[dev.inline] cmd/compile/internal/syntax: remove gcCompat uses in scanner

- make the scanner unconditionally gc compatible
- consistently use "invalid" instead "illegal" in errors

Reviewed in and cherry-picked from https://go-review.googlesource.com/#/c/33896/.

Change-Id: I4c4253e7392f3311b0d838bbe503576c9469b203
Reviewed-on: https://go-review.googlesource.com/34237
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

diff --git a/src/cmd/compile/internal/syntax/parser.go b/src/cmd/compile/internal/syntax/parser.go
index 505031ac2bad7a3c5554f97ad8e8e9fa84af8cc3..a58513478b081d4ec12ff779e3b401623e66e97a 100644 (file)
--- a/src/cmd/compile/internal/syntax/parser.go
+++ b/src/cmd/compile/internal/syntax/parser.go
@@ -53,7 +53,6 @@ func (p *parser) init(filename string, src io.Reader, errh ErrorHandler, pragh P
                                p.pragma |= pragh(p.pos_at(line, col), text)
                        }
                },
-               gcCompat,
        )
 
        p.first = nil

diff --git a/src/cmd/compile/internal/syntax/scanner.go b/src/cmd/compile/internal/syntax/scanner.go
index 8af2f1ce14d1b39007ec6a1a126ea4e3150574ab..149827b21c683b43ce3bc3665e79e83d050d1454 100644 (file)
--- a/src/cmd/compile/internal/syntax/scanner.go
+++ b/src/cmd/compile/internal/syntax/scanner.go
@@ -21,9 +21,8 @@ import (
 
 type scanner struct {
        source
-       pragh    func(line, col uint, msg string)
-       gcCompat bool // TODO(gri) remove this eventually (only here so we can build w/o parser)
-       nlsemi   bool // if set '\n' and EOF translate to ';'
+       pragh  func(line, col uint, msg string)
+       nlsemi bool // if set '\n' and EOF translate to ';'
 
        // current token, valid after calling next()
        line, col uint
@@ -34,10 +33,9 @@ type scanner struct {
        prec      int      // valid if tok is _Operator, _AssignOp, or _IncOp
 }
 
-func (s *scanner) init(src io.Reader, errh, pragh func(line, col uint, msg string), gcCompat bool) {
+func (s *scanner) init(src io.Reader, errh, pragh func(line, col uint, msg string)) {
        s.source.init(src, errh)
        s.pragh = pragh
-       s.gcCompat = gcCompat
        s.nlsemi = false
 }
 
@@ -67,7 +65,7 @@ redo:
        // token start
        s.line, s.col = s.source.line0, s.source.col0
 
-       if isLetter(c) || c >= utf8.RuneSelf && (unicode.IsLetter(c) || s.isCompatRune(c, true)) {
+       if isLetter(c) || c >= utf8.RuneSelf && s.isIdentRune(c, true) {
                s.ident()
                return
        }
@@ -290,7 +288,7 @@ redo:
 
        default:
                s.tok = 0
-               s.error(fmt.Sprintf("illegal character %#U", c))
+               s.error(fmt.Sprintf("invalid character %#U", c))
                goto redo
        }
 
@@ -324,7 +322,7 @@ func (s *scanner) ident() {
 
        // general case
        if c >= utf8.RuneSelf {
-               for unicode.IsLetter(c) || c == '_' || unicode.IsDigit(c) || s.isCompatRune(c, false) {
+               for s.isIdentRune(c, false) {
                        c = s.getr()
                }
        }
@@ -346,14 +344,18 @@ func (s *scanner) ident() {
        s.tok = _Name
 }
 
