refactor: replace gitdiff with external package

1 files changed, 0 insertions, 281 deletions

diff --git a/internal/gitdiff/format.go b/internal/gitdiff/format.go
deleted file mode 100644
index d97aba9..0000000
--- a/internal/gitdiff/format.go
+++ /dev/null
@@ -1,281 +0,0 @@
-package gitdiff
-
-import (
-	"bytes"
-	"compress/zlib"
-	"fmt"
-	"io"
-	"strconv"
-)
-
-type formatter struct {
-	w   io.Writer
-	err error
-}
-
-func newFormatter(w io.Writer) *formatter {
-	return &formatter{w: w}
-}
-
-func (fm *formatter) Write(p []byte) (int, error) {
-	if fm.err != nil {
-		return len(p), nil
-	}
-	if _, err := fm.w.Write(p); err != nil {
-		fm.err = err
-	}
-	return len(p), nil
-}
-
-func (fm *formatter) WriteString(s string) (int, error) {
-	fm.Write([]byte(s))
-	return len(s), nil
-}
-
-func (fm *formatter) WriteByte(c byte) error {
-	fm.Write([]byte{c})
-	return nil
-}
-
-func (fm *formatter) WriteQuotedName(s string) {
-	qpos := 0
-	for i := 0; i < len(s); i++ {
-		ch := s[i]
-		if q, quoted := quoteByte(ch); quoted {
-			if qpos == 0 {
-				fm.WriteByte('"')
-			}
-			fm.WriteString(s[qpos:i])
-			fm.Write(q)
-			qpos = i + 1
-		}
-	}
-	fm.WriteString(s[qpos:])
-	if qpos > 0 {
-		fm.WriteByte('"')
-	}
-}
-
-var quoteEscapeTable = map[byte]byte{
-	'\a': 'a',
-	'\b': 'b',
-	'\t': 't',
-	'\n': 'n',
-	'\v': 'v',
-	'\f': 'f',
-	'\r': 'r',
-	'"':  '"',
-	'\\': '\\',
-}
-
-func quoteByte(b byte) ([]byte, bool) {
-	if q, ok := quoteEscapeTable[b]; ok {
-		return []byte{'\\', q}, true
-	}
-	if b < 0x20 || b >= 0x7F {
-		return []byte{
-			'\\',
-			'0' + (b>>6)&0o3,
-			'0' + (b>>3)&0o7,
-			'0' + (b>>0)&0o7,
-		}, true
-	}
-	return nil, false
-}
-
-func (fm *formatter) FormatFile(f *File) {
-	fm.WriteString("diff --git ")
-
-	var aName, bName string
-	switch {
-	case f.OldName == "":
-		aName = f.NewName
-		bName = f.NewName
-
-	case f.NewName == "":
-		aName = f.OldName
-		bName = f.OldName
-
-	default:
-		aName = f.OldName
-		bName = f.NewName
-	}
-
-	fm.WriteQuotedName("a/" + aName)
-	fm.WriteByte(' ')
-	fm.WriteQuotedName("b/" + bName)
-	fm.WriteByte('\n')
-
-	if f.OldMode != 0 {
-		if f.IsDelete {
-			fmt.Fprintf(fm, "deleted file mode %o\n", f.OldMode)
-		} else if f.NewMode != 0 {
-			fmt.Fprintf(fm, "old mode %o\n", f.OldMode)
-		}
-	}
-
-	if f.NewMode != 0 {
-		if f.IsNew {
-			fmt.Fprintf(fm, "new file mode %o\n", f.NewMode)
-		} else if f.OldMode != 0 {
-			fmt.Fprintf(fm, "new mode %o\n", f.NewMode)
-		}
-	}
-
-	if f.Score > 0 {
-		if f.IsCopy || f.IsRename {
-			fmt.Fprintf(fm, "similarity index %d%%\n", f.Score)
-		} else {
-			fmt.Fprintf(fm, "dissimilarity index %d%%\n", f.Score)
-		}
-	}
-
-	if f.IsCopy {
-		if f.OldName != "" {
-			fm.WriteString("copy from ")
-			fm.WriteQuotedName(f.OldName)
-			fm.WriteByte('\n')
-		}
-		if f.NewName != "" {
-			fm.WriteString("copy to ")
-			fm.WriteQuotedName(f.NewName)
-			fm.WriteByte('\n')
-		}
-	}
-
-	if f.IsRename {
-		if f.OldName != "" {
-			fm.WriteString("rename from ")
-			fm.WriteQuotedName(f.OldName)
-			fm.WriteByte('\n')
-		}
-		if f.NewName != "" {
-			fm.WriteString("rename to ")
-			fm.WriteQuotedName(f.NewName)
-			fm.WriteByte('\n')
-		}
-	}
-
-	if f.OldOIDPrefix != "" && f.NewOIDPrefix != "" {
-		fmt.Fprintf(fm, "index %s..%s", f.OldOIDPrefix, f.NewOIDPrefix)
-
-		// Mode is only included on the index line when it is not changing
-		if f.OldMode != 0 && ((f.NewMode == 0 && !f.IsDelete) || f.OldMode == f.NewMode) {
-			fmt.Fprintf(fm, " %o", f.OldMode)
-		}
-
-		fm.WriteByte('\n')
-	}
-
-	if f.IsBinary {
-		if f.BinaryFragment == nil {
-			fm.WriteString("Binary files ")
-			fm.WriteQuotedName("a/" + aName)
-			fm.WriteString(" and ")
-			fm.WriteQuotedName("b/" + bName)
-			fm.WriteString(" differ\n")
-		} else {
-			fm.WriteString("GIT binary patch\n")
-			fm.FormatBinaryFragment(f.BinaryFragment)
-			if f.ReverseBinaryFragment != nil {
-				fm.FormatBinaryFragment(f.ReverseBinaryFragment)
-			}
-		}
-	}
-
-	// The "---" and "+++" lines only appear for text patches with fragments
-	if len(f.TextFragments) > 0 {
-		fm.WriteString("--- ")
-		if f.OldName == "" {
-			fm.WriteString("/dev/null")
-		} else {
-			fm.WriteQuotedName("a/" + f.OldName)
-		}
-		fm.WriteByte('\n')
-
-		fm.WriteString("+++ ")
-		if f.NewName == "" {
-			fm.WriteString("/dev/null")
-		} else {
-			fm.WriteQuotedName("b/" + f.NewName)
-		}
-		fm.WriteByte('\n')
-
-		for _, frag := range f.TextFragments {
-			fm.FormatTextFragment(frag)
-		}
-	}
-}
-
-func (fm *formatter) FormatTextFragment(f *TextFragment) {
-	fm.FormatTextFragmentHeader(f)
-	fm.WriteByte('\n')
-
-	for _, line := range f.Lines {
-		fm.WriteString(line.Op.String())
-		fm.WriteString(line.Line)
-		if line.NoEOL() {
-			fm.WriteString("\n\\ No newline at end of file\n")
-		}
-	}
-}
-
-func (fm *formatter) FormatTextFragmentHeader(f *TextFragment) {
-	fmt.Fprintf(fm, "@@ -%d,%d +%d,%d @@", f.OldPosition, f.OldLines, f.NewPosition, f.NewLines)
-	if f.Comment != "" {
-		fm.WriteByte(' ')
-		fm.WriteString(f.Comment)
-	}
-}
-
-func (fm *formatter) FormatBinaryFragment(f *BinaryFragment) {
-	const (
-		maxBytesPerLine = 52
-	)
-
-	switch f.Method {
-	case BinaryPatchDelta:
-		fm.WriteString("delta ")
-	case BinaryPatchLiteral:
-		fm.WriteString("literal ")
-	}
-	fm.Write(strconv.AppendInt(nil, f.Size, 10))
-	fm.WriteByte('\n')
-
-	data := deflateBinaryChunk(f.Data)
-	n := (len(data) / maxBytesPerLine) * maxBytesPerLine
-
-	buf := make([]byte, base85Len(maxBytesPerLine))
-	for i := 0; i < n; i += maxBytesPerLine {
-		base85Encode(buf, data[i:i+maxBytesPerLine])
-		fm.WriteByte('z')
-		fm.Write(buf)
-		fm.WriteByte('\n')
-	}
-	if remainder := len(data) - n; remainder > 0 {
-		buf = buf[0:base85Len(remainder)]
-
-		sizeChar := byte(remainder)
-		if remainder <= 26 {
-			sizeChar = 'A' + sizeChar - 1
-		} else {
-			sizeChar = 'a' + sizeChar - 27
-		}
-
-		base85Encode(buf, data[n:])
-		fm.WriteByte(sizeChar)
-		fm.Write(buf)
-		fm.WriteByte('\n')
-	}
-	fm.WriteByte('\n')
-}
-
-func deflateBinaryChunk(data []byte) []byte {
-	var b bytes.Buffer
-
-	zw := zlib.NewWriter(&b)
-	_, _ = zw.Write(data)
-	_ = zw.Close()
-
-	return b.Bytes()
-}