libgo: update to Go1.10beta1

    
    Update the Go library to the 1.10beta1 release.
    
    Requires a few changes to the compiler for modifications to the map
    runtime code, and to handle some nowritebarrier cases in the runtime.
    
    Reviewed-on: https://go-review.googlesource.com/86455

gotools/:
	* Makefile.am (go_cmd_vet_files): New variable.
	(go_cmd_buildid_files, go_cmd_test2json_files): New variables.
	(s-zdefaultcc): Change from constants to functions.
	(noinst_PROGRAMS): Add vet, buildid, and test2json.
	(cgo$(EXEEXT)): Link against $(LIBGOTOOL).
	(vet$(EXEEXT)): New target.
	(buildid$(EXEEXT)): New target.
	(test2json$(EXEEXT)): New target.
	(install-exec-local): Install all $(noinst_PROGRAMS).
	(uninstall-local): Uninstasll all $(noinst_PROGRAMS).
	(check-go-tool): Depend on $(noinst_PROGRAMS).  Copy down
	objabi.go.
	(check-runtime): Depend on $(noinst_PROGRAMS).
	(check-cgo-test, check-carchive-test): Likewise.
	(check-vet): New target.
	(check): Depend on check-vet.  Look at cmd_vet-testlog.
	(.PHONY): Add check-vet.
	* Makefile.in: Rebuild.

From-SVN: r256365

5 files changed, 90 insertions, 26 deletions

diff --git a/libgo/go/fmt/doc.go b/libgo/go/fmt/doc.go
index 014ba06..375cdb4 100644
--- a/libgo/go/fmt/doc.go
+++ b/libgo/go/fmt/doc.go
@@ -47,6 +47,8 @@
 		%X	base 16, upper-case, two characters per byte
 	Pointer:
 		%p	base 16 notation, with leading 0x
+		The %b, %d, %o, %x and %X verbs also work with pointers,
+		formatting the value exactly as if it were an integer.
 
 	The default format for %v is:
 		bool:                    %t
@@ -79,7 +81,8 @@
 	that is, runes. (This differs from C's printf where the
 	units are always measured in bytes.) Either or both of the flags
 	may be replaced with the character '*', causing their values to be
-	obtained from the next operand, which must be of type int.
+	obtained from the next operand (preceding the one to format),
+	which must be of type int.
 
 	For most values, width is the minimum number of runes to output,
 	padding the formatted form with spaces if necessary.
diff --git a/libgo/go/fmt/example_test.go b/libgo/go/fmt/example_test.go
new file mode 100644
index 0000000..aa3cd05
--- /dev/null
+++ b/libgo/go/fmt/example_test.go
@@ -0,0 +1,31 @@
+// Copyright 2017 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.
+
+// +build ignore
+
+package fmt_test
+
+import (
+	"fmt"
+)
+
+// Animal has a Name and an Age to represent an animal.
+type Animal struct {
+	Name string
+	Age  uint
+}
+
+// String makes Animal satisfy the Stringer interface.
+func (a Animal) String() string {
+	return fmt.Sprintf("%v (%d)", a.Name, a.Age)
+}
+
+func ExampleStringer() {
+	a := Animal{
+		Name: "Gopher",
+		Age:  2,
+	}
+	fmt.Println(a)
+	// Output: Gopher (2)
+}
diff --git a/libgo/go/fmt/fmt_test.go b/libgo/go/fmt/fmt_test.go
index 9e6fcfa..b56b84f 100644
--- a/libgo/go/fmt/fmt_test.go
+++ b/libgo/go/fmt/fmt_test.go
@@ -131,6 +131,19 @@ func (byteFormatter) Format(f State, _ rune) {
 
 var byteFormatterSlice = []byteFormatter{'h', 'e', 'l', 'l', 'o'}
 
+// Copy of io.stringWriter interface used by writeStringFormatter for type assertion.
+type stringWriter interface {
+	WriteString(s string) (n int, err error)
+}
+
+type writeStringFormatter string
+
+func (sf writeStringFormatter) Format(f State, c rune) {
+	if sw, ok := f.(stringWriter); ok {
+		sw.WriteString("***" + string(sf) + "***")
+	}
+}
+
 var fmtTests = []struct {
 	fmt string
 	val interface{}
@@ -977,6 +990,11 @@ var fmtTests = []struct {
 	// This next case seems wrong, but the docs say the Formatter wins here.
 	{"%#v", byteFormatterSlice, "[]fmt_test.byteFormatter{X, X, X, X, X}"},
 