-func (s *scanner) isCompatRune(c rune, start bool) bool {
-       if !s.gcCompat || c < utf8.RuneSelf {
-               return false
-       }
-       if start && unicode.IsNumber(c) {
-               s.error(fmt.Sprintf("identifier cannot begin with digit %#U", c))
-       } else {
+func (s *scanner) isIdentRune(c rune, first bool) bool {
+       switch {
+       case unicode.IsLetter(c) || c == '_':
+               // ok
+       case unicode.IsDigit(c):
+               if first {
+                       s.error(fmt.Sprintf("identifier cannot begin with digit %#U", c))
+               }
+       case c >= utf8.RuneSelf:
                s.error(fmt.Sprintf("invalid identifier character %#U", c))
+       default:
+               return false
        }
        return true
 }
@@ -643,19 +645,11 @@ func (s *scanner) escape(quote rune) bool {
                        if c < 0 {
                                return true // complain in caller about EOF
                        }
-                       if s.gcCompat {
-                               name := "hex"
-                               if base == 8 {
-                                       name = "octal"
-                               }
-                               s.error(fmt.Sprintf("non-%s character in escape sequence: %c", name, c))
-                       } else {
-                               if c != quote {
-                                       s.error(fmt.Sprintf("illegal character %#U in escape sequence", c))
-                               } else {
-                                       s.error("escape sequence incomplete")
-                               }
+                       kind := "hex"
+                       if base == 8 {
+                               kind = "octal"
                        }
+                       s.error(fmt.Sprintf("non-%s character in escape sequence: %c", kind, c))
                        s.ungetr()
                        return false
                }

diff --git a/src/cmd/compile/internal/syntax/scanner_test.go b/src/cmd/compile/internal/syntax/scanner_test.go
index 988a74c2875f1e037e133209512f701cb4cbdf84..5532780399c4e6c0eb9185abaccac1643d101e23 100644 (file)
--- a/src/cmd/compile/internal/syntax/scanner_test.go
+++ b/src/cmd/compile/internal/syntax/scanner_test.go
@@ -22,7 +22,7 @@ func TestScanner(t *testing.T) {
        defer src.Close()
 
        var s scanner
-       s.init(src, nil, nil, false)
+       s.init(src, nil, nil)
        for {
                s.next()
                if s.tok == _EOF {
@@ -51,7 +51,7 @@ func TestTokens(t *testing.T) {
 
        // scan source
        var got scanner
-       got.init(&bytesReader{buf}, nil, nil, false)
+       got.init(&bytesReader{buf}, nil, nil)
        got.next()
        for i, want := range sampleTokens {
                nlsemi := false
@@ -269,7 +269,7 @@ func TestScanErrors(t *testing.T) {
 
                // token-level errors
                {"x + ~y", "bitwise complement operator is ^", 1, 5},
-               {"foo$bar = 0", "illegal character U+0024 '$'", 1, 4},
+               {"foo$bar = 0", "invalid character U+0024 '$'", 1, 4},
                {"const x = 0xyz", "malformed hex constant", 1, 13},
                {"0123456789", "malformed octal constant", 1, 11},
                {"0123456789. /* foobar", "comment not terminated", 1, 13},   // valid float constant
@@ -348,7 +348,7 @@ func TestScanErrors(t *testing.T) {
                                // TODO(gri) make this use position info
                                t.Errorf("%q: got unexpected %q at line = %d", test.src, msg, line)
                        }
-               }, nil, true)
+               }, nil)
 
                for {
                        s.next()

diff --git a/test/fixedbugs/issue11610.go b/test/fixedbugs/issue11610.go
index 5e77932362dcd4e2779a5afac6efcd77a8f4a743..8ca31bf394b84dcab42fcd17912542c179359eca 100644 (file)
--- a/test/fixedbugs/issue11610.go
+++ b/test/fixedbugs/issue11610.go
@@ -9,7 +9,7 @@
 
 package a
 import""  // ERROR "import path is empty"
-var?      // ERROR "illegal character U\+003F '\?'"
+var?      // ERROR "invalid character U\+003F '\?'"
 
 var x int // ERROR "unexpected var"