Monorepo for Tangled
tangled.org
1package git
2
3import (
4 "bytes"
5 "fmt"
6 "log"
7 "os"
8 "os/exec"
9 "slices"
10 "strings"
11
12 "github.com/bluekeyes/go-gitdiff/gitdiff"
13 "github.com/go-git/go-git/v5/plumbing"
14 "github.com/go-git/go-git/v5/plumbing/object"
15 "tangled.org/core/patchutil"
16 "tangled.org/core/types"
17)
18
19func (g *GitRepo) Diff() (*types.NiceDiff, error) {
20 c, err := g.r.CommitObject(g.h)
21 if err != nil {
22 return nil, fmt.Errorf("commit object: %w", err)
23 }
24
25 patch := &object.Patch{}
26 commitTree, err := c.Tree()
27 parent := &object.Commit{}
28 if err == nil {
29 parentTree := &object.Tree{}
30 if c.NumParents() != 0 {
31 parent, err = c.Parents().Next()
32 if err == nil {
33 parentTree, err = parent.Tree()
34 if err == nil {
35 patch, err = parentTree.Patch(commitTree)
36 if err != nil {
37 return nil, fmt.Errorf("patch: %w", err)
38 }
39 }
40 }
41 } else {
42 patch, err = parentTree.Patch(commitTree)
43 if err != nil {
44 return nil, fmt.Errorf("patch: %w", err)
45 }
46 }
47 }
48
49 diffs, _, err := gitdiff.Parse(strings.NewReader(patch.String()))
50 if err != nil {
51 log.Println(err)
52 }
53
54 nd := types.NiceDiff{}
55 for _, d := range diffs {
56 ndiff := types.Diff{}
57 ndiff.Name.New = d.NewName
58 ndiff.Name.Old = d.OldName
59 ndiff.IsBinary = d.IsBinary
60 ndiff.IsNew = d.IsNew
61 ndiff.IsDelete = d.IsDelete
62 ndiff.IsCopy = d.IsCopy
63 ndiff.IsRename = d.IsRename
64
65 for _, tf := range d.TextFragments {
66 ndiff.TextFragments = append(ndiff.TextFragments, *tf)
67 nd.Stat.Insertions += tf.LinesAdded
68 nd.Stat.Deletions += tf.LinesDeleted
69 }
70
71 nd.Diff = append(nd.Diff, ndiff)
72 }
73
74 nd.Stat.FilesChanged += len(diffs)
75 nd.Commit.FromGoGitCommit(c)
76
77 return &nd, nil
78}
79
80func (g *GitRepo) MergeBase(a, b *object.Commit) (*object.Commit, error) {
81 out, err := g.mergeBase(a.Hash.String(), b.Hash.String())
82 if err != nil {
83 return nil, fmt.Errorf("merge-base %s %s: %w", a.Hash, b.Hash, err)
84 }
85
86 hash := plumbing.NewHash(strings.TrimSpace(string(out)))
87 return g.r.CommitObject(hash)
88}
89
90func (g *GitRepo) DiffTree(commit1, commit2 *object.Commit) (*types.DiffTree, error) {
91 tree1, err := commit1.Tree()
92 if err != nil {
93 return nil, err
94 }
95
96 tree2, err := commit2.Tree()
97 if err != nil {
98 return nil, err
99 }
100
101 diff, err := object.DiffTree(tree1, tree2)
102 if err != nil {
103 return nil, err
104 }
105
106 patch, err := diff.Patch()
107 if err != nil {
108 return nil, err
109 }
110
111 patchStr := patch.String()
112 diffs, _, err := gitdiff.Parse(strings.NewReader(patchStr))
113 if err != nil {
114 return nil, err
115 }
116
117 return &types.DiffTree{
118 Rev1: commit1.Hash.String(),
119 Rev2: commit2.Hash.String(),
120 Patch: patchStr,
121 Diff: diffs,
122 }, nil
123}
124
125// FormatPatch generates a git-format-patch output between two commits,
126// and returns the raw format-patch series, a parsed FormatPatch and an error.
