Add a commit details panel

electron/git-state/commit-metadata.cjs

@@ -0,0 +1,252 @@
+// @ts-check
+
+const { fileSort, getGravatarHash, git, gitBufferWithInput, gitOrEmpty } = require('./common.cjs');
+
+/**
+ * @typedef {import('../../src/types.ts').CommitMetadata} CommitMetadata
+ * @typedef {import('../../src/types.ts').CommitMetadataFile} CommitMetadataFile
+ * @typedef {import('./common.cjs').StatusItem} StatusItem
+ * @typedef {{additions?: number; binary: boolean; deletions?: number; path: string}} NumstatItem
+ */
+
+/** @param {string} email */
+const createGravatarUrl = (email) =>
+  email ? `https://www.gravatar.com/avatar/${getGravatarHash(email)}?s=80&d=identicon` : undefined;
+
+/**
+ * @param {string} raw
+ * @returns {Map<string, NumstatItem>}
+ */
+const parseNumstat = (raw) => {
+  /** @type {Map<string, NumstatItem>} */
+  const stats = new Map();
+  const parts = raw.split('\0');
+
+  for (let index = 0; index < parts.length; ) {
+    const header = parts[index++];
+    if (!header) {
+      // `-z` output ends with a NUL, which produces one empty trailing record.
+      continue;
+    }
+
+    // Paths may contain tabs, so only the first two tabs are numstat separators.
+    const firstTab = header.indexOf('\t');
+    const secondTab = firstTab === -1 ? -1 : header.indexOf('\t', firstTab + 1);
+    if (firstTab === -1 || secondTab === -1) {
+      throw new Error(`Unexpected git numstat record: ${header}`);
+    }
+
+    const additionsText = header.slice(0, firstTab);
+    const deletionsText = header.slice(firstTab + 1, secondTab);
+    const pathField = header.slice(secondTab + 1);
+    const isRename = pathField === '';
+    // For rename records, `--numstat -z` stores old and new paths in the next two records.
+    const path = isRename ? parts[index + 1] : pathField;
+    if (isRename) {
+      index += 2;
+    }
+    if (!path) {
+      throw new Error(`Unexpected git numstat record without a path: ${header}`);
+    }
+
+    const binary = additionsText === '-' || deletionsText === '-';
+    stats.set(path, {
+      binary,
+      path,
+      ...(binary
+        ? {}
+        : {
+            additions: Number(additionsText),
+            deletions: Number(deletionsText),
+          }),
+    });
+  }
+
+  return stats;
+};
+
+/**
+ * @param {string} repoRoot
+ * @param {string} commit
+ * @param {string | undefined} firstParent
+ */
+const readCommitNumstat = async (repoRoot, commit, firstParent) =>
+  parseNumstat(
+    await git(
+      repoRoot,
+      firstParent
+        ? ['diff', '--numstat', '-z', '--find-renames', firstParent, commit]
+        : ['show', '--format=', '--numstat', '-z', '--find-renames', commit],
+    ),
+  );
+
+/** @param {string} raw */
+const parseTrailers = (raw) =>
+  raw.split('\n').flatMap((line) => {
+    const separator = line.indexOf(':');
+    if (separator === -1) {
+      return [];
+    }
+
+    const key = line.slice(0, separator).trim();
+    const value = line.slice(separator + 1).trim();
+    return key && value ? [{ key, value }] : [];
+  });
+
+/**
+ * @param {string} repoRoot
+ * @param {string} subject
+ * @param {string} body
+ */
+const readCommitMessageParts = async (repoRoot, subject, body) => {
+  const message = `${subject}\n\n${body}`;
+  const [rawTrailerBlock, parsedTrailerBlock] = await Promise.all([
+    gitBufferWithInput(
+      repoRoot,
+      ['interpret-trailers', '--only-trailers', '--only-input'],
+      message,
+    ),
+    gitBufferWithInput(repoRoot, ['interpret-trailers', '--parse'], message),
+  ]);
+  const trailerBlock = rawTrailerBlock.toString('utf8').trimEnd();
+  const trimmedBody = body.trimEnd();
+
+  return {
+    body:
+      trailerBlock && trimmedBody.endsWith(trailerBlock)
+        ? trimmedBody.slice(0, -trailerBlock.length).trimEnd()
+        : body,
+    trailers: parseTrailers(parsedTrailerBlock.toString('utf8')),
+  };
+};
+
+/** @param {string} raw */
+const parseCommitMetadataHeader = (raw) => {
+  const parts = raw.split('\0');
+  const [
+    ref,
+    shortRef,
+    parents,
+    authorName,
+    authorEmail,
+    authorDate,
+    committerName,
+    committerEmail,
+    committerDate,
+    subject,
+    body,
+    signatureStatus,
+    signatureSigner,
+    signatureKey,
+  ] = parts;
+
+  return {
