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-rw-r--r--vendor/modernc.org/strutil/strutil.go733
1 files changed, 733 insertions, 0 deletions
diff --git a/vendor/modernc.org/strutil/strutil.go b/vendor/modernc.org/strutil/strutil.go
new file mode 100644
index 00000000..7d07b799
--- /dev/null
+++ b/vendor/modernc.org/strutil/strutil.go
@@ -0,0 +1,733 @@
+// Copyright (c) 2014 The sortutil 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 strutil collects utils supplemental to the standard strings package.
+package strutil // import "modernc.org/strutil"
+
+import (
+ "bytes"
+ "encoding/base32"
+ "encoding/base64"
+ "fmt"
+ "io"
+ "os"
+ "path/filepath"
+ "reflect"
+ "runtime"
+ "sort"
+ "strconv"
+ "strings"
+ "sync"
+)
+
+// Base32ExtDecode decodes base32 extended (RFC 4648) text to binary data.
+func Base32ExtDecode(text []byte) (data []byte, err error) {
+ n := base32.HexEncoding.DecodedLen(len(text))
+ data = make([]byte, n)
+ decoder := base32.NewDecoder(base32.HexEncoding, bytes.NewBuffer(text))
+ if n, err = decoder.Read(data); err != nil {
+ n = 0
+ }
+ data = data[:n]
+ return
+}
+
+// Base32ExtEncode encodes binary data to base32 extended (RFC 4648) encoded text.
+func Base32ExtEncode(data []byte) (text []byte) {
+ n := base32.HexEncoding.EncodedLen(len(data))
+ buf := bytes.NewBuffer(make([]byte, 0, n))
+ encoder := base32.NewEncoder(base32.HexEncoding, buf)
+ encoder.Write(data)
+ encoder.Close()
+ if buf.Len() != n {
+ panic("internal error")
+ }
+ return buf.Bytes()
+}
+
+// Base64Decode decodes base64 text to binary data.
+func Base64Decode(text []byte) (data []byte, err error) {
+ n := base64.StdEncoding.DecodedLen(len(text))
+ data = make([]byte, n)
+ decoder := base64.NewDecoder(base64.StdEncoding, bytes.NewBuffer(text))
+ if n, err = decoder.Read(data); err != nil {
+ n = 0
+ }
+ data = data[:n]
+ return
+}
+
+// Base64Encode encodes binary data to base64 encoded text.
+func Base64Encode(data []byte) (text []byte) {
+ n := base64.StdEncoding.EncodedLen(len(data))
+ buf := bytes.NewBuffer(make([]byte, 0, n))
+ encoder := base64.NewEncoder(base64.StdEncoding, buf)
+ encoder.Write(data)
+ encoder.Close()
+ if buf.Len() != n {
+ panic("internal error")
+ }
+ return buf.Bytes()
+}
+
+// Formatter is an io.Writer extended by a fmt.Printf like function Format
+type Formatter interface {
+ io.Writer
+ Format(format string, args ...interface{}) (n int, errno error)
+}
+
+type indentFormatter struct {
+ io.Writer
+ indent []byte
+ indentLevel int
+ state int
+}
+
+const (
+ st0 = iota
+ stBOL
+ stPERC
+ stBOLPERC
+)
+
+// IndentFormatter returns a new Formatter which interprets %i and %u in the
+// Format() format string as indent and undent commands. The commands can
+// nest. The Formatter writes to io.Writer 'w' and inserts one 'indent'
+// string per current indent level value.
+// Behaviour of commands reaching negative indent levels is undefined.
+// IndentFormatter(os.Stdout, "\t").Format("abc%d%%e%i\nx\ny\n%uz\n", 3)
+// output:
+// abc3%e
+// x
+// y
+// z
+// The Go quoted string literal form of the above is:
+// "abc%%e\n\tx\n\tx\nz\n"
+// The commands can be scattered between separate invocations of Format(),
+// i.e. the formatter keeps track of the indent level and knows if it is
+// positioned on start of a line and should emit indentation(s).
