isPredeclared(n) {
if lookupTypeParam(n, fun.Type.TypeParams) != nil {
// Issue #49477: don't associate fun with its type parameter result.
// A type parameter is not a defined type.
continue
}
if t := r.lookupType(n); t != nil {
typ = t
numResultTypes++
if numResultTypes > 1 {
break
}
}
}
}
// If there is exactly one result type,
// associate the function with that type.
if numResultTypes == 1 {
typ.funcs.set(fun, r.mode&PreserveAST != 0)
return
}
}
// just an ordinary function
r.funcs.set(fun, r.mode&PreserveAST != 0)
}
// lookupTypeParam searches for type parameters named name within the tparams
// field list, returning the relevant identifier if found, or nil if not.
func lookupTypeParam(name string, tparams *ast.FieldList) *ast.Ident {
if tparams == nil {
return nil
}
for _, field := range tparams.List {
for _, id := range field.Names {
if id.Name == name {
return id
}
}
}
return nil
}
var (
noteMarker = `([A-Z][A-Z]+)\(([^)]+)\):?` // MARKER(uid), MARKER at least 2 chars, uid at least 1 char
noteMarkerRx = lazyregexp.New(`^[ \t]*` + noteMarker) // MARKER(uid) at text start
noteCommentRx = lazyregexp.New(`^/[/*][ \t]*` + noteMarker) // MARKER(uid) at comment start
)
// clean replaces each sequence of space, \r, or \t characters
// with a single space and removes any trailing and leading spaces.
func clean(s string) string {
var b []byte
p := byte(' ')
for i := 0; i < len(s); i++ {
q := s[i]
if q == '\r' || q == '\t' {
q = ' '
}
if q != ' ' || p != ' ' {
b = append(b, q)
p = q
}
}
// remove trailing blank, if any
if n := len(b); n > 0 && p == ' ' {
b = b[0 : n-1]
}
return string(b)
}
// readNote collects a single note from a sequence of comments.
func (r *reader) readNote(list []*ast.Comment) {
text := (&ast.CommentGroup{List: list}).Text()
if m := noteMarkerRx.FindStringSubmatchIndex(text); m != nil {
// The note body starts after the marker.
// We remove any formatting so that we don't
// get spurious line breaks/indentation when
// showing the TODO body.
body := clean(text[m[1]:])
if body != "" {
marker := text[m[2]:m[3]]
r.notes[marker] = append(r.notes[marker], &Note{
Pos: list[0].Pos(),
End: list[len(list)-1].End(),
UID: text[m[4]:m[5]],
Body: body,
})
}
}
}
// readNotes extracts notes from comments.
// A note must start at the beginning of a comment with "MARKER(uid):"
// and is followed by the note body (e.g., "// BUG(gri): fix this").
// The note ends at the end of the comment group or at the start of
// another note in the same comment group, whichever comes first.
func (r *reader) readNotes(comments []*ast.CommentGroup) {
for _, group := range comments {
i := -1 // comment index of most recent note start, valid if >= 0
list := group.List
for j, c := range list {
if noteCommentRx.MatchString(c.Text) {
if i >= 0 {
r.readNote(list[i:j])
}
i = j
}
}
if i >= 0 {
r.readNote(list[i:])
}
}
}
// readFile adds the AST for a source file to the reader.