+	// pp.WriteString
+	{"%s", writeStringFormatter(""), "******"},
+	{"%s", writeStringFormatter("xyz"), "***xyz***"},
+	{"%s", writeStringFormatter("⌘/⌘"), "***⌘/⌘***"},
+
 	// reflect.Value handled specially in Go 1.5, making it possible to
 	// see inside non-exported fields (which cannot be accessed with Interface()).
 	// Issue 8965.
@@ -1201,6 +1219,14 @@ func BenchmarkSprintfTruncateString(b *testing.B) {
 	})
 }
 
+func BenchmarkSprintfSlowParsingPath(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			Sprintf("%.v", nil)
+		}
+	})
+}
+
 func BenchmarkSprintfQuoteString(b *testing.B) {
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
@@ -1709,12 +1735,14 @@ func TestIsSpace(t *testing.T) {
 	}
 }
 
+func hideFromVet(s string) string { return s }
+
 func TestNilDoesNotBecomeTyped(t *testing.T) {
 	type A struct{}
 	type B struct{}
 	var a *A = nil
 	var b B = B{}
-	got := Sprintf("%s %s %s %s %s", nil, a, nil, b, nil) // go vet should complain about this line.
+	got := Sprintf(hideFromVet("%s %s %s %s %s"), nil, a, nil, b, nil)
 	const expect = "%!s(<nil>) %!s(*fmt_test.A=<nil>) %!s(<nil>) {} %!s(<nil>)"
 	if got != expect {
 		t.Errorf("expected:\n\t%q\ngot:\n\t%q", expect, got)
diff --git a/libgo/go/fmt/print.go b/libgo/go/fmt/print.go
index 2bd88f9..98c156a 100644
--- a/libgo/go/fmt/print.go
+++ b/libgo/go/fmt/print.go
@@ -172,6 +172,13 @@ func (p *pp) Write(b []byte) (ret int, err error) {
 	return len(b), nil
 }
 
+// Implement WriteString so that we can call io.WriteString
+// on a pp (through state), for efficiency.
+func (p *pp) WriteString(s string) (ret int, err error) {
+	p.buf.WriteString(s)
+	return len(s), nil
+}
+
 // These routines end in 'f' and take a format string.
 
 // Fprintf formats according to a format specifier and writes to w.
@@ -837,7 +844,7 @@ func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
 			p.buf.WriteByte(']')
 		}
 	case reflect.Ptr:
-		// pointer to array or slice or struct?  ok at top level
+		// pointer to array or slice or struct? ok at top level
 		// but not embedded (avoid loops)
 		if depth == 0 && f.Pointer() != 0 {
 			switch a := f.Elem(); a.Kind() {
@@ -1067,8 +1074,11 @@ formatLoop:
 			break
 		}
 
-		verb, w := utf8.DecodeRuneInString(format[i:])
-		i += w
+		verb, size := rune(format[i]), 1
+		if verb >= utf8.RuneSelf {
+			verb, size = utf8.DecodeRuneInString(format[i:])
+		}
+		i += size
 
 		switch {
 		case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec.
diff --git a/libgo/go/fmt/scan.go b/libgo/go/fmt/scan.go
index cd7232c..ae79e39 100644
--- a/libgo/go/fmt/scan.go
+++ b/libgo/go/fmt/scan.go
@@ -298,13 +298,6 @@ func notSpace(r rune) bool {
 	return !isSpace(r)
 }
 
-// SkipSpace provides Scan methods the ability to skip space and newline
-// characters in keeping with the current scanning mode set by format strings
-// and Scan/Scanln.
-func (s *ss) SkipSpace() {
-	s.skipSpace(false)
-}
-
 // readRune is a structure to enable reading UTF-8 encoded code points
 // from an io.Reader. It is used if the Reader given to the scanner does
 // not already implement io.RuneScanner.
@@ -421,8 +414,10 @@ func (s *ss) free(old ssave) {
 	ssFree.Put(s)
 }
 
