Golang File.Size方法代码示例

// findQueryPos searches fset for filename and translates the
// specified file-relative byte offsets into token.Pos form.  It
// returns an error if the file was not found or the offsets were out
// of bounds.
//
func findQueryPos(fset *token.FileSet, filename string, startOffset, endOffset int) (start, end token.Pos, err error) {
	var file *token.File
	fset.Iterate(func(f *token.File) bool {
		if sameFile(filename, f.Name()) {
			// (f.Name() is absolute)
			file = f
			return false // done
		}
		return true // continue
	})
	if file == nil {
		err = fmt.Errorf("couldn't find file containing position")
		return
	}

	// Range check [start..end], inclusive of both end-points.

	if 0 <= startOffset && startOffset <= file.Size() {
		start = file.Pos(int(startOffset))
	} else {
		err = fmt.Errorf("start position is beyond end of file")
		return
	}

	if 0 <= endOffset && endOffset <= file.Size() {
		end = file.Pos(int(endOffset))
	} else {
		err = fmt.Errorf("end position is beyond end of file")
		return
	}

	return
}

// parseQueryPos parses a string of the form "file:pos" or
// file:start,end" where pos, start, end match #%d and represent byte
// offsets, and returns the extent to which it refers.
//
// (Numbers without a '#' prefix are reserved for future use,
// e.g. to indicate line/column positions.)
//
func parseQueryPos(fset *token.FileSet, queryPos string) (start, end token.Pos, err error) {
	if queryPos == "" {
		err = fmt.Errorf("no source position specified (-pos flag)")
		return
	}

	colon := strings.LastIndex(queryPos, ":")
	if colon < 0 {
		err = fmt.Errorf("invalid source position -pos=%q", queryPos)
		return
	}
	filename, offset := queryPos[:colon], queryPos[colon+1:]
	startOffset := -1
	endOffset := -1
	if hyphen := strings.Index(offset, ","); hyphen < 0 {
		// e.g. "foo.go:#123"
		startOffset = parseOctothorpDecimal(offset)
		endOffset = startOffset
	} else {
		// e.g. "foo.go:#123,#456"
		startOffset = parseOctothorpDecimal(offset[:hyphen])
		endOffset = parseOctothorpDecimal(offset[hyphen+1:])
	}
	if startOffset < 0 || endOffset < 0 {
		err = fmt.Errorf("invalid -pos offset %q", offset)
		return
	}

	var file *token.File
	fset.Iterate(func(f *token.File) bool {
		if sameFile(filename, f.Name()) {
			// (f.Name() is absolute)
			file = f
			return false // done
		}
		return true // continue
	})
	if file == nil {
		err = fmt.Errorf("couldn't find file containing position -pos=%q", queryPos)
		return
	}

	// Range check [start..end], inclusive of both end-points.

	if 0 <= startOffset && startOffset <= file.Size() {
		start = file.Pos(int(startOffset))
	} else {
		err = fmt.Errorf("start position is beyond end of file -pos=%q", queryPos)
		return
	}

	if 0 <= endOffset && endOffset <= file.Size() {
		end = file.Pos(int(endOffset))
	} else {
		err = fmt.Errorf("end position is beyond end of file -pos=%q", queryPos)
		return
	}

	return
}

func GetLines(f *token.File) []int {
	lines := make([]int, 0, 20)
	l := -1
	for i := f.Base(); i < f.Base()+f.Size(); i++ {
		if f.Line(token.Pos(i)) > l {
			l = f.Line(token.Pos(i))
			lines = append(lines, f.Offset(token.Pos(i)))
		}
	}
	return lines
}

// fileOffsetToPos translates the specified file-relative byte offsets
// into token.Pos form.  It returns an error if the file was not found
// or the offsets were out of bounds.
//
func fileOffsetToPos(file *token.File, startOffset, endOffset int) (start, end token.Pos, err error) {
	// Range check [start..end], inclusive of both end-points.