func (r *reader) readFile(src *ast.File) {
// add package documentation
if src.Doc != nil {
r.readDoc(src.Doc)
if r.mode&PreserveAST == 0 {
src.Doc = nil // doc consumed - remove from AST
}
}
// add all declarations but for functions which are processed in a separate pass
for _, decl := range src.Decls {
switch d := decl.(type) {
case *ast.GenDecl:
switch d.Tok {
case token.IMPORT:
// imports are handled individually
for _, spec := range d.Specs {
if s, ok := spec.(*ast.ImportSpec); ok {
if import_, err := strconv.Unquote(s.Path.Value); err == nil {
r.imports[import_] = 1
var name string
if s.Name != nil {
name = s.Name.Name
if name == "." {
r.hasDotImp = true
}
}
if name != "." {
if name == "" {
name = assumedPackageName(import_)
}
old, ok := r.importByName[name]
if !ok {
r.importByName[name] = import_
} else if old != import_ && old != "" {
r.importByName[name] = "" // ambiguous
}
}
}
}
}
case token.CONST, token.VAR:
// constants and variables are always handled as a group
r.readValue(d)
case token.TYPE:
// types are handled individually
if len(d.Specs) == 1 && !d.Lparen.IsValid() {
// common case: single declaration w/o parentheses
// (if a single declaration is parenthesized,
// create a new fake declaration below, so that
// go/doc type declarations always appear w/o
// parentheses)
if s, ok := d.Specs[0].(*ast.TypeSpec); ok {
r.readType(d, s)
}
break
}
for _, spec := range d.Specs {
if s, ok := spec.(*ast.TypeSpec); ok {
// use an individual (possibly fake) declaration
// for each type; this also ensures that each type
// gets to (re-)use the declaration documentation
// if there's none associated with the spec itself
fake := &ast.GenDecl{
Doc: d.Doc,
// don't use the existing TokPos because it
// will lead to the wrong selection range for
// the fake declaration if there are more
// than one type in the group (this affects
// src/cmd/godoc/godoc.go's posLink_urlFunc)
TokPos: s.Pos(),
Tok: token.TYPE,
Specs: []ast.Spec{s},
}
r.readType(fake, s)
}
}
}
}
}
// collect MARKER(...): annotations
r.readNotes(src.Comments)
if r.mode&PreserveAST == 0 {
src.Comments = nil // consumed unassociated comments - remove from AST
}
}
func (r *reader) readPackage(pkg *ast.Package, mode Mode) {
// initialize reader
r.filenames = make([]string, len(pkg.Files))
r.imports = make(map[string]int)
r.mode = mode
r.types = make(map[string]*namedType)
r.funcs = make(methodSet)
r.notes = make(map[string][]*Note)
r.importByName = make(map[string]string)
// sort package files before reading them so that the
// result does not depend on map iteration order
i := 0
for filename := range pkg.Files {
r.filenames[i] = filename
i++
}
slices.Sort(r.filenames)
// process files in sorted order
for _, filename := range r.filenames {
f := pkg.Files[filename]
if mode&AllDecls == 0 {
r.fileExports(f)
}
r.readFile(f)
}
for name, path := range r.importByName {
if path == "" {
delete(r.importByName, name)
}
}
// process functions now that we have better type information
for _, f := range pkg.Files {
for _, decl := range f.Decls {
if d, ok := decl.(*ast.FuncDecl); ok {
r.readFunc(d)
}
}
}
}
// ----------------------------------------------------------------------------
// Types
func customizeRecv(f *Func, recvTypeName string, embeddedIsPtr bool, level int) *Func {
if f == nil || f.Decl == nil || f.Decl.Recv == nil || len(f.Decl.Recv.List) != 1 {
return f // shouldn't happen, but be safe
}
// copy existing receiver field and set new type
newField := *f.Decl.Recv.List[0]
origPos := newField.Type.Pos()
_, origRecvIsPtr := newField.Type.(*ast.StarExpr)
newIdent := &ast.Ident{NamePos: origPos, Name: recvTypeName}
var typ ast.Expr = newIdent
if !embeddedIsPtr && origRecvIsPtr {
newIdent.NamePos++ // '*' is one character
typ = &ast.StarExpr{Star: origPos, X: newIdent}
}
newField.Type = typ
// copy existing receiver field list and set new receiver field
newFieldList := *f.Decl.Recv
newFieldList.List = []*ast.Field{&newField}
// copy existing function declaration and set new receiver field list
newFuncDecl := *f.Decl
newFuncDecl.Recv = &newFieldList
// copy existing function documentation and set new declaration
newF := *f
newF.Decl = &newFuncDecl
newF.Recv = recvString(typ)
// the Orig field never changes
newF.Level = level
return &newF
}
// collectEmbeddedMethods collects the embedded methods of typ in mset.