+// The same output as above can be produced by e.g.:
+// f := IndentFormatter(os.Stdout, " ")
+// f.Format("abc%d%%e%i\nx\n", 3)
+// f.Format("y\n%uz\n")
+func IndentFormatter(w io.Writer, indent string) Formatter {
+ return &indentFormatter{w, []byte(indent), 0, stBOL}
+}
+
+func (f *indentFormatter) format(flat bool, format string, args ...interface{}) (n int, errno error) {
+ buf := []byte{}
+ for i := 0; i < len(format); i++ {
+ c := format[i]
+ switch f.state {
+ case st0:
+ switch c {
+ case '\n':
+ cc := c
+ if flat && f.indentLevel != 0 {
+ cc = ' '
+ }
+ buf = append(buf, cc)
+ f.state = stBOL
+ case '%':
+ f.state = stPERC
+ default:
+ buf = append(buf, c)
+ }
+ case stBOL:
+ switch c {
+ case '\n':
+ cc := c
+ if flat && f.indentLevel != 0 {
+ cc = ' '
+ }
+ buf = append(buf, cc)
+ case '%':
+ f.state = stBOLPERC
+ default:
+ if !flat {
+ for i := 0; i < f.indentLevel; i++ {
+ buf = append(buf, f.indent...)
+ }
+ }
+ buf = append(buf, c)
+ f.state = st0
+ }
+ case stBOLPERC:
+ switch c {
+ case 'i':
+ f.indentLevel++
+ f.state = stBOL
+ case 'u':
+ f.indentLevel--
+ f.state = stBOL
+ default:
+ if !flat {
+ for i := 0; i < f.indentLevel; i++ {
+ buf = append(buf, f.indent...)
+ }
+ }
+ buf = append(buf, '%', c)
+ f.state = st0
+ }
+ case stPERC:
+ switch c {
+ case 'i':
+ f.indentLevel++
+ f.state = st0
+ case 'u':
+ f.indentLevel--
+ f.state = st0
+ default:
+ buf = append(buf, '%', c)
+ f.state = st0
+ }
+ default:
+ panic("unexpected state")
+ }
+ }
+ switch f.state {
+ case stPERC, stBOLPERC:
+ buf = append(buf, '%')
+ }
+ return f.Write([]byte(fmt.Sprintf(string(buf), args...)))
+}
+
+func (f *indentFormatter) Format(format string, args ...interface{}) (n int, errno error) {
+ return f.format(false, format, args...)
+}
+
+type flatFormatter indentFormatter
+
+// FlatFormatter returns a newly created Formatter with the same functionality as the one returned
+// by IndentFormatter except it allows a newline in the 'format' string argument of Format
+// to pass through iff indent level is currently zero.
+//
+// If indent level is non-zero then such new lines are changed to a space character.
+// There is no indent string, the %i and %u format verbs are used solely to determine the indent level.
+//
+// The FlatFormatter is intended for flattening of normally nested structure textual representation to
+// a one top level structure per line form.
+// FlatFormatter(os.Stdout, " ").Format("abc%d%%e%i\nx\ny\n%uz\n", 3)
+// output in the form of a Go quoted string literal:
+// "abc3%%e x y z\n"
+func FlatFormatter(w io.Writer) Formatter {
+ return (*flatFormatter)(IndentFormatter(w, "").(*indentFormatter))
+}
+
+func (f *flatFormatter) Format(format string, args ...interface{}) (n int, errno error) {
+ return (*indentFormatter)(f).format(true, format, args...)
+}
+
+// Pool handles aligning of strings having equal values to the same string instance.
+// Intended use is to conserve some memory e.g. where a large number of identically valued strings
+// with non identical backing arrays may exists in several semantically distinct instances of some structs.
+// Pool is *not* concurrent access safe. It doesn't handle common prefix/suffix aligning,
+// e.g. having s1 == "abc" and s2 == "bc", s2 is not automatically aligned as s1[1:].
+type Pool struct {
+ pool map[string]string
+}
+
+// NewPool returns a newly created Pool.