127func (g *GitRepo) formatSinglePatch(commit plumbing.Hash, extraArgs ...string) (string, *types.FormatPatch, error) {
128 var stdout bytes.Buffer
129
130 args := []string{
131 "-C",
132 g.path,
133 "format-patch",
134 "-1",
135 commit.String(),
136 "--stdout",
137 }
138 args = append(args, extraArgs...)
139
140 cmd := exec.Command("git", args...)
141 cmd.Stdout = &stdout
142 cmd.Stderr = os.Stderr
143 err := cmd.Run()
144 if err != nil {
145 return "", nil, err
146 }
147
148 raw := stdout.String()
149 formatPatch, err := patchutil.ExtractPatches(raw)
150 if err != nil {
151 return "", nil, err
152 }
153
154 if len(formatPatch) > 1 {
155 return "", nil, fmt.Errorf("running format-patch on single commit produced more than on patch")
156 }
157
158 return raw, &formatPatch[0], nil
159}
160
161func (g *GitRepo) ResolveRevision(revStr string) (*object.Commit, error) {
162 rev, err := g.r.ResolveRevision(plumbing.Revision(revStr))
163 if err != nil {
164 return nil, fmt.Errorf("resolving revision %s: %w", revStr, err)
165 }
166
167 commit, err := g.r.CommitObject(*rev)
168 if err != nil {
169
170 return nil, fmt.Errorf("getting commit for %s: %w", revStr, err)
171 }
172
173 return commit, nil
174}
175
176func (g *GitRepo) commitsBetween(newCommit, oldCommit *object.Commit) ([]*object.Commit, error) {
177 var commits []*object.Commit
178
179 output, err := g.revList(
180 "--no-merges", // format-patch explicitly prepares only non-merges
181 fmt.Sprintf("%s..%s", oldCommit.Hash.String(), newCommit.Hash.String()),
182 )
183 if err != nil {
184 return nil, fmt.Errorf("revlist: %w", err)
185 }
186
187 lines := strings.Split(strings.TrimSpace(string(output)), "\n")
188 if len(lines) == 1 && lines[0] == "" {
189 return commits, nil
190 }
191
192 for _, item := range lines {
193 obj, err := g.r.CommitObject(plumbing.NewHash(item))
194 if err != nil {
195 continue
196 }
197 commits = append(commits, obj)
198 }
199
200 return commits, nil
201}
202
203func (g *GitRepo) FormatPatch(base, commit2 *object.Commit) (string, []types.FormatPatch, error) {
204 // get list of commits between commit2 and base
205 commits, err := g.commitsBetween(commit2, base)
206 if err != nil {
207 return "", nil, fmt.Errorf("failed to get commits: %w", err)
208 }
209
210 // reverse the list so we start from the oldest one and go up to the most recent one
211 slices.Reverse(commits)
212
213 var allPatchesContent strings.Builder
214 var allPatches []types.FormatPatch
215
216 for _, commit := range commits {
217 changeId := ""
218 if val, ok := commit.ExtraHeaders["change-id"]; ok {
219 changeId = string(val)
220 }
221
222 var additionalArgs []string
223 if changeId != "" {
224 additionalArgs = append(additionalArgs, "--add-header", fmt.Sprintf("Change-Id: %s", changeId))
225 }
226
227 stdout, patch, err := g.formatSinglePatch(commit.Hash, additionalArgs...)
228 if err != nil {
229 return "", nil, fmt.Errorf("failed to format patch for commit %s: %w", commit.Hash.String(), err)
230 }
231
232 allPatchesContent.WriteString(stdout)
233 allPatchesContent.WriteString("\n")
234
235 allPatches = append(allPatches, *patch)
236 }
237
238 return allPatchesContent.String(), allPatches, nil
239}