func (r *reader) collectEmbeddedMethods(mset methodSet, typ *namedType, recvTypeName string, embeddedIsPtr bool, level int, visited embeddedSet) {
visited[typ] = true
for embedded, isPtr := range typ.embedded {
// Once an embedded type is embedded as a pointer type
// all embedded types in those types are treated like
// pointer types for the purpose of the receiver type
// computation; i.e., embeddedIsPtr is sticky for this
// embedding hierarchy.
thisEmbeddedIsPtr := embeddedIsPtr || isPtr
for _, m := range embedded.methods {
// only top-level methods are embedded
if m.Level == 0 {
mset.add(customizeRecv(m, recvTypeName, thisEmbeddedIsPtr, level))
}
}
if !visited[embedded] {
r.collectEmbeddedMethods(mset, embedded, recvTypeName, thisEmbeddedIsPtr, level+1, visited)
}
}
delete(visited, typ)
}
// computeMethodSets determines the actual method sets for each type encountered.
func (r *reader) computeMethodSets() {
for _, t := range r.types {
// collect embedded methods for t
if t.isStruct {
// struct
r.collectEmbeddedMethods(t.methods, t, t.name, false, 1, make(embeddedSet))
} else {
// interface
// TODO(gri) fix this
}
}
// For any predeclared names that are declared locally, don't treat them as
// exported fields anymore.
for predecl := range r.shadowedPredecl {
for _, ityp := range r.fixmap[predecl] {
removeAnonymousField(predecl, ityp)
}
}
}
// cleanupTypes removes the association of functions and methods with
// types that have no declaration. Instead, these functions and methods
// are shown at the package level. It also removes types with missing
// declarations or which are not visible.
func (r *reader) cleanupTypes() {
for _, t := range r.types {
visible := r.isVisible(t.name)
predeclared := predeclaredTypes[t.name]
if t.decl == nil && (predeclared || visible && (t.isEmbedded || r.hasDotImp)) {
// t.name is a predeclared type (and was not redeclared in this package),
// or it was embedded somewhere but its declaration is missing (because
// the AST is incomplete), or we have a dot-import (and all bets are off):
// move any associated values, funcs, and methods back to the top-level so
// that they are not lost.
// 1) move values
r.values = append(r.values, t.values...)
// 2) move factory functions
for name, f := range t.funcs {
// in a correct AST, package-level function names
// are all different - no need to check for conflicts
r.funcs[name] = f
}
// 3) move methods
if !predeclared {
for name, m := range t.methods {
// don't overwrite functions with the same name - drop them
if _, found := r.funcs[name]; !found {
r.funcs[name] = m
}
}
}
}
// remove types w/o declaration or which are not visible
if t.decl == nil || !visible {
delete(r.types, t.name)
}
}
}
// ----------------------------------------------------------------------------
// Sorting
func sortedKeys(m map[string]int) []string {
list := make([]string, len(m))
i := 0
for key := range m {
list[i] = key
i++
}
slices.Sort(list)
return list
}
// sortingName returns the name to use when sorting d into place.
