fix(site): keep path separator in terminal websocket URL (#30573)

Enables oxlint's `no-unused-expressions` rule and fixes its violations,
two of which were bugs.

- `terminalWebsocketUrl` built `` `${url.pathname}/` `` without
assigning it, so a base URL with a path (for example a proxy at
`/prefix`) produced `/prefixapi/v2/...`. It now assigns `url.pathname`,
and a test covers it (the test fails without the fix).
- The deployment `experiments` e2e test called `expect(...).toBeVisible`
without `()` or `await`, so those two assertions never ran.

The remaining three hits were `a && f()` and ternaries used as
statements. These are rewritten as `if` statements with no behavior
change.

Depends on #30572

<details>
<summary>Context and findings</summary>

Part of evaluating oxlint's `correctness` category one rule at a time
(see #30572). This rule had 6 hits in 5 files.

The e2e fix makes two assertions active for the first time. Enabled
experiments render with `option-enabled` in `OptionValue`, so they are
expected to pass, but they were not run locally.

Validation: `pnpm run lint` (Biome, oxlint, types, circular deps, React
Compiler, knip) and the full unit suite.

</details>

_Generated by Coder Agents on behalf of @jeremyruppel._

site/.oxlintrc.jsonc

@@ -110,6 +110,7 @@
 		"rules-of-hooks": "error",
 		"refs": "error",
 		"erasing-op": "error",
+		"no-unused-expressions": "error",
 
 		// --- security ---
 		"jsx-no-target-blank": "error",

site/e2e/tests/deployment/general.spec.ts

@@ -24,16 +24,16 @@ test("experiments", async ({ page }) => {
 	await expect(experimentsLocator).toBeVisible();
 
 	// Firstly, check if all enabled experiments are listed
-	expect(
+	await expect(
 		experimentsLocator.locator(
 			`li.option-array-item-${e2eFakeExperiment1}.option-enabled`,
 		),
-	).toBeVisible;
-	expect(
+	).toBeVisible();
+	await expect(
 		experimentsLocator.locator(
 			`li.option-array-item-${e2eFakeExperiment2}.option-enabled`,
 		),
-	).toBeVisible;
+	).toBeVisible();
 
 	// Secondly, check if available experiments are listed
 	for (const experiment of availableExperiments.safe) {

site/src/components/MultiSelectCombobox/MultiSelectCombobox.tsx

@@ -541,7 +541,9 @@ export const MultiSelectCombobox: React.FC<MultiSelectComboboxProps> = ({
 							}}
 							onFocus={(event) => {
 								setOpen(true);
-								triggerSearchOnFocus && onSearch?.(debouncedSearchTerm);
+								if (triggerSearchOnFocus) {
+									onSearch?.(debouncedSearchTerm);
+								}
 								inputProps?.onFocus?.(event);
 							}}
 							placeholder={

site/src/modules/terminal/WorkspaceTerminal.tsx

@@ -103,7 +103,11 @@ export const WorkspaceTerminal = ({
 	const fitAddonRef = useRef<FitAddon | undefined>(undefined);
 	const websocketRef = useRef<Websocket | undefined>(undefined);
 	const handleOpenLink = useEffectEvent((uri: string) => {
-		onOpenLink ? onOpenLink(uri) : window.open(uri, "_blank", "noopener");
+		if (onOpenLink) {
+			onOpenLink(uri);
+		} else {
+			window.open(uri, "_blank", "noopener");
+		}
 	});
 	const handleStatusChange = useEffectEvent((status: ConnectionStatus) => {
 		onStatusChange?.(status);

site/src/testHelpers/storybook.tsx

@@ -142,9 +142,11 @@ export const withWebSocket = (
 					const callback = this.#listeners.get(entry.event);
 
 					if (callback) {
-						entry.event === "message"
-							? callback({ data: entry.data })
-							: callback();
+						if (entry.event === "message") {
+							callback({ data: entry.data });
+						} else {
+							callback();
+						}
 					}
 				}
 			}, 0);

site/src/utils/terminal.test.ts

@@ -1,4 +1,5 @@
-import { describe, expect, it } from "vitest";
+import { describe, expect, it, vi } from "vitest";
+import { API } from "#/api/api";
 import { terminalWebsocketUrl } from "./terminal";
 
 describe("terminalWebsocketUrl", () => {
@@ -21,4 +22,25 @@ describe("terminalWebsocketUrl", () => {
 		);
 		expect(parsed.searchParams.get("reconnect")).toBe("reconnect-token");
 	});
+
+	it("adds a path separator after a base URL path", async () => {
+		vi.spyOn(API, "issueReconnectingPTYSignedToken").mockResolvedValue({
+			signed_token: "token",
+		});
+		const url = await terminalWebsocketUrl(
+			"https://proxy.example.com/prefix",
+			"reconnect-token",
+			"agent-id",
+			undefined,
+			24,
+			80,
+			undefined,
+			undefined,
+			"session-id",
+		);
+
+		expect(new URL(url).pathname).toBe(
+			"/prefix/api/v2/workspaceagents/agent-id/pty",
+		);
+	});
 });

site/src/utils/terminal.ts

@@ -28,7 +28,7 @@ export const terminalWebsocketUrl = async (
 	const url = new URL(baseUrl || `${location.protocol}//${location.host}`);
 	url.protocol = url.protocol === "https:" ? "wss:" : "ws:";
 	if (!url.pathname.endsWith("/")) {
-		`${url.pathname}/`;
+		url.pathname = `${url.pathname}/`;
 	}
 	url.pathname += `api/v2/workspaceagents/${agentId}/pty`;
 	url.search = `?${query.toString()}`;