mugit/internal/git/diff.go (view raw)
| 1 | package git |
| 2 | |
| 3 | import ( |
| 4 | "fmt" |
| 5 | "strings" |
| 6 | |
| 7 | "github.com/bluekeyes/go-gitdiff/gitdiff" |
| 8 | "github.com/go-git/go-git/v5/plumbing" |
| 9 | "github.com/go-git/go-git/v5/plumbing/object" |
| 10 | ) |
| 11 | |
| 12 | type TextFragment struct { |
| 13 | Header string |
| 14 | Lines []gitdiff.Line |
| 15 | OldPosition int64 |
| 16 | NewPosition int64 |
| 17 | } |
| 18 | |
| 19 | type Diff struct { |
| 20 | Name struct { |
| 21 | Old string |
| 22 | New string |
| 23 | } |
| 24 | TextFragments []TextFragment |
| 25 | IsBinary bool |
| 26 | IsNew bool |
| 27 | IsDelete bool |
| 28 | IsRename bool |
| 29 | } |
| 30 | |
| 31 | type NiceDiff struct { |
| 32 | Diff []Diff |
| 33 | Commit *Commit |
| 34 | Parents []string // list of short hashes |
| 35 | Stat struct { |
| 36 | FilesChanged int |
| 37 | Insertions int |
| 38 | Deletions int |
| 39 | } |
| 40 | } |
| 41 | |
| 42 | func (g *Repo) Diff() (*NiceDiff, error) { |
| 43 | c, err := g.r.CommitObject(g.h) |
| 44 | if err != nil { |
| 45 | return nil, fmt.Errorf("commit object: %w", err) |
| 46 | } |
| 47 | |
| 48 | patch, parents, err := g.getPatch(c) |
| 49 | if err != nil { |
| 50 | return nil, err |
| 51 | } |
| 52 | |
| 53 | nd, err := parseNiceDiff(patch.String()) |
| 54 | if err != nil { |
| 55 | return nil, err |
| 56 | } |
| 57 | nd.Commit = newCommit(c) |
| 58 | nd.Parents = parents |
| 59 | return nd, nil |
| 60 | } |
| 61 | |
| 62 | func parseNiceDiff(patch string) (*NiceDiff, error) { |
| 63 | nd := &NiceDiff{} |
| 64 | if strings.TrimSpace(patch) == "" { |
| 65 | return nd, nil |
| 66 | } |
| 67 | |
| 68 | diffs, _, err := gitdiff.Parse(strings.NewReader(patch)) |
| 69 | if err != nil { |
| 70 | return nil, fmt.Errorf("parsing diff: %w", err) |
| 71 | } |
| 72 | |
| 73 | nd.Stat.FilesChanged = len(diffs) |
| 74 | nd.Diff = make([]Diff, len(diffs)) |
| 75 | for i, d := range diffs { |
| 76 | diff := &nd.Diff[i] |
| 77 | diff.Name.New = d.NewName |
| 78 | if d.OldName != d.NewName { |
| 79 | diff.Name.Old = d.OldName |
| 80 | } |
| 81 | diff.IsBinary = d.IsBinary |
| 82 | diff.IsNew = d.IsNew |
| 83 | diff.IsDelete = d.IsDelete |
| 84 | diff.IsRename = d.IsRename |
| 85 | |
| 86 | for _, tf := range d.TextFragments { |
| 87 | diff.TextFragments = append(diff.TextFragments, TextFragment{ |
| 88 | Header: tf.Header(), |
| 89 | Lines: tf.Lines, |
| 90 | OldPosition: tf.OldPosition, |
| 91 | NewPosition: tf.NewPosition, |
| 92 | }) |
| 93 | for _, l := range tf.Lines { |
| 94 | switch l.Op { |
| 95 | case gitdiff.OpAdd: |
| 96 | nd.Stat.Insertions += 1 |
| 97 | case gitdiff.OpDelete: |
| 98 | nd.Stat.Deletions += 1 |
| 99 | } |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | return nd, nil |
| 104 | } |
| 105 | |
| 106 | func (g *Repo) getPatch(c *object.Commit) (*object.Patch, []string, error) { |
| 107 | commitTree, err := c.Tree() |
| 108 | if err != nil { |
| 109 | return nil, nil, err |
| 110 | } |
| 111 | |
| 112 | parentTree := &object.Tree{} |
| 113 | if c.NumParents() > 0 { |
| 114 | parent, perr := c.Parents().Next() |
| 115 | if perr != nil { |
| 116 | return nil, nil, perr |
| 117 | } |
| 118 | if parentTree, err = parent.Tree(); err != nil { |
| 119 | return nil, nil, err |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | patch, err := parentTree.Patch(commitTree) |
| 124 | if err != nil { |
| 125 | return nil, nil, fmt.Errorf("patch: %w", err) |
| 126 | } |
| 127 | |
| 128 | parents := make([]string, len(c.ParentHashes)) |
| 129 | for i, h := range c.ParentHashes { |
| 130 | parents[i] = newShortHash(h) |
| 131 | } |
| 132 | |
| 133 | return patch, parents, nil |
| 134 | } |
| 135 | |
| 136 | func (g *Repo) diffBetween(base, head plumbing.Hash) (*NiceDiff, error) { |
| 137 | baseCommit, err := g.r.CommitObject(base) |
| 138 | if err != nil { |
| 139 | return nil, fmt.Errorf("base commit object %s: %w", base, err) |
| 140 | } |
| 141 | headCommit, err := g.r.CommitObject(head) |
| 142 | if err != nil { |
| 143 | return nil, fmt.Errorf("head commit object %s: %w", head, err) |
| 144 | } |
| 145 | |
| 146 | baseTree, err := baseCommit.Tree() |
| 147 | if err != nil { |
| 148 | return nil, fmt.Errorf("base tree %s: %w", base, err) |
| 149 | } |
| 150 | headTree, err := headCommit.Tree() |
| 151 | if err != nil { |
| 152 | return nil, fmt.Errorf("head tree %s: %w", head, err) |
| 153 | } |
| 154 | |
| 155 | patch, err := baseTree.Patch(headTree) |
| 156 | if err != nil { |
| 157 | return nil, fmt.Errorf("tree patch %s..%s: %w", base, head, err) |
| 158 | } |
| 159 | |
| 160 | diff, err := parseNiceDiff(patch.String()) |
| 161 | if err != nil { |
| 162 | return nil, fmt.Errorf("parse tree diff %s..%s: %w", base, head, err) |
| 163 | } |
| 164 | return diff, nil |
| 165 | } |