func sortingName(d *ast.GenDecl) string {
if len(d.Specs) == 1 {
if s, ok := d.Specs[0].(*ast.ValueSpec); ok {
return s.Names[0].Name
}
}
return ""
}
func sortedValues(m []*Value, tok token.Token) []*Value {
list := make([]*Value, len(m)) // big enough in any case
i := 0
for _, val := range m {
if val.Decl.Tok == tok {
list[i] = val
i++
}
}
list = list[0:i]
slices.SortFunc(list, func(a, b *Value) int {
r := strings.Compare(sortingName(a.Decl), sortingName(b.Decl))
if r != 0 {
return r
}
return cmp.Compare(a.order, b.order)
})
return list
}
func sortedTypes(m map[string]*namedType, allMethods bool) []*Type {
list := make([]*Type, len(m))
i := 0
for _, t := range m {
list[i] = &Type{
Doc: t.doc,
Name: t.name,
Decl: t.decl,
Consts: sortedValues(t.values, token.CONST),
Vars: sortedValues(t.values, token.VAR),
Funcs: sortedFuncs(t.funcs, true),
Methods: sortedFuncs(t.methods, allMethods),
}
i++
}
slices.SortFunc(list, func(a, b *Type) int {
return strings.Compare(a.Name, b.Name)
})
return list
}
func removeStar(s string) string {
if len(s) > 0 && s[0] == '*' {
return s[1:]
}
return s
}
func sortedFuncs(m methodSet, allMethods bool) []*Func {
list := make([]*Func, len(m))
i := 0
for _, m := range m {
// determine which methods to include
switch {
case m.Decl == nil:
// exclude conflict entry
case allMethods, m.Level == 0, !token.IsExported(removeStar(m.Orig)):
// forced inclusion, method not embedded, or method
// embedded but original receiver type not exported
list[i] = m
i++
}
}
list = list[0:i]
slices.SortFunc(list, func(a, b *Func) int {
return strings.Compare(a.Name, b.Name)
})
return list
}
// noteBodies returns a list of note body strings given a list of notes.
// This is only used to populate the deprecated Package.Bugs field.
func noteBodies(notes []*Note) []string {
var list []string
for _, n := range notes {
list = append(list, n.Body)
}
return list
}
// ----------------------------------------------------------------------------
// Predeclared identifiers
// IsPredeclared reports whether s is a predeclared identifier.
func IsPredeclared(s string) bool {
return predeclaredTypes[s] || predeclaredFuncs[s] || predeclaredConstants[s]
}
var predeclaredTypes = map[string]bool{
"any": true,
"bool": true,
"byte": true,
"comparable": true,
"complex64": true,
"complex128": true,
"error": true,
"float32": true,
"float64": true,
"int": true,
"int8": true,
"int16": true,
"int32": true,
"int64": true,
"rune": true,
"string": true,
"uint": true,
"uint8": true,
"uint16": true,
"uint32": true,
"uint64": true,
"uintptr": true,
}
var predeclaredFuncs = map[string]bool{
"append": true,
"cap": true,
"clear": true,
"close": true,
"complex": true,
"copy": true,
"delete": true,
"imag": true,
"len": true,
"make": true,
"max": true,
"min": true,
"new": true,
"panic": true,
"print": true,
"println": true,
"real": true,
"recover": true,
}
var predeclaredConstants = map[string]bool{
"false": true,
"iota": true,
"nil": true,
"true": true,
}
// assumedPackageName returns the assumed package name
// for a given import path. This is a copy of
// golang.org/x/tools/internal/imports.ImportPathToAssumedName.
func assumedPackageName(importPath string) string {
notIdentifier := func(ch rune) bool {
return !('a' <= ch && ch <= 'z' || 'A' <= ch && ch <= 'Z' ||
'0' <= ch && ch <= '9' ||
ch == '_' ||
ch >= utf8.RuneSelf && (unicode.IsLetter(ch) || unicode.IsDigit(ch)))
}
base := path.Base(importPath)
if strings.HasPrefix(base, "v") {
if _, err := strconv.Atoi(base[1:]); err == nil {
dir := path.Dir(importPath)
if dir != "." {
base = path.Base(dir)
}
}
}
base = strings.TrimPrefix(base, "go-")
if i := strings.IndexFunc(base, notIdentifier); i >= 0 {
base = base[:i]
}
return base
}