+    author: createCommitMetadataPerson(authorName, authorEmail, authorDate),
+    body: body || '',
+    committer: createCommitMetadataPerson(committerName, committerEmail, committerDate),
+    parents: parents ? parents.split(' ').filter(Boolean) : [],
+    ref: ref || '',
+    shortRef: shortRef || '',
+    signature: {
+      ...(signatureKey ? { key: signatureKey.trim() } : {}),
+      ...(signatureSigner ? { signer: signatureSigner } : {}),
+      status: signatureStatus || 'N',
+    },
+    subject: subject || '',
+  };
+};
+
+/**
+ * @param {string | undefined} name
+ * @param {string | undefined} email
+ * @param {string | undefined} date
+ */
+const createCommitMetadataPerson = (name, email, date) => ({
+  date: date || '',
+  email: email || '',
+  gravatarUrl: createGravatarUrl(email || ''),
+  name: name || '',
+});
+
+/**
+ * @param {ReadonlyArray<Pick<StatusItem, 'oldPath' | 'path' | 'status'>>} status
+ * @param {ReadonlyMap<string, NumstatItem>} numstat
+ * @returns {Array<CommitMetadataFile>}
+ */
+const createCommitMetadataFiles = (status, numstat) =>
+  status.map((item) => {
+    const stats = numstat.get(item.path);
+    return {
+      binary: stats?.binary ?? false,
+      oldPath: item.oldPath,
+      path: item.path,
+      status: item.status,
+      ...(stats && !stats.binary
+        ? {
+            additions: stats.additions ?? 0,
+            deletions: stats.deletions ?? 0,
+          }
+        : {}),
+    };
+  });
+
+/** @param {ReadonlyArray<CommitMetadataFile>} files */
+const createCommitMetadataStats = (files) => {
+  const stats = {
+    additions: 0,
+    binaryFiles: 0,
+    deletions: 0,
+    files: files.length,
+    renamedFiles: 0,
+  };
+
+  for (const file of files) {
+    stats.additions += file.additions ?? 0;
+    stats.binaryFiles += file.binary ? 1 : 0;
+    stats.deletions += file.deletions ?? 0;
+    stats.renamedFiles += file.oldPath ? 1 : 0;
+  }
+
+  return stats;
+};
+
+/**
+ * @param {string} repoRoot
+ * @param {string} commit
+ * @param {string | undefined} firstParent
+ * @param {ReadonlyArray<Pick<StatusItem, 'oldPath' | 'path' | 'status'>>} status
+ * @returns {Promise<CommitMetadata>}
+ */
+const readCommitMetadataForCommit = async (repoRoot, commit, firstParent, status) => {
+  const rawHeader = await git(repoRoot, [
+    'show',
+    '-s',
+    '--format=%H%x00%h%x00%P%x00%aN%x00%aE%x00%aI%x00%cN%x00%cE%x00%cI%x00%s%x00%b%x00%G?%x00%GS%x00%GK',
+    commit,
+  ]);
+  const header = parseCommitMetadataHeader(rawHeader);
+  const [numstat, refs, messageParts] = await Promise.all([
+    readCommitNumstat(repoRoot, commit, firstParent),
+    gitOrEmpty(repoRoot, ['for-each-ref', '--points-at', commit, '--format=%(refname:short)']),
+    readCommitMessageParts(repoRoot, header.subject, header.body),
+  ]);
+  const files = createCommitMetadataFiles(status, numstat).sort(fileSort);
+
+  return {
+    ...header,
+    body: messageParts.body,
+    files,
+    ref: commit,
+    refs: refs
+      .split('\n')
+      .map((value) => value.trim())
+      .filter(Boolean)
+      .sort((left, right) => left.localeCompare(right)),
+    stats: createCommitMetadataStats(files),
+    trailers: messageParts.trailers,
+  };
+};
+
+module.exports = {
+  readCommitMetadataForCommit,
+};

electron/git-state/commit.cjs

@@ -16,6 +16,7 @@ const {
   summarizeContent,
   validateRepositoryPath,
 } = require('./common.cjs');
+const { readCommitMetadataForCommit } = require('./commit-metadata.cjs');
 
 /**
  * @typedef {import('../../src/types.ts').ChangedFile} ChangedFile
@@ -447,7 +448,8 @@ const readCommitState = async (launchPath, ref) => {
   const commit = (await git(repoRoot, ['rev-parse', '--verify', `${ref}^{commit}`])).trim();
   const [firstParent] = await readCommitParents(repoRoot, commit);
   const status = await readCommitNameStatus(repoRoot, commit, firstParent, { sort: false });
-  const [oldFiles, newFiles] = await Promise.all([
+  const [commitMetadata, oldFiles, newFiles] = await Promise.all([
+    readCommitMetadataForCommit(repoRoot, commit, firstParent, status),
     firstParent
       ? readGitFiles(
           repoRoot,
@@ -486,6 +488,7 @@ const readCommitState = async (launchPath, ref) => {
     .sort(fileSort);
 
   return {
+    commitMetadata,
     files,
     generatedAt: Date.now(),
     launchPath,