+func NewPool() *Pool {
+ return &Pool{map[string]string{}}
+}
+
+// Align returns a string with the same value as its argument. It guarantees that
+// all aligned strings share a single instance in memory.
+func (p *Pool) Align(s string) string {
+ if a, ok := p.pool[s]; ok {
+ return a
+ }
+
+ s = StrPack(s)
+ p.pool[s] = s
+ return s
+}
+
+// Count returns the number of items in the pool.
+func (p *Pool) Count() int {
+ return len(p.pool)
+}
+
+// GoPool is a concurrent access safe version of Pool.
+type GoPool struct {
+ pool map[string]string
+ rwm *sync.RWMutex
+}
+
+// NewGoPool returns a newly created GoPool.
+func NewGoPool() (p *GoPool) {
+ return &GoPool{map[string]string{}, &sync.RWMutex{}}
+}
+
+// Align returns a string with the same value as its argument. It guarantees that
+// all aligned strings share a single instance in memory.
+func (p *GoPool) Align(s string) (y string) {
+ if s != "" {
+ p.rwm.RLock() // R++
+ if a, ok := p.pool[s]; ok { // found
+ p.rwm.RUnlock() // R--
+ return a
+ }
+
+ p.rwm.RUnlock() // R--
+ // not found but with a race condition, retry within a write lock
+ p.rwm.Lock() // W++
+ defer p.rwm.Unlock() // W--
+ if a, ok := p.pool[s]; ok { // done in a race
+ return a
+ }
+
+ // we won
+ s = StrPack(s)
+ p.pool[s] = s
+ return s
+ }
+
+ return
+}
+
+// Count returns the number of items in the pool.
+func (p *GoPool) Count() int {
+ return len(p.pool)
+}
+
+// Dict is a string <-> id bijection. Dict is *not* concurrent access safe for assigning new ids
+// to strings not yet contained in the bijection.
+// Id for an empty string is guaranteed to be 0,
+// thus Id for any non empty string is guaranteed to be non zero.
+type Dict struct {
+ si map[string]int
+ is []string
+}
+
+// NewDict returns a newly created Dict.
+func NewDict() (d *Dict) {
+ d = &Dict{map[string]int{}, []string{}}
+ d.Id("")
+ return
+}
+
+// Count returns the number of items in the dict.
+func (d *Dict) Count() int {
+ return len(d.is)
+}
+
+// Id maps string s to its numeric identificator.
+func (d *Dict) Id(s string) (y int) {
+ if y, ok := d.si[s]; ok {
+ return y
+ }
+
+ s = StrPack(s)
+ y = len(d.is)
+ d.si[s] = y
+ d.is = append(d.is, s)
+ return
+}
+
+// S maps an id to its string value and ok == true. Id values not contained in the bijection
+// return "", false.
+func (d *Dict) S(id int) (s string, ok bool) {
+ if id >= len(d.is) {
+ return "", false
+ }
+ return d.is[id], true
+}
+
+// GoDict is a concurrent access safe version of Dict.
+type GoDict struct {
+ si map[string]int
+ is []string
+ rwm *sync.RWMutex
+}
+
+// NewGoDict returns a newly created GoDict.
+func NewGoDict() (d *GoDict) {
+ d = &GoDict{map[string]int{}, []string{}, &sync.RWMutex{}}
+ d.Id("")
+ return
+}
+
+// Count returns the number of items in the dict.
+func (d *GoDict) Count() int {
+ return len(d.is)
+}
+
+// Id maps string s to its numeric identificator. The implementation honors getting
+// an existing id at the cost of assigning a new one.
+func (d *GoDict) Id(s string) (y int) {
+ d.rwm.RLock() // R++
+ if y, ok := d.si[s]; ok { // found
+ d.rwm.RUnlock() // R--
+ return y
+ }
+
+ d.rwm.RUnlock() // R--
+
+ // not found but with a race condition
+ d.rwm.Lock() // W++ recheck with write lock
+ defer d.rwm.Unlock() // W--
+ if y, ok := d.si[s]; ok { // some other goroutine won already
+ return y
+ }
+
+ // a race free not found state => insert the string
+ s = StrPack(s)
+ y = len(d.is)
+ d.si[s] = y
+ d.is = append(d.is, s)
+ return
+}
+
+// S maps an id to its string value and ok == true. Id values not contained in the bijection
+// return "", false.