-// skipSpace skips spaces and maybe newlines.
-func (s *ss) skipSpace(stopAtNewline bool) {
+// SkipSpace provides Scan methods the ability to skip space and newline
+// characters in keeping with the current scanning mode set by format strings
+// and Scan/Scanln.
+func (s *ss) SkipSpace() {
 	for {
 		r := s.getRune()
 		if r == eof {
@@ -432,9 +427,6 @@ func (s *ss) skipSpace(stopAtNewline bool) {
 			continue
 		}
 		if r == '\n' {
-			if stopAtNewline {
-				break
-			}
 			if s.nlIsSpace {
 				continue
 			}
@@ -453,7 +445,7 @@ func (s *ss) skipSpace(stopAtNewline bool) {
 // newlines are treated as spaces.
 func (s *ss) token(skipSpace bool, f func(rune) bool) []byte {
 	if skipSpace {
-		s.skipSpace(false)
+		s.SkipSpace()
 	}
 	// read until white space or newline
 	for {
@@ -537,7 +529,7 @@ func (s *ss) okVerb(verb rune, okVerbs, typ string) bool {
 
 // scanBool returns the value of the boolean represented by the next token.
 func (s *ss) scanBool(verb rune) bool {
-	s.skipSpace(false)
+	s.SkipSpace()
 	s.notEOF()
 	if !s.okVerb(verb, "tv", "boolean") {
 		return false
@@ -641,7 +633,7 @@ func (s *ss) scanInt(verb rune, bitSize int) int64 {
 	if verb == 'c' {
 		return s.scanRune(bitSize)
 	}
-	s.skipSpace(false)
+	s.SkipSpace()
 	s.notEOF()
 	base, digits := s.getBase(verb)
 	haveDigits := false
@@ -674,7 +666,7 @@ func (s *ss) scanUint(verb rune, bitSize int) uint64 {
 	if verb == 'c' {
 		return uint64(s.scanRune(bitSize))
 	}
-	s.skipSpace(false)
+	s.SkipSpace()
 	s.notEOF()
 	base, digits := s.getBase(verb)
 	haveDigits := false
@@ -795,7 +787,7 @@ func (s *ss) scanComplex(verb rune, n int) complex128 {
 	if !s.okVerb(verb, floatVerbs, "complex") {
 		return 0
 	}
-	s.skipSpace(false)
+	s.SkipSpace()
 	s.notEOF()
 	sreal, simag := s.complexTokens()
 	real := s.convertFloat(sreal, n/2)
@@ -809,7 +801,7 @@ func (s *ss) convertString(verb rune) (str string) {
 	if !s.okVerb(verb, "svqxX", "string") {
 		return ""
 	}
-	s.skipSpace(false)
+	s.SkipSpace()
 	s.notEOF()
 	switch verb {
 	case 'q':
@@ -973,13 +965,13 @@ func (s *ss) scanOne(verb rune, arg interface{}) {
 	// scan in high precision and convert, in order to preserve the correct error condition.
 	case *float32:
 		if s.okVerb(verb, floatVerbs, "float32") {
-			s.skipSpace(false)
+			s.SkipSpace()
 			s.notEOF()
 			*v = float32(s.convertFloat(s.floatToken(), 32))
 		}
 	case *float64:
 		if s.okVerb(verb, floatVerbs, "float64") {
-			s.skipSpace(false)
+			s.SkipSpace()
 			s.notEOF()
 			*v = s.convertFloat(s.floatToken(), 64)
 		}
@@ -1017,7 +1009,7 @@ func (s *ss) scanOne(verb rune, arg interface{}) {
 				v.Index(i).SetUint(uint64(str[i]))
 			}
 		case reflect.Float32, reflect.Float64:
-			s.skipSpace(false)
+			s.SkipSpace()
 			s.notEOF()
 			v.SetFloat(s.convertFloat(s.floatToken(), v.Type().Bits()))
 		case reflect.Complex64, reflect.Complex128: