idna: Revert "use code generated by internal x/text package"

This reverts commit 67957fd0.

Updates golang/go#18567

Change-Id: I4a9da509eb95949d2e3ab08763274abf6706f6f8
Reviewed-on: https://go-review.googlesource.com/35270
Run-TryBot: Nigel Tao <nigeltao@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Benoit Sigoure <tsunanet@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

idna/idna_test.go

@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// This file contains a few basic functional tests.
-// Full tests are done in x/text/internal/export/idna.
-
 package idna
 
 import (
@@ -41,3 +38,6 @@ func TestIDNA(t *testing.T) {
 		}
 	}
 }
+
+// TODO(nigeltao): test errors, once we've specified when ToASCII and ToUnicode
+// return errors.

idna/punycode.go

-// Copied from the golang.org/x/text repo; DO NOT EDIT
-
-// Copyright 2016 The Go Authors. All rights reserved.
+// Copyright 2012 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.
 
@@ -9,6 +7,7 @@ package idna
 // This file implements the Punycode algorithm from RFC 3492.
 
 import (
+	"fmt"
 	"math"
 	"strings"
 	"unicode/utf8"
@@ -28,8 +27,6 @@ const (
 	tmin        int32 = 1
 )
 
-func punyError(s string) error { return &labelError{s, "A3"} }
-
 // decode decodes a string as specified in section 6.2.
 func decode(encoded string) (string, error) {
 	if encoded == "" {
@@ -37,7 +34,7 @@ func decode(encoded string) (string, error) {
 	}
 	pos := 1 + strings.LastIndex(encoded, "-")
 	if pos == 1 {
-		return "", punyError(encoded)
+		return "", fmt.Errorf("idna: invalid label %q", encoded)
 	}
 	if pos == len(encoded) {
 		return encoded[:len(encoded)-1], nil
@@ -53,16 +50,16 @@ func decode(encoded string) (string, error) {
 		oldI, w := i, int32(1)
 		for k := base; ; k += base {
 			if pos == len(encoded) {
-				return "", punyError(encoded)
+				return "", fmt.Errorf("idna: invalid label %q", encoded)
 			}
 			digit, ok := decodeDigit(encoded[pos])
 			if !ok {
-				return "", punyError(encoded)
+				return "", fmt.Errorf("idna: invalid label %q", encoded)
 			}
 			pos++
 			i += digit * w
 			if i < 0 {
-				return "", punyError(encoded)
+				return "", fmt.Errorf("idna: invalid label %q", encoded)
 			}
 			t := k - bias
 			if t < tmin {
@@ -75,7 +72,7 @@ func decode(encoded string) (string, error) {
 			}
 			w *= base - t
 			if w >= math.MaxInt32/base {
-				return "", punyError(encoded)
+				return "", fmt.Errorf("idna: invalid label %q", encoded)
 			}
 		}
 		x := int32(len(output) + 1)
@@ -83,7 +80,7 @@ func decode(encoded string) (string, error) {
 		n += i / x
 		i %= x
 		if n > utf8.MaxRune || len(output) >= 1024 {
-			return "", punyError(encoded)
+			return "", fmt.Errorf("idna: invalid label %q", encoded)
 		}
 		output = append(output, 0)
 		copy(output[i+1:], output[i:])
@@ -124,14 +121,14 @@ func encode(prefix, s string) (string, error) {
 		}
 		delta += (m - n) * (h + 1)
 		if delta < 0 {
-			return "", punyError(s)
+			return "", fmt.Errorf("idna: invalid label %q", s)
 		}
 		n = m
 		for _, r := range s {
 			if r < n {
 				delta++
 				if delta < 0 {
-					return "", punyError(s)
+					return "", fmt.Errorf("idna: invalid label %q", s)
 				}
 				continue
 			}

idna/punycode_test.go

+// Copyright 2012 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 idna
+
+import (
+	"strings"
+	"testing"
+)
+
+var punycodeTestCases = [...]struct {
+	s, encoded string
+}{
+	{"", ""},
+	{"-", "--"},
+	{"-a", "-a-"},
+	{"-a-", "-a--"},
+	{"a", "a-"},
+	{"a-", "a--"},
+	{"a-b", "a-b-"},
+	{"books", "books-"},
+	{"bücher", "bcher-kva"},
+	{"Hello世界", "Hello-ck1hg65u"},
+	{"ü", "tda"},
+	{"üý", "tdac"},
+
+	// The test cases below come from RFC 3492 section 7.1 with Errata 3026.
+	{
+		// (A) Arabic (Egyptian).
+		"\u0644\u064A\u0647\u0645\u0627\u0628\u062A\u0643\u0644" +
+			"\u0645\u0648\u0634\u0639\u0631\u0628\u064A\u061F",
+		"egbpdaj6bu4bxfgehfvwxn",
+	},
+	{
+		// (B) Chinese (simplified).
+		"\u4ED6\u4EEC\u4E3A\u4EC0\u4E48\u4E0D\u8BF4\u4E2D\u6587",
+		"ihqwcrb4cv8a8dqg056pqjye",
+	},
+	{
+		// (C) Chinese (traditional).
+		"\u4ED6\u5011\u7232\u4EC0\u9EBD\u4E0D\u8AAA\u4E2D\u6587",
+		"ihqwctvzc91f659drss3x8bo0yb",
+	},
+	{
+		// (D) Czech.
+		"\u0050\u0072\u006F\u010D\u0070\u0072\u006F\u0073\u0074" +
+			"\u011B\u006E\u0065\u006D\u006C\u0075\u0076\u00ED\u010D" +
+			"\u0065\u0073\u006B\u0079",
+		"Proprostnemluvesky-uyb24dma41a",
+	},
+	{
+		// (E) Hebrew.
+		"\u05DC\u05DE\u05D4\u05D4\u05DD\u05E4\u05E9\u05D5\u05D8" +
+			"\u05DC\u05D0\u05DE\u05D3\u05D1\u05E8\u05D9\u05DD\u05E2" +
+			"\u05D1\u05E8\u05D9\u05EA",
+		"4dbcagdahymbxekheh6e0a7fei0b",
+	},
+	{
+		// (F) Hindi (Devanagari).
+		"\u092F\u0939\u0932\u094B\u0917\u0939\u093F\u0928\u094D" +
+			"\u0926\u0940\u0915\u094D\u092F\u094B\u0902\u0928\u0939" +
+			"\u0940\u0902\u092C\u094B\u0932\u0938\u0915\u0924\u0947" +
+			"\u0939\u0948\u0902",
+		"i1baa7eci9glrd9b2ae1bj0hfcgg6iyaf8o0a1dig0cd",
+	},
+	{
+		// (G) Japanese (kanji and hiragana).
+		"\u306A\u305C\u307F\u3093\u306A\u65E5\u672C\u8A9E\u3092" +
+			"\u8A71\u3057\u3066\u304F\u308C\u306A\u3044\u306E\u304B",
+		"n8jok5ay5dzabd5bym9f0cm5685rrjetr6pdxa",
+	},
+	{
+		// (H) Korean (Hangul syllables).
+		"\uC138\uACC4\uC758\uBAA8\uB4E0\uC0AC\uB78C\uB4E4\uC774" +
+			"\uD55C\uAD6D\uC5B4\uB97C\uC774\uD574\uD55C\uB2E4\uBA74" +
+			"\uC5BC\uB9C8\uB098\uC88B\uC744\uAE4C",
+		"989aomsvi5e83db1d2a355cv1e0vak1dwrv93d5xbh15a0dt30a5j" +
+			"psd879ccm6fea98c",
+	},
+	{
+		// (I) Russian (Cyrillic).
+		"\u043F\u043E\u0447\u0435\u043C\u0443\u0436\u0435\u043E" +
+			"\u043D\u0438\u043D\u0435\u0433\u043E\u0432\u043E\u0440" +
+			"\u044F\u0442\u043F\u043E\u0440\u0443\u0441\u0441\u043A" +
+			"\u0438",
+		"b1abfaaepdrnnbgefbadotcwatmq2g4l",
+	},
+	{
+		// (J) Spanish.
+		"\u0050\u006F\u0072\u0071\u0075\u00E9\u006E\u006F\u0070" +
+			"\u0075\u0065\u0064\u0065\u006E\u0073\u0069\u006D\u0070" +
+			"\u006C\u0065\u006D\u0065\u006E\u0074\u0065\u0068\u0061" +
+			"\u0062\u006C\u0061\u0072\u0065\u006E\u0045\u0073\u0070" +
+			"\u0061\u00F1\u006F\u006C",
+		"PorqunopuedensimplementehablarenEspaol-fmd56a",
+	},
+	{
+		// (K) Vietnamese.
+		"\u0054\u1EA1\u0069\u0073\u0061\u006F\u0068\u1ECD\u006B" +
+			"\u0068\u00F4\u006E\u0067\u0074\u0068\u1EC3\u0063\u0068" +
+			"\u1EC9\u006E\u00F3\u0069\u0074\u0069\u1EBF\u006E\u0067" +
+			"\u0056\u0069\u1EC7\u0074",
+		"TisaohkhngthchnitingVit-kjcr8268qyxafd2f1b9g",
+	},
+	{
+		// (L) 3<nen>B<gumi><kinpachi><sensei>.
+		"\u0033\u5E74\u0042\u7D44\u91D1\u516B\u5148\u751F",
+		"3B-ww4c5e180e575a65lsy2b",
+	},
+	{
+		// (M) <amuro><namie>-with-SUPER-MONKEYS.
+		"\u5B89\u5BA4\u5948\u7F8E\u6075\u002D\u0077\u0069\u0074" +
+			"\u0068\u002D\u0053\u0055\u0050\u0045\u0052\u002D\u004D" +
+			"\u004F\u004E\u004B\u0045\u0059\u0053",
+		"-with-SUPER-MONKEYS-pc58ag80a8qai00g7n9n",
+	},
+	{
+		// (N) Hello-Another-Way-<sorezore><no><basho>.
+		"\u0048\u0065\u006C\u006C\u006F\u002D\u0041\u006E\u006F" +
+			"\u0074\u0068\u0065\u0072\u002D\u0057\u0061\u0079\u002D" +
+			"\u305D\u308C\u305E\u308C\u306E\u5834\u6240",
+		"Hello-Another-Way--fc4qua05auwb3674vfr0b",
+	},
+	{
+		// (O) <hitotsu><yane><no><shita>2.
+		"\u3072\u3068\u3064\u5C4B\u6839\u306E\u4E0B\u0032",
+		"2-u9tlzr9756bt3uc0v",
+	},
+	{
+		// (P) Maji<de>Koi<suru>5<byou><mae>
+		"\u004D\u0061\u006A\u0069\u3067\u004B\u006F\u0069\u3059" +
+			"\u308B\u0035\u79D2\u524D",
+		"MajiKoi5-783gue6qz075azm5e",
+	},
+	{
+		// (Q) <pafii>de<runba>
+		"\u30D1\u30D5\u30A3\u30FC\u0064\u0065\u30EB\u30F3\u30D0",
+		"de-jg4avhby1noc0d",
+	},
+	{
+		// (R) <sono><supiido><de>
+		"\u305D\u306E\u30B9\u30D4\u30FC\u30C9\u3067",
+		"d9juau41awczczp",
+	},
+	{
+		// (S) -> $1.00 <-
+		"\u002D\u003E\u0020\u0024\u0031\u002E\u0030\u0030\u0020" +
+			"\u003C\u002D",
+		"-> $1.00 <--",
+	},
+}
+
+func TestPunycode(t *testing.T) {
+	for _, tc := range punycodeTestCases {
+		if got, err := decode(tc.encoded); err != nil {
+			t.Errorf("decode(%q): %v", tc.encoded, err)
+		} else if got != tc.s {
+			t.Errorf("decode(%q): got %q, want %q", tc.encoded, got, tc.s)
+		}
+
+		if got, err := encode("", tc.s); err != nil {
+			t.Errorf(`encode("", %q): %v`, tc.s, err)
+		} else if got != tc.encoded {
+			t.Errorf(`encode("", %q): got %q, want %q`, tc.s, got, tc.encoded)
+		}
+	}
+}
+
+var punycodeErrorTestCases = [...]string{
+	"decode -",            // A sole '-' is invalid.
+	"decode foo\x00bar",   // '\x00' is not in [0-9A-Za-z].
+	"decode foo#bar",      // '#' is not in [0-9A-Za-z].
+	"decode foo\u00A3bar", // '\u00A3' is not in [0-9A-Za-z].
+	"decode 9",            // "9a" decodes to codepoint \u00A3; "9" is truncated.
+	"decode 99999a",       // "99999a" decodes to codepoint \U0048A3C1, which is > \U0010FFFF.
+	"decode 9999999999a",  // "9999999999a" overflows the int32 calculation.
+
+	"encode " + strings.Repeat("x", 65536) + "\uff00", // int32 overflow.
+}
+
+func TestPunycodeErrors(t *testing.T) {
+	for _, tc := range punycodeErrorTestCases {
+		var err error
+		switch {
+		case strings.HasPrefix(tc, "decode "):
+			_, err = decode(tc[7:])
+		case strings.HasPrefix(tc, "encode "):
+			_, err = encode("", tc[7:])
+		}
+		if err == nil {
+			if len(tc) > 256 {
+				tc = tc[:100] + "..." + tc[len(tc)-100:]
+			}
+			t.Errorf("no error for %s", tc)
+		}
+	}
+}

