+++ /dev/null
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package diff
-
-import (
- "fmt"
- "strings"
-)
-
-// Unified represents a set of edits as a unified diff.
-type Unified struct {
- // From is the name of the original file.
- From string
- // To is the name of the modified file.
- To string
- // Hunks is the set of edit hunks needed to transform the file content.
- Hunks []*Hunk
-}
-
-// Hunk represents a contiguous set of line edits to apply.
-type Hunk struct {
- // The line in the original source where the hunk starts.
- FromLine int
- // The line in the original source where the hunk finishes.
- ToLine int
- // The set of line based edits to apply.
- Lines []Line
-}
-
-// Line represents a single line operation to apply as part of a Hunk.
-type Line struct {
- // Kind is the type of line this represents, deletion, insertion or copy.
- Kind OpKind
- // Content is the content of this line.
- // For deletion it is the line being removed, for all others it is the line
- // to put in the output.
- Content string
-}
-
-// OpKind is used to denote the type of operation a line represents.
-type OpKind int
-
-const (
- // Delete is the operation kind for a line that is present in the input
- // but not in the output.
- Delete OpKind = iota
- // Insert is the operation kind for a line that is new in the output.
- Insert
- // Equal is the operation kind for a line that is the same in the input and
- // output, often used to provide context around edited lines.
- Equal
-)
-
-// String returns a human readable representation of an OpKind. It is not
-// intended for machine processing.
-func (k OpKind) String() string {
- switch k {
- case Delete:
- return "delete"
- case Insert:
- return "insert"
- case Equal:
- return "equal"
- default:
- panic("unknown operation kind")
- }
-}
-
-const (
- edge = 3
- gap = edge * 2
-)
-
-// ToUnified takes a file contents and a sequence of edits, and calculates
-// a unified diff that represents those edits.
-func ToUnified(from, to string, content string, edits []TextEdit) Unified {
- u := Unified{
- From: from,
- To: to,
- }
- if len(edits) == 0 {
- return u
- }
- c, edits, partial := prepareEdits(content, edits)
- if partial {
- edits = lineEdits(content, c, edits)
- }
- lines := splitLines(content)
- var h *Hunk
- last := 0
- toLine := 0
- for _, edit := range edits {
- start := edit.Span.Start().Line() - 1
- end := edit.Span.End().Line() - 1
- switch {
- case h != nil && start == last:
- //direct extension
- case h != nil && start <= last+gap:
- //within range of previous lines, add the joiners
- addEqualLines(h, lines, last, start)
- default:
- //need to start a new hunk
- if h != nil {
- // add the edge to the previous hunk
- addEqualLines(h, lines, last, last+edge)
- u.Hunks = append(u.Hunks, h)
- }
- toLine += start - last
- h = &Hunk{
- FromLine: start + 1,
- ToLine: toLine + 1,
- }
- // add the edge to the new hunk
- delta := addEqualLines(h, lines, start-edge, start)
- h.FromLine -= delta
- h.ToLine -= delta
- }
- last = start
- for i := start; i < end; i++ {
- h.Lines = append(h.Lines, Line{Kind: Delete, Content: lines[i]})
- last++
- }
- if edit.NewText != "" {
- for _, line := range splitLines(edit.NewText) {
- h.Lines = append(h.Lines, Line{Kind: Insert, Content: line})
- toLine++
- }
- }
- }
- if h != nil {
- // add the edge to the final hunk
- addEqualLines(h, lines, last, last+edge)
- u.Hunks = append(u.Hunks, h)
- }
- return u
-}
-
-func splitLines(text string) []string {
- lines := strings.SplitAfter(text, "\n")
- if lines[len(lines)-1] == "" {
- lines = lines[:len(lines)-1]
- }
- return lines
-}
-
-func addEqualLines(h *Hunk, lines []string, start, end int) int {
- delta := 0
- for i := start; i < end; i++ {
- if i < 0 {
- continue
- }
- if i >= len(lines) {
- return delta
- }
- h.Lines = append(h.Lines, Line{Kind: Equal, Content: lines[i]})
- delta++
- }
- return delta
-}
-
-// Format converts a unified diff to the standard textual form for that diff.
-// The output of this function can be passed to tools like patch.
-func (u Unified) Format(f fmt.State, r rune) {
- if len(u.Hunks) == 0 {
- return
- }
- fmt.Fprintf(f, "--- %s\n", u.From)
- fmt.Fprintf(f, "+++ %s\n", u.To)
- for _, hunk := range u.Hunks {
- fromCount, toCount := 0, 0
- for _, l := range hunk.Lines {
- switch l.Kind {
- case Delete:
- fromCount++
- case Insert:
- toCount++
- default:
- fromCount++
- toCount++
- }
- }
- fmt.Fprint(f, "@@")
- if fromCount > 1 {
- fmt.Fprintf(f, " -%d,%d", hunk.FromLine, fromCount)
- } else {
- fmt.Fprintf(f, " -%d", hunk.FromLine)
- }
- if toCount > 1 {
- fmt.Fprintf(f, " +%d,%d", hunk.ToLine, toCount)
- } else {
- fmt.Fprintf(f, " +%d", hunk.ToLine)
- }
- fmt.Fprint(f, " @@\n")
- for _, l := range hunk.Lines {
- switch l.Kind {
- case Delete:
- fmt.Fprintf(f, "-%s", l.Content)
- case Insert:
- fmt.Fprintf(f, "+%s", l.Content)
- default:
- fmt.Fprintf(f, " %s", l.Content)
- }
- if !strings.HasSuffix(l.Content, "\n") {
- fmt.Fprintf(f, "\n\\ No newline at end of file\n")
- }
- }
- }
-}
projects / dotfiles / .git / blobdiff