+func (d *GoDict) S(id int) (s string, ok bool) {
+ d.rwm.RLock() // R++
+ defer d.rwm.RUnlock() // R--
+ if id >= len(d.is) {
+ return "", false
+ }
+ return d.is[id], true
+}
+
+// StrPack returns a new instance of s which is tightly packed in memory.
+// It is intended for avoiding the situation where having a live reference
+// to a string slice over an unreferenced biger underlying string keeps the biger one
+// in memory anyway - it can't be GCed.
+func StrPack(s string) string {
+ return string([]byte(s)) // T(U(T)) intentional.
+}
+
+// JoinFields returns strings in flds joined by sep. Flds may contain arbitrary
+// bytes, including the sep as they are safely escaped. JoinFields panics if
+// sep is the backslash character or if len(sep) != 1.
+func JoinFields(flds []string, sep string) string {
+ if len(sep) != 1 || sep == "\\" {
+ panic("invalid separator")
+ }
+
+ a := make([]string, len(flds))
+ for i, v := range flds {
+ v = strings.Replace(v, "\\", "\\0", -1)
+ a[i] = strings.Replace(v, sep, "\\1", -1)
+ }
+ return strings.Join(a, sep)
+}
+
+// SplitFields splits s, which must be produced by JoinFields using the same
+// sep, into flds. SplitFields panics if sep is the backslash character or if
+// len(sep) != 1.
+func SplitFields(s, sep string) (flds []string) {
+ if len(sep) != 1 || sep == "\\" {
+ panic("invalid separator")
+ }
+
+ a := strings.Split(s, sep)
+ r := make([]string, len(a))
+ for i, v := range a {
+ v = strings.Replace(v, "\\1", sep, -1)
+ r[i] = strings.Replace(v, "\\0", "\\", -1)
+ }
+ return r
+}
+
+// PrettyPrintHooks allow to customize the result of PrettyPrint for types
+// listed in the map value.
+type PrettyPrintHooks map[reflect.Type]func(f Formatter, v interface{}, prefix, suffix string)
+
+// PrettyString returns the output of PrettyPrint as a string.
+func PrettyString(v interface{}, prefix, suffix string, hooks PrettyPrintHooks) string {
+ var b bytes.Buffer
+ PrettyPrint(&b, v, prefix, suffix, hooks)
+ return b.String()
+}
+
+// PrettyPrint pretty prints v to w. Zero values and unexported struct fields
+// are omitted.
+//
+// Force printing of zero values of struct fields by including in the field tag
+// PrettyPrint:"zero".
+//
+// Enable using a String method, if any, of a struct field type by including in
+// the field tag PrettyPrint:"stringer".
+//
+// The tags can be combined as in PrettyPrint:"zero,stringer". The order is not
+// important, so PrettyPrint:stringer,zero has the same effect.
+//
+// A hook attached to the field type has priority over the struct field tag
+// described above.
+func PrettyPrint(w io.Writer, v interface{}, prefix, suffix string, hooks PrettyPrintHooks) {
+ if v == nil {
+ return
+ }
+
+ f := IndentFormatter(w, "· ")
+
+ defer func() {
+ if e := recover(); e != nil {
+ f.Format("\npanic: %v", e)
+ }
+ }()
+
+ prettyPrint(nil, f, prefix, suffix, v, hooks, false, false)
+}
+
+func prettyPrint(protect map[interface{}]struct{}, sf Formatter, prefix, suffix string, v interface{}, hooks PrettyPrintHooks, zero, stringer bool) {
+ if v == nil {
+ return
+ }
+
+ rt := reflect.TypeOf(v)
+ if handler := hooks[rt]; handler != nil {
+ handler(sf, v, prefix, suffix)
+ return
+ }
+
+ rv := reflect.ValueOf(v)
+ if stringer {
+ if _, ok := v.(fmt.Stringer); ok {
+ sf.Format("%s%s", prefix, v)
+ sf.Format(suffix)
+ return
+ }
+ }
+
+ switch rt.Kind() {
+ case reflect.Slice:
+ if rv.Len() == 0 && !zero {
+ return
+ }
+
+ sf.Format("%s[]%T{ // len %d%i\n", prefix, rv.Index(0).Interface(), rv.Len())
+ for i := 0; i < rv.Len(); i++ {
+ prettyPrint(protect, sf, fmt.Sprintf("%d: ", i), ",\n", rv.Index(i).Interface(), hooks, false, false)
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%u}" + suffix)
+ case reflect.Array:
+ if reflect.Zero(rt).Interface() == rv.Interface() && !zero {
+ return
+ }
+
+ sf.Format("%s[%d]%T{%i\n", prefix, rv.Len(), rv.Index(0).Interface())
+ for i := 0; i < rv.Len(); i++ {
+ prettyPrint(protect, sf, fmt.Sprintf("%d: ", i), ",\n", rv.Index(i).Interface(), hooks, false, false)
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%u}" + suffix)
+ case reflect.Struct:
+ if rt.NumField() == 0 {
+ return
+ }
+
+ if reflect.DeepEqual(reflect.Zero(rt).Interface(), rv.Interface()) && !zero {
+ return
+ }
+
+ sf.Format("%s%T{%i\n", prefix, v)
+ for i := 0; i < rt.NumField(); i++ {
+ f := rv.Field(i)
+ if !f.CanInterface() {
+ continue
+ }
+
+ var stringer, zero bool
+ ft := rt.Field(i)
+ if tag, ok := ft.Tag.Lookup("PrettyPrint"); ok {
+ a := strings.Split(tag, ",")
+ for _, v := range a {
+ switch strings.TrimSpace(v) {
+ case "stringer":
+ stringer = true
+ case "zero":
+ zero = true
+ }
+ }
+ }
+ prettyPrint(protect, sf, fmt.Sprintf("%s: ", rt.Field(i).Name), ",\n", f.Interface(), hooks, zero, stringer)
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%u}" + suffix)
+ case reflect.Ptr:
+ if rv.IsNil() && !zero {
+ return
+ }
+
+ rvi := rv.Interface()
+ if _, ok := protect[rvi]; ok {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s&%T{ /* recursive/repetitive pointee not shown */ }"+suffix, prefix, rv.Elem().Interface())
+ return
+ }
+
+ if protect == nil {
+ protect = map[interface{}]struct{}{}
+ }
+ protect[rvi] = struct{}{}
+ prettyPrint(protect, sf, prefix+"&", suffix, rv.Elem().Interface(), hooks, false, false)
+ case reflect.Int, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int8:
+ if v := rv.Int(); v != 0 || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, v)
+ }
+ case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint8:
+ if v := rv.Uint(); v != 0 || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, v)
+ }
+ case reflect.Float32, reflect.Float64:
+ if v := rv.Float(); v != 0 || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, v)
+ }
+ case reflect.Complex64, reflect.Complex128:
+ if v := rv.Complex(); v != 0 || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, v)
+ }
+ case reflect.Uintptr:
+ if v := rv.Uint(); v != 0 || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, v)
+ }
+ case reflect.UnsafePointer:
+ s := fmt.Sprintf("%p", rv.Interface())
+ if s == "0x0" && !zero {
+ return
+ }
+
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%s"+suffix, prefix, s)
+ case reflect.Bool:
+ if v := rv.Bool(); v || zero {
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%v"+suffix, prefix, rv.Bool())
+ }
+ case reflect.String:
+ s := rv.Interface().(string)
+ if s == "" && !zero {
+ return
+ }
+
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%q"+suffix, prefix, s)
+ case reflect.Chan:
+ if reflect.Zero(rt).Interface() == rv.Interface() && !zero {
+ return
+ }
+
+ c := rv.Cap()
+ s := ""
+ if c != 0 {
+ s = fmt.Sprintf("// capacity: %d", c)
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%s%s %s%s"+suffix, prefix, rt.ChanDir(), rt.Elem().Name(), s)
+ case reflect.Func:
+ if rv.IsNil() && !zero {
+ return
+ }
+
+ var in, out []string
+ for i := 0; i < rt.NumIn(); i++ {
+ x := reflect.Zero(rt.In(i))
+ in = append(in, fmt.Sprintf("%T", x.Interface()))
+ }
+ if rt.IsVariadic() {
+ i := len(in) - 1
+ in[i] = "..." + in[i][2:]
+ }
+ for i := 0; i < rt.NumOut(); i++ {
+ out = append(out, rt.Out(i).Name())
+ }
+ s := "(" + strings.Join(in, ", ") + ")"
+ t := strings.Join(out, ", ")
+ if len(out) > 1 {
+ t = "(" + t + ")"
+ }
+ if t != "" {
+ t = " " + t
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%sfunc%s%s { ... }"+suffix, prefix, s, t)
+ case reflect.Map:
+ keys := rv.MapKeys()
+ if len(keys) == 0 && !zero {
+ return
+ }
+
+ var buf bytes.Buffer
+ nf := IndentFormatter(&buf, "· ")
+ var skeys []string
+ for i, k := range keys {
+ prettyPrint(protect, nf, "", "", k.Interface(), hooks, false, false)
+ skeys = append(skeys, fmt.Sprintf("%s%10d", buf.Bytes(), i))
+ buf.Reset()
+ }
+ sort.Strings(skeys)
+ sf.Format("%s%T{%i\n", prefix, v)
+ for _, k := range skeys {
+ si := strings.TrimSpace(k[len(k)-10:])
+ k = k[:len(k)-10]
+ n, _ := strconv.ParseUint(si, 10, 64)
+ mv := rv.MapIndex(keys[n])
+ prettyPrint(protect, sf, fmt.Sprintf("%s: ", k), ",\n", mv.Interface(), hooks, false, false)
+ }
+ suffix = strings.Replace(suffix, "%", "%%", -1)
+ sf.Format("%u}" + suffix)
+ }
+}
+
+// Gopath returns the value of the $GOPATH environment variable or its default
+// value if not set.
+func Gopath() string {
+ if r := os.Getenv("GOPATH"); r != "" {
+ return r
+ }
+
+ // go1.8: https://github.com/golang/go/blob/74628a8b9f102bddd5078ee426efe0fd57033115/doc/code.html#L122
+ switch runtime.GOOS {
+ case "plan9":
+ return os.Getenv("home")
+ case "windows":
+ return filepath.Join(os.Getenv("USERPROFILE"), "go")
+ default:
+ return filepath.Join(os.Getenv("HOME"), "go")
+ }
+}
+
+// Homepath returns the user's home directory path.
+func Homepath() string {
+ // go1.8: https://github.com/golang/go/blob/74628a8b9f102bddd5078ee426efe0fd57033115/doc/code.html#L122
+ switch runtime.GOOS {
+ case "plan9":
+ return os.Getenv("home")
+ case "windows":
+ return os.Getenv("USERPROFILE")
+ default:
+ return os.Getenv("HOME")
+ }
+}
+
+// ImportPath returns the import path of the caller or an error, if any.
+func ImportPath() (string, error) {
+ _, file, _, ok := runtime.Caller(1)
+ if !ok {
+ return "", fmt.Errorf("runtime.Caller failed")
+ }
+
+ gopath := Gopath()
+ for _, v := range filepath.SplitList(gopath) {
+ gp := filepath.Join(v, "src")
+ path, err := filepath.Rel(gp, file)
+ if err != nil {
+ continue
+ }
+
+ return filepath.Dir(path), nil
+ }
+
+ return "", fmt.Errorf("cannot determine import path using GOPATH=%s", gopath)
+}