make bun ci work as alias of --frozen-lockfile (like npm ci) (#20590)

Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>

src/cli.zig

@@ -578,6 +578,7 @@ pub const Command = struct {
 
                 break :brk .InstallCommand;
             },
+            RootCommandMatcher.case("ci") => .InstallCommand,
             RootCommandMatcher.case("c"), RootCommandMatcher.case("create") => .CreateCommand,
 
             RootCommandMatcher.case("test") => .TestCommand,

src/install/PackageManager/CommandLineArguments.zig

@@ -712,9 +712,10 @@ pub fn parse(allocator: std.mem.Allocator, comptime subcommand: Subcommand) !Com
     }
 
     var cli = CommandLineArguments{};
+    cli.positionals = args.positionals();
     cli.yarn = args.flag("--yarn");
     cli.production = args.flag("--production");
-    cli.frozen_lockfile = args.flag("--frozen-lockfile");
+    cli.frozen_lockfile = args.flag("--frozen-lockfile") or (cli.positionals.len > 0 and strings.eqlComptime(cli.positionals[0], "ci"));
     cli.no_progress = args.flag("--no-progress");
     cli.dry_run = args.flag("--dry-run");
     cli.global = args.flag("--global");
@@ -920,8 +921,6 @@ pub fn parse(allocator: std.mem.Allocator, comptime subcommand: Subcommand) !Com
         cli.registry = registry;
     }
 
-    cli.positionals = args.positionals();
-
     if (subcommand == .patch and cli.positionals.len < 2) {
         Output.errGeneric("Missing pkg to patch\n", .{});
         Global.crash();

test/cli/install/bun-install.test.ts

@@ -6198,6 +6198,65 @@ it("should handle --frozen-lockfile", async () => {
   expect(await exited).toBe(1);
 });
 
+it("should handle bun ci alias (to --frozen-lockfile)", async () => {
+  let urls: string[] = [];
+  setHandler(dummyRegistry(urls, { "0.0.3": { as: "0.0.3" }, "0.0.5": { as: "0.0.5" } }));
+
+  await writeFile(
+    join(package_dir, "package.json"),
+    JSON.stringify({ name: "foo", version: "0.0.1", dependencies: { baz: "0.0.3" } }),
+  );
+
+  // save the lockfile once
+  expect(
+    await spawn({
+      cmd: [bunExe(), "install"],
+      cwd: package_dir,
+      stdout: "ignore",
+      stdin: "ignore",
+      stderr: "ignore",
+      env,
+    }).exited,
+  ).toBe(0);
+
+  // change version of baz in package.json
+  await writeFile(
+    join(package_dir, "package.json"),
+    JSON.stringify({
+      name: "foo",
+      version: "0.0.1",
+      dependencies: { baz: "0.0.5" },
+    }),
+  );
+
+  const { stderr: stderr1, exited: exited1 } = spawn({
+    cmd: [bunExe(), "ci"],
+    cwd: package_dir,
+    stdout: "pipe",
+    stdin: "pipe",
+    stderr: "pipe",
+    env,
+  });
+
+  const err1 = await new Response(stderr1).text();
+  expect(err1).toContain("error: lockfile had changes, but lockfile is frozen");
+  expect(await exited1).toBe(1);
+
+  // test that it works even if ci isn't first "arg"
+  const { stderr: stderr2, exited: exited2 } = spawn({
+    cmd: [bunExe(), "--save", "ci"],
+    cwd: package_dir,
+    stdout: "pipe",
+    stdin: "pipe",
+    stderr: "pipe",
+    env,
+  });
+
+  const err2 = await new Response(stderr2).text();
+  expect(err2).toContain("error: lockfile had changes, but lockfile is frozen");
+  expect(await exited2).toBe(1);
+});
+
 it("should handle frozenLockfile in config file", async () => {
   let urls: string[] = [];
   setHandler(dummyRegistry(urls, { "0.0.3": { as: "0.0.3" }, "0.0.5": { as: "0.0.5" } }));