1 files changed, 0 insertions, 220 deletions
diff --git a/internal/gitdiff/io.go b/internal/gitdiff/io.go
deleted file mode 100644
index 8143238..0000000
--- a/internal/gitdiff/io.go
+++ /dev/null
@@ -1,220 +0,0 @@
-package gitdiff
-
-import (
-	"errors"
-	"io"
-)
-
-const (
-	byteBufferSize  = 32 * 1024 // from io.Copy
-	lineBufferSize  = 32
-	indexBufferSize = 1024
-)
-
-// LineReaderAt is the interface that wraps the ReadLinesAt method.
-//
-// ReadLinesAt reads len(lines) into lines starting at line offset. It returns
-// the number of lines read (0 <= n <= len(lines)) and any error encountered.
-// Line numbers are zero-indexed.
-//
-// If n < len(lines), ReadLinesAt returns a non-nil error explaining why more
-// lines were not returned.
-//
-// Lines read by ReadLinesAt include the newline character. The last line does
-// not have a final newline character if the input ends without one.
-type LineReaderAt interface {
-	ReadLinesAt(lines [][]byte, offset int64) (n int, err error)
-}
-
-type lineReaderAt struct {
-	r     io.ReaderAt
-	index []int64
-	eof   bool
-}
-
-func (r *lineReaderAt) ReadLinesAt(lines [][]byte, offset int64) (n int, err error) {
-	if offset < 0 {
-		return 0, errors.New("ReadLinesAt: negative offset")
-	}
-	if len(lines) == 0 {
-		return 0, nil
-	}
-
-	count := len(lines)
-	startLine := offset
-	endLine := startLine + int64(count)
-
-	if endLine > int64(len(r.index)) && !r.eof {
-		if err := r.indexTo(endLine); err != nil {
-			return 0, err
-		}
-	}
-	if startLine >= int64(len(r.index)) {
-		return 0, io.EOF
-	}
-
-	buf, byteOffset, err := r.readBytes(startLine, int64(count))
-	if err != nil {
-		return 0, err
-	}
-
-	for n = 0; n < count && startLine+int64(n) < int64(len(r.index)); n++ {
-		lineno := startLine + int64(n)
-		start, end := int64(0), r.index[lineno]-byteOffset
-		if lineno > 0 {
-			start = r.index[lineno-1] - byteOffset
-		}
-		lines[n] = buf[start:end]
-	}
-
-	if n < count {
-		return n, io.EOF
-	}
-	return n, nil
-}
-
-// indexTo reads data and computes the line index until there is information
-// for line or a read returns io.EOF. It returns an error if and only if there
-// is an error reading data.
-func (r *lineReaderAt) indexTo(line int64) error {
-	var buf [indexBufferSize]byte
-
-	offset := r.lastOffset()
-	for int64(len(r.index)) < line {
-		n, err := r.r.ReadAt(buf[:], offset)
-		if err != nil && err != io.EOF {
-			return err
-		}
-		for _, b := range buf[:n] {
-			offset++
-			if b == '\n' {
-				r.index = append(r.index, offset)
-			}
-		}
-		if err == io.EOF {
-			if offset > r.lastOffset() {
-				r.index = append(r.index, offset)
-			}
-			r.eof = true
-			break
-		}
-	}
-	return nil
-}
-
-func (r *lineReaderAt) lastOffset() int64 {
-	if n := len(r.index); n > 0 {
-		return r.index[n-1]
-	}
-	return 0
-}
-
-// readBytes reads the bytes of the n lines starting at line and returns the
-// bytes and the offset of the first byte in the underlying source.
-func (r *lineReaderAt) readBytes(line, n int64) (b []byte, offset int64, err error) {
-	indexLen := int64(len(r.index))
-
-	var size int64
-	if line > indexLen {
-		offset = r.index[indexLen-1]
-	} else if line > 0 {
-		offset = r.index[line-1]
-	}
-	if n > 0 {
-		if line+n > indexLen {
-			size = r.index[indexLen-1] - offset
-		} else {
-			size = r.index[line+n-1] - offset
-		}
-	}
-
-	b = make([]byte, size)
-	if _, err := r.r.ReadAt(b, offset); err != nil {
-		if err == io.EOF {
-			err = errors.New("ReadLinesAt: corrupt line index or changed source data")
-		}
-		return nil, 0, err
-	}
-	return b, offset, nil
-}
-
-func isLen(r io.ReaderAt, n int64) (bool, error) {
-	off := n - 1
-	if off < 0 {
-		off = 0
-	}
-
-	var b [2]byte
-	nr, err := r.ReadAt(b[:], off)
-	if err == io.EOF {
-		return (n == 0 && nr == 0) || (n > 0 && nr == 1), nil
-	}
-	return false, err
-}
-
-// copyFrom writes bytes starting from offset off in src to dst stopping at the
-// end of src or at the first error. copyFrom returns the number of bytes
-// written and any error.
-func copyFrom(dst io.Writer, src io.ReaderAt, off int64) (written int64, err error) {
-	buf := make([]byte, byteBufferSize)
-	for {
-		nr, rerr := src.ReadAt(buf, off)
-		if nr > 0 {
-			nw, werr := dst.Write(buf[0:nr])
-			if nw > 0 {
-				written += int64(nw)
-			}
-			if werr != nil {
-				err = werr
-				break
-			}
-			if nr != nw {
-				err = io.ErrShortWrite
-				break
-			}
-			off += int64(nr)
-		}
-		if rerr != nil {
-			if rerr != io.EOF {
-				err = rerr
-			}
-			break
-		}
-	}
-	return written, err
-}
-
-// copyLinesFrom writes lines starting from line off in src to dst stopping at
-// the end of src or at the first error. copyLinesFrom returns the number of
-// lines written and any error.
-func copyLinesFrom(dst io.Writer, src LineReaderAt, off int64) (written int64, err error) {
-	buf := make([][]byte, lineBufferSize)
-ReadLoop:
-	for {
-		nr, rerr := src.ReadLinesAt(buf, off)
-		if nr > 0 {
-			for _, line := range buf[0:nr] {
-				nw, werr := dst.Write(line)
-				if nw > 0 {
-					written++
-				}
-				if werr != nil {
-					err = werr
-					break ReadLoop
-				}
-				if len(line) != nw {
-					err = io.ErrShortWrite
-					break ReadLoop
-				}
-			}
-			off += int64(nr)
-		}
-		if rerr != nil {
-			if rerr != io.EOF {
-				err = rerr
-			}
-			break
-		}
-	}
-	return written, err
-}