	if 0 <= startOffset && startOffset <= file.Size() {
		start = file.Pos(int(startOffset))
	} else {
		err = fmt.Errorf("start position is beyond end of file")
		return
	}

	if 0 <= endOffset && endOffset <= file.Size() {
		end = file.Pos(int(endOffset))
	} else {
		err = fmt.Errorf("end position is beyond end of file")
		return
	}

	return
}

// Init prepares the scanner s to tokenize the text src by setting the
// scanner at the beginning of src. The scanner uses the file set file
// for position information and it adds line information for each line.
// It is ok to re-use the same file when re-scanning the same file as
// line information which is already present is ignored. Init causes a
// panic if the file size does not match the src size.
//
// Calls to Scan will invoke the error handler err if they encounter a
// syntax error and err is not nil. Also, for each error encountered,
// the Scanner field ErrorCount is incremented by one. The mode parameter
// determines how comments are handled.
//
// Note that Init may call err if there is an error in the first character
// of the file.
//
func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
	// Explicitly initialize all fields since a scanner may be reused.
	if file.Size() != len(src) {
		panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
	}
	s.file = file
	s.dir, _ = filepath.Split(file.Name())
	s.src = src
	s.err = err
	s.mode = mode

	s.ch = ' '
	s.offset = 0
	s.rdOffset = 0
	s.lineOffset = 0
	s.insertSemi = false
	s.ErrorCount = 0

	s.next()
}

// Init prepares the scanner S to tokenize the text src by setting the
// scanner at the beginning of src. The scanner uses the file set file
// for position information and it adds line information for each line.
// It is ok to re-use the same file when re-scanning the same file as
// line information which is already present is ignored. Init causes a
// panic if the file size does not match the src size.
//
// Calls to Scan will use the error handler err if they encounter a
// syntax error and err is not nil. Also, for each error encountered,
// the Scanner field ErrorCount is incremented by one. The mode parameter
// determines how comments, illegal characters, and semicolons are handled.
//
// Note that Init may call err if there is an error in the first character
// of the file.
//
func (S *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode uint) {
	// Explicitly initialize all fields since a scanner may be reused.
	if file.Size() != len(src) {
		panic("file size does not match src len")
	}
	S.file = file
	S.dir, _ = filepath.Split(file.Name())
	S.src = src
	S.err = err
	S.mode = mode

	S.ch = ' '
	S.offset = 0
	S.rdOffset = 0
	S.lineOffset = 0
	S.insertSemi = false
	S.ErrorCount = 0

	S.next()
}

func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
	if file.Size() != len(src) {
		panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
	}

	s.tokScanner = scan.Scanner{Matcher: getTokenMatcher()}
	s.errScanner = scan.Scanner{Matcher: getErrorMatcher()}
	s.src = skipBOM(src)
	s.tokScanner.SetSource(s.src)
	s.errScanner.SetSource(s.src)

	s.file = file
	s.fileBase = s.file.Base()
	s.dir, _ = filepath.Split(file.Name())
	s.err = err
	s.mode = mode

	s.ErrorCount = 0

	s.preSemi = false
	s.semiPos = 0
}

func (s *Scanner) Init(file *token.File, src []byte, err ErrorHandler, mode Mode) {
	//fmt.Println("Init src", strconv.Quote(string(src)), mode)

	if file.Size() != len(src) {
		panic(fmt.Sprintf("file size (%d) does not match src len (%d)", file.Size(), len(src)))
	}

	s.gombiScanner = newGombiScanner()
	s.SetSource(skipBOM(src))

	s.file = file
	s.dir, _ = filepath.Split(file.Name())
	s.err = err
	s.mode = mode

	s.ErrorCount = 0

	s.lastIsPreSemi = false
	s.commentAfterPreSemi = false
	s.endOfLinePos = 0
	s.endOfLine = 0
	s.commentQueue.reset()
}

// TODO(adonovan): make this a method: func (*token.File) Contains(token.Pos)
func tokenFileContainsPos(f *token.File, pos token.Pos) bool {
	p := int(pos)
	base := f.Base()
	return base <= p && p < base+f.Size()
}