idna/trie.go

-// Copied from the golang.org/x/text repo; DO NOT EDIT
-
-// Copyright 2016 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 idna
-
-// appendMapping appends the mapping for the respective rune. isMapped must be
-// true. A mapping is a categorization of a rune as defined in UTS #46.
-func (c info) appendMapping(b []byte, s string) []byte {
-	index := int(c >> indexShift)
-	if c&xorBit == 0 {
-		s := mappings[index:]
-		return append(b, s[1:s[0]+1]...)
-	}
-	b = append(b, s...)
-	if c&inlineXOR == inlineXOR {
-		// TODO: support and handle two-byte inline masks
-		b[len(b)-1] ^= byte(index)
-	} else {
-		for p := len(b) - int(xorData[index]); p < len(b); p++ {
-			index++
-			b[p] ^= xorData[index]
-		}
-	}
-	return b
-}
-
-// Sparse block handling code.
-
-type valueRange struct {
-	value  uint16 // header: value:stride
-	lo, hi byte   // header: lo:n
-}
-
-type sparseBlocks struct {
-	values []valueRange
-	offset []uint16
-}
-
-var idnaSparse = sparseBlocks{
-	values: idnaSparseValues[:],
-	offset: idnaSparseOffset[:],
-}
-
-var trie = newIdnaTrie(0)
-
-// lookup determines the type of block n and looks up the value for b.
-// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block
-// is a list of ranges with an accompanying value. Given a matching range r,
-// the value for b is by r.value + (b - r.lo) * stride.
-func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
-	offset := t.offset[n]
-	header := t.values[offset]
-	lo := offset + 1
-	hi := lo + uint16(header.lo)
-	for lo < hi {
-		m := lo + (hi-lo)/2
-		r := t.values[m]
-		if r.lo <= b && b <= r.hi {
-			return r.value + uint16(b-r.lo)*header.value
-		}
-		if b < r.lo {
-			hi = m
-		} else {
-			lo = m + 1
-		}
-	}
-	return 0
-}

idna/trieval.go

-// Copied from the golang.org/x/text repo; DO NOT EDIT
-
-// This file was generated by go generate; DO NOT EDIT
-
-package idna
-
-// This file contains definitions for interpreting the trie value of the idna
-// trie generated by "go run gen*.go". It is shared by both the generator
-// program and the resultant package. Sharing is achieved by the generator
-// copying gen_trieval.go to trieval.go and changing what's above this comment.
-
-// info holds information from the IDNA mapping table for a single rune. It is
-// the value returned by a trie lookup. In most cases, all information fits in
-// a 16-bit value. For mappings, this value may contain an index into a slice
-// with the mapped string. Such mappings can consist of the actual mapped value
-// or an XOR pattern to be applied to the bytes of the UTF8 encoding of the
-// input rune. This technique is used by the cases packages and reduces the
-// table size significantly.
-//
-// The per-rune values have the following format:
-//
-//   if mapped {
-//     if inlinedXOR {
-//       15..13 inline XOR marker
-//       12..11 unused
-//       10..3  inline XOR mask
-//     } else {
-//       15..3  index into xor or mapping table
-//     }
-//   } else {
-//       15..13 unused
-//           12 modifier (including virama)
-//           11 virama modifier
-//       10..8  joining type
-//        7..3  category type
-//   }
-//      2  use xor pattern
-//   1..0  mapped category
-//
-// See the definitions below for a more detailed description of the various
-// bits.
-type info uint16
-
-const (
-	catSmallMask = 0x3
-	catBigMask   = 0xF8
-	indexShift   = 3
-	xorBit       = 0x4    // interpret the index as an xor pattern
-	inlineXOR    = 0xE000 // These bits are set if the XOR pattern is inlined.
-
-	joinShift = 8
-	joinMask  = 0x07
-
-	viramaModifier = 0x0800
-	modifier       = 0x1000
-)
-
-// A category corresponds to a category defined in the IDNA mapping table.
-type category uint16
-
-const (
-	unknown              category = 0 // not defined currently in unicode.
-	mapped               category = 1
-	disallowedSTD3Mapped category = 2
-	deviation            category = 3
-)
-
-const (
-	valid               category = 0x08
-	validNV8            category = 0x18
-	validXV8            category = 0x28
-	disallowed          category = 0x40
-	disallowedSTD3Valid category = 0x80
-	ignored             category = 0xC0
-)
-
-// join types and additional rune information
-const (
-	joiningL = (iota + 1)
-	joiningD
-	joiningT
-	joiningR
-
-	//the following types are derived during processing
-	joinZWJ
-	joinZWNJ
-	joinVirama
-	numJoinTypes
-)
-
-func (c info) isMapped() bool {
-	return c&0x3 != 0
-}
-
-func (c info) category() category {
-	small := c & catSmallMask
-	if small != 0 {
-		return category(small)
-	}
-	return category(c & catBigMask)
-}
-
-func (c info) joinType() info {
-	if c.isMapped() {
-		return 0
-	}
-	return (c >> joinShift) & joinMask
-}
-
-func (c info) isModifier() bool {
-	return c&(modifier|catSmallMask) == modifier
-}
-
-func (c info) isViramaModifier() bool {
-	return c&(viramaModifier|catSmallMask) == viramaModifier
-}