fix: --port flag no longer sets origin for file imports

Fixes #14096

The --port flag is documented to "Set the default port for Bun.serve",
not to modify asset import URLs or set the origin. Previously, --port
would automatically set the origin, causing file imports like
`import txt from "./a.txt" with { type: "file" }` to incorrectly return
HTTP URLs like `http://localhost:3000/a.txt` instead of file paths.

This fix removes the automatic conversion of --port to origin. Users who
need to set an origin for their bundled assets should use the explicit
--origin flag instead.

Changes:
- Removed automatic port-to-origin conversion in Arguments.zig
- Added regression tests to verify --port doesn't affect file imports

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/cli/Arguments.zig

@@ -803,9 +803,11 @@ pub fn parse(allocator: std.mem.Allocator, ctx: Command.Context, comptime cmd: C
         Bun__Node__UseSystemCA = (Bun__Node__CAStore == .system);
     }
 
-    if (opts.port != null and opts.origin == null) {
-        opts.origin = try std.fmt.allocPrint(allocator, "http://localhost:{d}/", .{opts.port.?});
-    }
+    // Removed: --port should only affect Bun.serve, not set origin for file imports
+    // Users can explicitly use --origin if they want to set the public path
+    // if (opts.port != null and opts.origin == null) {
+    //     opts.origin = try std.fmt.allocPrint(allocator, "http://localhost:{d}/", .{opts.port.?});
+    // }
 
     const output_dir: ?string = null;
     const output_file: ?string = null;

test/regression/issue/14096.test.ts

@@ -0,0 +1,91 @@
+// Regression test for issue #14096: --port should not affect file imports
+// https://github.com/oven-sh/bun/issues/14096
+import { expect, test } from "bun:test";
+import { bunEnv, bunExe, tempDir } from "harness";
+
+test("--port should not convert file imports to HTTP URLs", async () => {
+  using dir = tempDir("issue-14096", {
+    "index.js": `
+      import txt from "./test.txt" with { type: "file" };
+      console.log(txt);
+    `,
+    "test.txt": "hello world",
+  });
+
+  await using proc = Bun.spawn({
+    cmd: [bunExe(), "run", "--port", "3000", "index.js"],
+    env: bunEnv,
+    cwd: String(dir),
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toBe("");
+  expect(exitCode).toBe(0);
+
+  // Should print the file path, NOT http://localhost:3000/test.txt
+  const output = stdout.trim();
+  expect(output).not.toContain("http://");
+  expect(output).not.toContain("localhost");
+  expect(output).not.toContain("3000");
+  expect(output).toEndWith("test.txt");
+});
+
+test("--port should not affect asset imports (image files)", async () => {
+  using dir = tempDir("issue-14096-assets", {
+    "index.js": `
+      import bmp from "./abc.bmp" with { type: "file" };
+      console.log(bmp);
+    `,
+    "abc.bmp": "fake bmp data",
+  });
+
+  await using proc = Bun.spawn({
+    cmd: [bunExe(), "run", "--port", "4000", "index.js"],
+    env: bunEnv,
+    cwd: String(dir),
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toBe("");
+  expect(exitCode).toBe(0);
+
+  // Should print the file path, NOT http://localhost:4000/abc.bmp
+  const output = stdout.trim();
+  expect(output).not.toContain("http://");
+  expect(output).not.toContain("localhost");
+  expect(output).not.toContain("4000");
+  expect(output).toEndWith("abc.bmp");
+});
+
+test("file imports work without --port flag (baseline)", async () => {
+  using dir = tempDir("issue-14096-baseline", {
+    "index.js": `
+      import txt from "./test.txt" with { type: "file" };
+      console.log(txt);
+    `,
+    "test.txt": "hello world",
+  });
+
+  await using proc = Bun.spawn({
+    cmd: [bunExe(), "run", "index.js"],
+    env: bunEnv,
+    cwd: String(dir),
+    stdout: "pipe",
+    stderr: "pipe",
+  });
+
+  const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited]);
+
+  expect(stderr).toBe("");
+  expect(exitCode).toBe(0);
+
+  // Should print the file path
+  const output = stdout.trim();
+  expect(output).toEndWith("test.txt");
+});