1use futures::channel::oneshot;
2use futures::{FutureExt, select_biased};
3use gpui::{App, Context, Global, Subscription, Task, Window};
4use std::cell::RefCell;
5use std::rc::Rc;
6use std::sync::LazyLock;
7use std::time::Duration;
8use std::{future::Future, pin::Pin, task::Poll};
9
10#[derive(Default)]
11struct FeatureFlags {
12 flags: Vec<String>,
13 staff: bool,
14}
15
16pub static ZED_DISABLE_STAFF: LazyLock<bool> = LazyLock::new(|| {
17 std::env::var("ZED_DISABLE_STAFF").map_or(false, |value| !value.is_empty() && value != "0")
18});
19
20impl FeatureFlags {
21 fn has_flag<T: FeatureFlag>(&self) -> bool {
22 if T::enabled_for_all() {
23 return true;
24 }
25
26 if self.staff && T::enabled_for_staff() {
27 return true;
28 }
29
30 self.flags.iter().any(|f| f.as_str() == T::NAME)
31 }
32}
33
34impl Global for FeatureFlags {}
35
36/// To create a feature flag, implement this trait on a trivial type and use it as
37/// a generic parameter when called [`FeatureFlagAppExt::has_flag`].
38///
39/// Feature flags are enabled for members of Zed staff by default. To disable this behavior
40/// so you can test flags being disabled, set ZED_DISABLE_STAFF=1 in your environment,
41/// which will force Zed to treat the current user as non-staff.
42pub trait FeatureFlag {
43 const NAME: &'static str;
44
45 /// Returns whether this feature flag is enabled for Zed staff.
46 fn enabled_for_staff() -> bool {
47 true
48 }
49
50 /// Returns whether this feature flag is enabled for everyone.
51 ///
52 /// This is generally done on the server, but we provide this as a way to entirely enable a feature flag client-side
53 /// without needing to remove all of the call sites.
54 fn enabled_for_all() -> bool {
55 false
56 }
57}
58
59pub struct PredictEditsRateCompletionsFeatureFlag;
60impl FeatureFlag for PredictEditsRateCompletionsFeatureFlag {
61 const NAME: &'static str = "predict-edits-rate-completions";
62}
63
64pub struct LlmClosedBetaFeatureFlag {}
65impl FeatureFlag for LlmClosedBetaFeatureFlag {
66 const NAME: &'static str = "llm-closed-beta";
67}
68
69pub struct ZedProFeatureFlag {}
70impl FeatureFlag for ZedProFeatureFlag {
71 const NAME: &'static str = "zed-pro";
72}
73
74pub struct NotebookFeatureFlag;
75
76impl FeatureFlag for NotebookFeatureFlag {
77 const NAME: &'static str = "notebooks";
78}
79
80pub struct ThreadAutoCaptureFeatureFlag {}
81impl FeatureFlag for ThreadAutoCaptureFeatureFlag {
82 const NAME: &'static str = "thread-auto-capture";
83
84 fn enabled_for_staff() -> bool {
85 false
86 }
87}
88pub struct PanicFeatureFlag;
89
90impl FeatureFlag for PanicFeatureFlag {
91 const NAME: &'static str = "panic";
92}
93
94pub struct JjUiFeatureFlag {}
95
96impl FeatureFlag for JjUiFeatureFlag {
97 const NAME: &'static str = "jj-ui";
98}
99
100pub struct AcpFeatureFlag;
101
102impl FeatureFlag for AcpFeatureFlag {
103 const NAME: &'static str = "acp";
104}
105
106pub trait FeatureFlagViewExt<V: 'static> {
107 fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
108 where
109 F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static;
110
111 fn when_flag_enabled<T: FeatureFlag>(
112 &mut self,
113 window: &mut Window,
114 callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
115 );
116}
117
118impl<V> FeatureFlagViewExt<V> for Context<'_, V>
119where
120 V: 'static,
121{
122 fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
123 where
124 F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + 'static,
125 {
126 self.observe_global_in::<FeatureFlags>(window, move |v, window, cx| {
127 let feature_flags = cx.global::<FeatureFlags>();
128 callback(feature_flags.has_flag::<T>(), v, window, cx);
129 })
130 }
131
132 fn when_flag_enabled<T: FeatureFlag>(
133 &mut self,
134 window: &mut Window,
135 callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
136 ) {
137 if self
138 .try_global::<FeatureFlags>()
139 .is_some_and(|f| f.has_flag::<T>())
140 {
141 self.defer_in(window, move |view, window, cx| {
142 callback(view, window, cx);
143 });
144 return;
145 }
146 let subscription = Rc::new(RefCell::new(None));
147 let inner = self.observe_global_in::<FeatureFlags>(window, {
148 let subscription = subscription.clone();
149 move |v, window, cx| {
150 let feature_flags = cx.global::<FeatureFlags>();
151 if feature_flags.has_flag::<T>() {
152 callback(v, window, cx);
153 subscription.take();
154 }
155 }
156 });
157 subscription.borrow_mut().replace(inner);
158 }
159}
160
161#[derive(Debug)]
162pub struct OnFlagsReady {
163 pub is_staff: bool,
164}
165
166pub trait FeatureFlagAppExt {
167 fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag;
168
169 /// Waits for the specified feature flag to resolve, up to the given timeout.
