veryroundbird.house
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.sh/tangled.sh/core/patchutil"
16 "tangled.sh/tangled.sh/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 for _, l := range tf.Lines {
68 switch l.Op {
69 case gitdiff.OpAdd:
70 nd.Stat.Insertions += 1
71 case gitdiff.OpDelete:
72 nd.Stat.Deletions += 1
73 }
74 }
75 }
76
77 nd.Diff = append(nd.Diff, ndiff)
78 }
79
80 nd.Stat.FilesChanged = len(diffs)
81 nd.Commit.This = c.Hash.String()
82 nd.Commit.PGPSignature = c.PGPSignature
83 nd.Commit.Committer = c.Committer
84 nd.Commit.Tree = c.TreeHash.String()
85
86 if parent.Hash.IsZero() {
87 nd.Commit.Parent = ""
88 } else {
89 nd.Commit.Parent = parent.Hash.String()
90 }
91 nd.Commit.Author = c.Author
92 nd.Commit.Message = c.Message
93
94 if v, ok := c.ExtraHeaders["change-id"]; ok {
95 nd.Commit.ChangedId = string(v)
96 }
97
98 return &nd, nil
99}
100
101func (g *GitRepo) DiffTree(commit1, commit2 *object.Commit) (*types.DiffTree, error) {
102 tree1, err := commit1.Tree()
103 if err != nil {
104 return nil, err
105 }
106
107 tree2, err := commit2.Tree()
108 if err != nil {
109 return nil, err
110 }
111
112 diff, err := object.DiffTree(tree1, tree2)
113 if err != nil {
114 return nil, err
115 }
116
117 patch, err := diff.Patch()
118 if err != nil {
119 return nil, err
120 }
121
122 diffs, _, err := gitdiff.Parse(strings.NewReader(patch.String()))
123 if err != nil {
124 return nil, err
125 }
126
127 return &types.DiffTree{
128 Rev1: commit1.Hash.String(),
129 Rev2: commit2.Hash.String(),
130 Patch: patch.String(),
131 Diff: diffs,
132 }, nil
133}
134
135// FormatPatch generates a git-format-patch output between two commits,
136// and returns the raw format-patch series, a parsed FormatPatch and an error.
137func (g *GitRepo) formatSinglePatch(commit plumbing.Hash, extraArgs ...string) (string, *types.FormatPatch, error) {
138 var stdout bytes.Buffer
139
140 args := []string{
141 "-C",
142 g.path,
143 "format-patch",
144 "-1",
145 commit.String(),
146 "--stdout",
147 }
148 args = append(args, extraArgs...)
149
150 cmd := exec.Command("git", args...)
151 cmd.Stdout = &stdout
152 cmd.Stderr = os.Stderr
153 err := cmd.Run()
154 if err != nil {
155 return "", nil, err
156 }
157
158 formatPatch, err := patchutil.ExtractPatches(stdout.String())
159 if err != nil {
160 return "", nil, err
161 }
162
163 if len(formatPatch) > 1 {
164 return "", nil, fmt.Errorf("running format-patch on single commit produced more than on patch")
165 }
166
167 return stdout.String(), &formatPatch[0], nil
168}
169
170func (g *GitRepo) ResolveRevision(revStr string) (*object.Commit, error) {
171 rev, err := g.r.ResolveRevision(plumbing.Revision(revStr))
172 if err != nil {
173 return nil, fmt.Errorf("resolving revision %s: %w", revStr, err)
174 }
175
176 commit, err := g.r.CommitObject(*rev)
177 if err != nil {
178
179 return nil, fmt.Errorf("getting commit for %s: %w", revStr, err)
180 }
181
182 return commit, nil
183}
184
185func (g *GitRepo) commitsBetween(newCommit, oldCommit *object.Commit) ([]*object.Commit, error) {
186 var commits []*object.Commit
187
188 output, err := g.revList(
189 "--no-merges", // format-patch explicitly prepares only non-merges
190 fmt.Sprintf("%s..%s", oldCommit.Hash.String(), newCommit.Hash.String()),
191 )
192 if err != nil {
193 return nil, fmt.Errorf("revlist: %w", err)
194 }
195
196 lines := strings.Split(strings.TrimSpace(string(output)), "\n")
197 if len(lines) == 1 && lines[0] == "" {
198 return commits, nil
199 }
200
201 for _, item := range lines {
202 obj, err := g.r.CommitObject(plumbing.NewHash(item))
203 if err != nil {
204 continue
205 }
206 commits = append(commits, obj)
207 }
208
209 return commits, nil
210}
211
212func (g *GitRepo) FormatPatch(base, commit2 *object.Commit) (string, []types.FormatPatch, error) {
213 // get list of commits between commit2 and base
214 commits, err := g.commitsBetween(commit2, base)
215 if err != nil {
216 return "", nil, fmt.Errorf("failed to get commits: %w", err)
217 }
218
219 // reverse the list so we start from the oldest one and go up to the most recent one
220 slices.Reverse(commits)
221
222 var allPatchesContent strings.Builder
223 var allPatches []types.FormatPatch
224
225 for _, commit := range commits {
226 changeId := ""
227 if val, ok := commit.ExtraHeaders["change-id"]; ok {
228 changeId = string(val)
229 }
230
231 var additionalArgs []string
232 if changeId != "" {
233 additionalArgs = append(additionalArgs, "--add-header", fmt.Sprintf("Change-Id: %s", changeId))
234 }
235
236 stdout, patch, err := g.formatSinglePatch(commit.Hash, additionalArgs...)
237 if err != nil {
238 return "", nil, fmt.Errorf("failed to format patch for commit %s: %w", commit.Hash.String(), err)
239 }
240
241 allPatchesContent.WriteString(stdout)
242 allPatchesContent.WriteString("\n")
243
244 allPatches = append(allPatches, *patch)
245 }
246
247 return allPatchesContent.String(), allPatches, nil
248}