cue/scanner: drop support for //line comments

This was inherited from Go, but it was never used nor wired up. We leave all the machinery in cue/token to support adjusted positions, as we may wish to later support adjusted positions via CUE attributes. Signed-off-by: Daniel Martí <[email protected]> Change-Id: I1485c07c287f8790d09df3e894aa8fe301e7dfd2 Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1206373 Reviewed-by: Marcel van Lohuizen <[email protected]> TryBot-Result: CUEcueckoo <[email protected]> Unity-Result: CUE porcuepine <[email protected]>
cue-lang · Dec 27, 2024 · 901604a · 901604a
1 parent ae8ee75
commit 901604a
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diff --git a/cue/scanner/scanner.go b/cue/scanner/scanner.go
@@ -18,10 +18,8 @@
 package scanner
 
 import (
-	"bytes"
 	"fmt"
 	"path/filepath"
-	"strconv"
 	"unicode"
 	"unicode/utf8"
 
@@ -48,7 +46,6 @@ type Scanner struct {
 	ch              rune // current character
 	offset          int  // character offset
 	rdOffset        int  // reading offset (position after current character)
-	lineOffset      int  // current line offset
 	linesSinceLast  int
 	spacesSinceLast int
 	insertEOL       bool // insert a comma before next newline
@@ -73,7 +70,6 @@ func (s *Scanner) next() {
 	if s.rdOffset < len(s.src) {
 		s.offset = s.rdOffset
 		if s.ch == '\n' {
-			s.lineOffset = s.offset
 			s.file.AddLine(s.offset)
 		}
 		r, w := rune(s.src[s.rdOffset]), 1
@@ -94,7 +90,6 @@ func (s *Scanner) next() {
 	} else {
 		s.offset = len(s.src)
 		if s.ch == '\n' {
-			s.lineOffset = s.offset
 			s.file.AddLine(s.offset)
 		}
 		s.ch = -1 // eof
@@ -139,7 +134,6 @@ func (s *Scanner) Init(file *token.File, src []byte, eh ErrorHandler, mode Mode)
 	s.ch = ' '
 	s.offset = 0
 	s.rdOffset = 0
-	s.lineOffset = 0
 	s.insertEOL = false
 	s.ErrorCount = 0
 
@@ -156,29 +150,6 @@ func (s *Scanner) errf(offs int, msg string, args ...interface{}) {
 	s.ErrorCount++
 }
 
-var prefix = []byte("//line ")
-
-func (s *Scanner) interpretLineComment(text []byte) {
-	if bytes.HasPrefix(text, prefix) {
-		// get filename and line number, if any
-		if i := bytes.LastIndex(text, []byte{':'}); i > 0 {
-			if line, err := strconv.Atoi(string(text[i+1:])); err == nil && line > 0 {
-				// valid //line filename:line comment
-				filename := string(bytes.TrimSpace(text[len(prefix):i]))
-				if filename != "" {
-					filename = filepath.Clean(filename)
-					if !filepath.IsAbs(filename) {
-						// make filename relative to current directory
-						filename = filepath.Join(s.dir, filename)
-					}
-				}
-				// update scanner position
-				s.file.AddLineInfo(s.lineOffset+len(text)+1, filename, line) // +len(text)+1 since comment applies to next line
-			}
-		}
-	}
-}
-
 func (s *Scanner) scanComment() string {
 	// initial '/' already consumed; s.ch == '/'
 	offs := s.offset - 1 // position of initial '/'
@@ -193,10 +164,6 @@ func (s *Scanner) scanComment() string {
 			}
 			s.next()
 		}
-		if offs == s.lineOffset {
-			// comment starts at the beginning of the current line
-			s.interpretLineComment(s.src[offs:s.offset])
-		}
 		goto exit
 	}
 

diff --git a/cue/scanner/scanner_test.go b/cue/scanner/scanner_test.go
@@ -17,8 +17,6 @@ package scanner
 import (
 	"fmt"
 	"os"
-	"path/filepath"
-	"runtime"
 	"strings"
 	"testing"
 
@@ -509,73 +507,6 @@ func TestRelative(t *testing.T) {
 	}
 }
 
-type segment struct {
-	srcline  string // a line of source text
-	filename string // filename for current token
-	line     int    // line number for current token
-}
-
-var segments = []segment{
-	// exactly one token per line since the test consumes one token per segment
-	{"  line1", filepath.Join("dir", "TestLineComments"), 1},
-	{"\nline2", filepath.Join("dir", "TestLineComments"), 2},
-	{"\nline3  //line File1.go:100", filepath.Join("dir", "TestLineComments"), 3}, // bad line comment, ignored
-	{"\nline4", filepath.Join("dir", "TestLineComments"), 4},
-	{"\n//line File1.go:100\n  line100", filepath.Join("dir", "File1.go"), 100},
-	{"\n//line  \t :42\n  line1", "", 42},
-	{"\n//line File2.go:200\n  line200", filepath.Join("dir", "File2.go"), 200},
-	{"\n//line foo\t:42\n  line42", filepath.Join("dir", "foo"), 42},
-	{"\n //line foo:42\n  line44", filepath.Join("dir", "foo"), 44},           // bad line comment, ignored
-	{"\n//line foo 42\n  line46", filepath.Join("dir", "foo"), 46},            // bad line comment, ignored
-	{"\n//line foo:42 extra text\n  line48", filepath.Join("dir", "foo"), 48}, // bad line comment, ignored
-	{"\n//line ./foo:42\n  line42", filepath.Join("dir", "foo"), 42},
-	{"\n//line a/b/c/File1.go:100\n  line100", filepath.Join("dir", "a", "b", "c", "File1.go"), 100},
-}
-
-var unixsegments = []segment{
-	{"\n//line /bar:42\n  line42", "/bar", 42},
-}
-
-var winsegments = []segment{
-	{"\n//line c:\\bar:42\n  line42", "c:\\bar", 42},
-	{"\n//line c:\\dir\\File1.go:100\n  line100", "c:\\dir\\File1.go", 100},
-}
-
-// Verify that comments of the form "//line filename:line" are interpreted correctly.
-func TestLineComments(t *testing.T) {
-	segs := segments
-	if runtime.GOOS == "windows" {
-		segs = append(segs, winsegments...)
-	} else {
-		segs = append(segs, unixsegments...)
-	}
-
-	// make source
-	var src string
-	for _, e := range segs {
-		src += e.srcline
-	}
-
-	// verify scan
-	var S Scanner
-	f := token.NewFile(filepath.Join("dir", "TestLineComments"), -1, len(src))
-	S.Init(f, []byte(src), nil, DontInsertCommas)
-	for _, s := range segs {
-		p, _, lit := S.Scan()
-		pos := f.Position(p)
-		checkPosScan(t, lit, p, token.Position{
-			Filename: s.filename,
-			Offset:   pos.Offset,
-			Line:     s.line,
-			Column:   pos.Column,
-		})
-	}
-
-	if S.ErrorCount != 0 {
-		t.Errorf("found %d errors", S.ErrorCount)
-	}
-}
-
 // Verify that initializing the same scanner more than once works correctly.
 func TestInit(t *testing.T) {
 	var s Scanner