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 diffs, _, err := gitdiff.Parse(strings.NewReader(patch.String()))
112 if err != nil {
113 return nil, err
114 }
115
116 return &types.DiffTree{
117 Rev1: commit1.Hash.String(),
118 Rev2: commit2.Hash.String(),
119 Patch: patch.String(),
120 Diff: diffs,
121 }, nil
122}
123
124// FormatPatch generates a git-format-patch output between two commits,
125// and returns the raw format-patch series, a parsed FormatPatch and an error.
126func (g *GitRepo) formatSinglePatch(commit plumbing.Hash, extraArgs ...string) (string, *types.FormatPatch, error) {
127 var stdout bytes.Buffer
128
129 args := []string{
130 "-C",
131 g.path,
132 "format-patch",
133 "-1",
134 commit.String(),
135 "--stdout",
136 }
137 args = append(args, extraArgs...)
138
139 cmd := exec.Command("git", args...)
140 cmd.Stdout = &stdout
141 cmd.Stderr = os.Stderr
142 err := cmd.Run()
143 if err != nil {
144 return "", nil, err
145 }
146
147 formatPatch, err := patchutil.ExtractPatches(stdout.String())
148 if err != nil {
149 return "", nil, err
150 }
151
152 if len(formatPatch) > 1 {
153 return "", nil, fmt.Errorf("running format-patch on single commit produced more than on patch")
154 }
155
156 return stdout.String(), &formatPatch[0], nil
157}
158
159func (g *GitRepo) ResolveRevision(revStr string) (*object.Commit, error) {
160 rev, err := g.r.ResolveRevision(plumbing.Revision(revStr))
161 if err != nil {
162 return nil, fmt.Errorf("resolving revision %s: %w", revStr, err)
163 }
164
165 commit, err := g.r.CommitObject(*rev)
166 if err != nil {
167
168 return nil, fmt.Errorf("getting commit for %s: %w", revStr, err)
169 }
170
171 return commit, nil
172}
173
174func (g *GitRepo) commitsBetween(newCommit, oldCommit *object.Commit) ([]*object.Commit, error) {
175 var commits []*object.Commit
176
177 output, err := g.revList(
178 "--no-merges", // format-patch explicitly prepares only non-merges
179 fmt.Sprintf("%s..%s", oldCommit.Hash.String(), newCommit.Hash.String()),
180 )
181 if err != nil {
182 return nil, fmt.Errorf("revlist: %w", err)
183 }
184
185 lines := strings.Split(strings.TrimSpace(string(output)), "\n")
186 if len(lines) == 1 && lines[0] == "" {
187 return commits, nil
188 }
189
190 for _, item := range lines {
191 obj, err := g.r.CommitObject(plumbing.NewHash(item))
192 if err != nil {
193 continue
194 }
195 commits = append(commits, obj)
196 }
197
198 return commits, nil
199}
200
201func (g *GitRepo) FormatPatch(base, commit2 *object.Commit) (string, []types.FormatPatch, error) {
202 // get list of commits between commit2 and base
203 commits, err := g.commitsBetween(commit2, base)
204 if err != nil {
205 return "", nil, fmt.Errorf("failed to get commits: %w", err)
206 }
207
208 // reverse the list so we start from the oldest one and go up to the most recent one
209 slices.Reverse(commits)
210
211 var allPatchesContent strings.Builder
212 var allPatches []types.FormatPatch
213
214 for _, commit := range commits {
215 changeId := ""
216 if val, ok := commit.ExtraHeaders["change-id"]; ok {
217 changeId = string(val)
218 }
219
220 var additionalArgs []string
221 if changeId != "" {
222 additionalArgs = append(additionalArgs, "--add-header", fmt.Sprintf("Change-Id: %s", changeId))
223 }
224
225 stdout, patch, err := g.formatSinglePatch(commit.Hash, additionalArgs...)
226 if err != nil {
227 return "", nil, fmt.Errorf("failed to format patch for commit %s: %w", commit.Hash.String(), err)
228 }
229
230 allPatchesContent.WriteString(stdout)
231 allPatchesContent.WriteString("\n")
232
233 allPatches = append(allPatches, *patch)
234 }
235
236 return allPatchesContent.String(), allPatches, nil
237}