Simplify client proxy port handling

test/server/client-config.test.js

@@ -0,0 +1,45 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+async function withEnv(patch, fn) {
+  const previous = {};
+  for (const key of Object.keys(patch)) {
+    previous[key] = process.env[key];
+    if (patch[key] === undefined) {
+      delete process.env[key];
+    } else {
+      process.env[key] = patch[key];
+    }
+  }
+
+  try {
+    return await fn();
+  } finally {
+    for (const [key, value] of Object.entries(previous)) {
+      if (value === undefined) {
+        delete process.env[key];
+      } else {
+        process.env[key] = value;
+      }
+    }
+  }
+}
+
+test("client proxy range defaults to the single configured proxy port", async () => {
+  await withEnv(
+    {
+      PROXY_PORT: "8082",
+      CLIENT_PROXY_PORT_START: "8082",
+      CLIENT_PROXY_PORT_END: undefined,
+    },
+    async () => {
+      const { settings } = await import(
+        `../../src/server/config.js?single-proxy-port=${Date.now()}`
+      );
+
+      assert.equal(settings.proxyPort, 8082);
+      assert.equal(settings.clientProxyPortStart, 8082);
+      assert.equal(settings.clientProxyPortEnd, 8082);
+    },
+  );
+});