170 fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool>;
171
172 fn update_flags(&mut self, staff: bool, flags: Vec<String>);
173 fn set_staff(&mut self, staff: bool);
174 fn has_flag<T: FeatureFlag>(&self) -> bool;
175 fn is_staff(&self) -> bool;
176
177 fn on_flags_ready<F>(&mut self, callback: F) -> Subscription
178 where
179 F: FnMut(OnFlagsReady, &mut App) + 'static;
180
181 fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
182 where
183 F: FnMut(bool, &mut App) + 'static;
184}
185
186impl FeatureFlagAppExt for App {
187 fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
188 let feature_flags = self.default_global::<FeatureFlags>();
189 feature_flags.staff = staff;
190 feature_flags.flags = flags;
191 }
192
193 fn set_staff(&mut self, staff: bool) {
194 let feature_flags = self.default_global::<FeatureFlags>();
195 feature_flags.staff = staff;
196 }
197
198 fn has_flag<T: FeatureFlag>(&self) -> bool {
199 self.try_global::<FeatureFlags>()
200 .map(|flags| flags.has_flag::<T>())
201 .unwrap_or(false)
202 }
203
204 fn is_staff(&self) -> bool {
205 self.try_global::<FeatureFlags>()
206 .map(|flags| flags.staff)
207 .unwrap_or(false)
208 }
209
210 fn on_flags_ready<F>(&mut self, mut callback: F) -> Subscription
211 where
212 F: FnMut(OnFlagsReady, &mut App) + 'static,
213 {
214 self.observe_global::<FeatureFlags>(move |cx| {
215 let feature_flags = cx.global::<FeatureFlags>();
216 callback(
217 OnFlagsReady {
218 is_staff: feature_flags.staff,
219 },
220 cx,
221 );
222 })
223 }
224
225 fn observe_flag<T: FeatureFlag, F>(&mut self, mut callback: F) -> Subscription
226 where
227 F: FnMut(bool, &mut App) + 'static,
228 {
229 self.observe_global::<FeatureFlags>(move |cx| {
230 let feature_flags = cx.global::<FeatureFlags>();
231 callback(feature_flags.has_flag::<T>(), cx);
232 })
233 }
234
235 fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag {
236 let (tx, rx) = oneshot::channel::<bool>();
237 let mut tx = Some(tx);
238 let subscription: Option<Subscription>;
239
240 match self.try_global::<FeatureFlags>() {
241 Some(feature_flags) => {
242 subscription = None;
243 tx.take().unwrap().send(feature_flags.has_flag::<T>()).ok();
244 }
245 None => {
246 subscription = Some(self.observe_global::<FeatureFlags>(move |cx| {
247 let feature_flags = cx.global::<FeatureFlags>();
248 if let Some(tx) = tx.take() {
249 tx.send(feature_flags.has_flag::<T>()).ok();
250 }
251 }));
252 }
253 }
254
255 WaitForFlag(rx, subscription)
256 }
257
258 fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool> {
259 let wait_for_flag = self.wait_for_flag::<T>();
260
261 self.spawn(async move |_cx| {
262 let mut wait_for_flag = wait_for_flag.fuse();
263 let mut timeout = FutureExt::fuse(smol::Timer::after(timeout));
264
265 select_biased! {
266 is_enabled = wait_for_flag => is_enabled,
267 _ = timeout => false,
268 }
269 })
270 }
271}
272
273pub struct WaitForFlag(oneshot::Receiver<bool>, Option<Subscription>);
274
275impl Future for WaitForFlag {
276 type Output = bool;
277
278 fn poll(mut self: Pin<&mut Self>, cx: &mut core::task::Context<'_>) -> Poll<Self::Output> {
279 self.0.poll_unpin(cx).map(|result| {
280 self.1.take();
281 result.unwrap_or(false)
282 })
283 }
284}