Avoid potentially expensive fetching of tags

Right now, there is no problem: GitGitGadget uses a couple of Azure
Pipelines that all run on the same, single runner inside a dedicated
pool, and this runner has a persistent clone of the `gitgitgadget/git`
repository.

However, my current plan is to migrate to GitHub Actions, away from
that self-hosted runner, which means that there is no persistent clone
to work with. Therefore, a local Git repository has to be initialized in
every workflow run, and to make that efficient (and fast!), only the
minimal set of refs is fetched. That idea works only when preventing
Git from _implicitly_ fetching all tags, so let's do that.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

lib/ci-helper.ts

@@ -524,7 +524,7 @@ export class CIHelper {
             const prKey = getPullRequestKeyFromURL(prMeta.pullRequestURL);
             const fetchURL = `https://github.com/${prKey.owner}/${prKey.repo}`;
             const fetchRef = `refs/pull/${prKey.pull_number}/head`;
-            await git(["fetch", fetchURL, fetchRef, prMeta.latestTag], {
+            await git(["fetch", "--no-tags", fetchURL, fetchRef, prMeta.latestTag], {
                 workDir: this.workDir,
             });
         }

lib/git-notes.ts

@@ -39,7 +39,7 @@ export class GitNotes {
                 // wait a while before trying again to push (after fetching the remote notes ref and merging it)
                 await sleep(backoff);
 
-                const output = await git(["fetch", "--porcelain", url, "--", `${this.notesRef}`], {
+                const output = await git(["fetch", "--porcelain", "--no-tags", url, "--", `${this.notesRef}`], {
                     workDir: this.workDir,
                 });
                 // parse the output to obtain the OID of the remote notes ref
@@ -122,7 +122,7 @@ export class GitNotes {
 
     public async update(url: string): Promise<void> {
         if (this.notesRef.match(/^refs\/notes\/(gitgitgadget|commit-to-mail|mail-to-commit)$/)) {
-            await git(["fetch", url, `+${this.notesRef}:${this.notesRef}`], { workDir: this.workDir });
+            await git(["fetch", "--no-tags", url, `+${this.notesRef}:${this.notesRef}`], { workDir: this.workDir });
         } else {
             throw new Error(`Don't know how to update ${this.notesRef}`);
         }

lib/gitgitgadget.ts

@@ -59,7 +59,13 @@ export class GitGitGadget {
 
         // Always fetch the Git notes first thing
         await git(
-            ["fetch", publishTagsAndNotesToRemote, "--", `+${GitNotes.defaultNotesRef}:${GitNotes.defaultNotesRef}`],
+            [
+                "fetch",
+                "--no-tags",
+                publishTagsAndNotesToRemote,
+                "--",
+                `+${GitNotes.defaultNotesRef}:${GitNotes.defaultNotesRef}`,
+            ],
             { workDir },
         );
 
@@ -215,6 +221,7 @@ export class GitGitGadget {
         const pullRequestMerge = `refs/pull/${pullRequestNumber}/merge`;
         const args = [
             "fetch",
+            "--no-tags",
             this.publishTagsAndNotesToRemote,
             "--",
             `+${this.notes.notesRef}:${this.notes.notesRef}`,
@@ -233,9 +240,12 @@ export class GitGitGadget {
         if (repositoryOwner === this.config.repo.owner) {
             args.push(...prArgs);
         } else {
-            await git(["fetch", `https://github.com/${repositoryOwner}/${this.config.repo.name}`, ...prArgs], {
-                workDir: this.workDir,
-            });
+            await git(
+                ["fetch", "--no-tags", `https://github.com/${repositoryOwner}/${this.config.repo.name}`, ...prArgs],
+                {
+                    workDir: this.workDir,
+                },
+            );
         }
         await git(args, { workDir: this.workDir });
 
@@ -249,6 +259,7 @@ export class GitGitGadget {
         await git(
             [
                 "fetch",
+                "--no-tags",
                 this.publishTagsAndNotesToRemote,
                 "--",
                 `+${GitNotes.defaultNotesRef}:${GitNotes.defaultNotesRef}`,

lib/mail-commit-mapping.ts

@@ -43,9 +43,17 @@ export class MailCommitMapping {
         }
         if (refs.length) {
             console.log(`Updating mail-to-commit/refs: ${refs.join(", ")}`);
-            await git(["fetch", `https://github.com/${this.config.repo.owner}/${this.config.repo.name}`, ...refs], {
-                workDir: this.workDir,
-            });
+            await git(
+                [
+                    "fetch",
+                    "--no-tags",
+                    `https://github.com/${this.config.repo.owner}/${this.config.repo.name}`,
+                    ...refs,
+                ],
+                {
+                    workDir: this.workDir,
+                },
+            );
         }
     }
 }