fix(server): ensure cli default gets applied if env var is missing

packages/server/src/config/config.test.ts

@@ -0,0 +1,41 @@
+import { afterEach, beforeEach, describe, expect, test } from "bun:test";
+import { resolveOptions } from "./cli-parser";
+import { CLI_OPTION_DEFINITIONS } from "./config";
+
+const ENV_KEYS = Object.values(CLI_OPTION_DEFINITIONS).map((spec) => spec.env);
+
+const clearBlinkEnv = (): (() => void) => {
+  const previous: Record<string, string | undefined> = {};
+  for (const key of ENV_KEYS) {
+    previous[key] = process.env[key];
+    delete process.env[key];
+  }
+  return () => {
+    for (const key of ENV_KEYS) {
+      const value = previous[key];
+      if (value === undefined) {
+        delete process.env[key];
+      } else {
+        process.env[key] = value;
+      }
+    }
+  };
+};
+
+let restoreEnv: (() => void) | undefined;
+
+beforeEach(() => {
+  restoreEnv = clearBlinkEnv();
+});
+
+afterEach(() => {
+  restoreEnv?.();
+  restoreEnv = undefined;
+});
+
+describe("resolveOptions", () => {
+  test("uses default port when BLINK_PORT is unset", () => {
+    const options = resolveOptions({});
+    expect(options.port).toBe(3005);
+  });
+});

packages/server/src/config/config.ts

@@ -152,9 +152,13 @@ export const parseCliOptionValue = <K extends CliOptionKey>(
 
 export const getCliEnvValue = <K extends CliOptionKey>(
   key: K
-): CliOptionValue<K> => {
+): CliOptionValue<K> | undefined => {
   const spec = CLI_OPTION_DEFINITIONS[key];
-  return parseCliOptionValue(key, process.env[spec.env], "env");
+  const rawValue = process.env[spec.env];
+  if (rawValue === undefined) {
+    return undefined;
+  }
+  return parseCliOptionValue(key, rawValue, "env");
 };
 
 export function getBlinkServerConfigDir(): string {