Support --if-present

Closes #5670

src/cli.zig

@@ -196,6 +196,7 @@ pub const Arguments = struct {
         clap.parseParam("--inspect <STR>?                  Activate Bun's Debugger") catch unreachable,
         clap.parseParam("--inspect-wait <STR>?             Activate Bun's Debugger, wait for a connection before executing") catch unreachable,
         clap.parseParam("--inspect-brk <STR>?              Activate Bun's Debugger, set breakpoint on first line of code and wait") catch unreachable,
+        clap.parseParam("--if-present                      Exit if the entrypoint does not exist") catch unreachable,
         clap.parseParam("<POS>...                          ") catch unreachable,
     };
 
@@ -538,6 +539,7 @@ pub const Arguments = struct {
                 ctx.preloads = preloads;
             }
 
+            ctx.runtime_options.if_present = args.flag("--if-present");
             ctx.runtime_options.smol = args.flag("--smol");
             if (args.option("--inspect")) |inspect_flag| {
                 ctx.runtime_options.debugger = if (inspect_flag.len == 0)
@@ -1022,6 +1024,7 @@ pub const Command = struct {
     pub const RuntimeOptions = struct {
         smol: bool = false,
         debugger: Debugger = .{ .unspecified = {} },
+        if_present: bool = false,
     };
 
     pub const Context = struct {

src/cli/run_command.zig

@@ -1160,6 +1160,11 @@ pub const RunCommand = struct {
             }
         }
 
+        // If the script is not present and --if-present is passed, exit with 0
+        if (ctx.runtime_options.if_present) {
+            Global.exit(0);
+        }
+
         if (comptime log_errors) {
             Output.prettyError("<r><red>error<r><d>:<r> missing script \"<b>{s}<r>\"\n", .{script_name_to_search});
             Global.exit(1);

test/cli/run/if-present.test.ts

@@ -0,0 +1,26 @@
+import { it, expect } from "bun:test";
+import { bunEnv, bunExe } from "harness";
+
+it("should not error using `bun --if-present`", () => {
+  const { stdout, stderr, exitCode } = Bun.spawnSync({
+    cmd: [bunExe(), "--if-present", "doesnotexist"],
+    env: bunEnv,
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+  expect(stdout.toString()).toBeEmpty();
+  expect(stderr.toString()).toBeEmpty();
+  expect(exitCode).toBe(0);
+});
+
+it("should not error using `bun --if-present`", () => {
+  const { stdout, stderr, exitCode } = Bun.spawnSync({
+    cmd: [bunExe(), "run", "--if-present", "doesnotexist"],
+    env: bunEnv,
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+  expect(stdout.toString()).toBeEmpty();
+  expect(stderr.toString()).toBeEmpty();
+  expect(exitCode).toBe(0);
+});