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}
88
89pub struct JjUiFeatureFlag {}
90
91impl FeatureFlag for JjUiFeatureFlag {
92 const NAME: &'static str = "jj-ui";
93}
94
95pub struct AcpFeatureFlag;
96
97impl FeatureFlag for AcpFeatureFlag {
98 const NAME: &'static str = "acp";
99}
100
101pub trait FeatureFlagViewExt<V: 'static> {
102 fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
103 where
104 F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static;
105
106 fn when_flag_enabled<T: FeatureFlag>(
107 &mut self,
108 window: &mut Window,
109 callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
110 );
111}
112
113impl<V> FeatureFlagViewExt<V> for Context<'_, V>
114where
115 V: 'static,
116{
117 fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
118 where
119 F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + 'static,
120 {
121 self.observe_global_in::<FeatureFlags>(window, move |v, window, cx| {
122 let feature_flags = cx.global::<FeatureFlags>();
123 callback(feature_flags.has_flag::<T>(), v, window, cx);
124 })
125 }
126
127 fn when_flag_enabled<T: FeatureFlag>(
128 &mut self,
129 window: &mut Window,
130 callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
131 ) {
132 if self
133 .try_global::<FeatureFlags>()
134 .is_some_and(|f| f.has_flag::<T>())
135 {
136 self.defer_in(window, move |view, window, cx| {
137 callback(view, window, cx);
138 });
139 return;
140 }
141 let subscription = Rc::new(RefCell::new(None));
142 let inner = self.observe_global_in::<FeatureFlags>(window, {
143 let subscription = subscription.clone();
144 move |v, window, cx| {
145 let feature_flags = cx.global::<FeatureFlags>();
146 if feature_flags.has_flag::<T>() {
147 callback(v, window, cx);
148 subscription.take();
149 }
150 }
151 });
152 subscription.borrow_mut().replace(inner);
153 }
154}
155
156pub trait FeatureFlagAppExt {
157 fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag;
158
159 /// Waits for the specified feature flag to resolve, up to the given timeout.
160 fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool>;
161
162 fn update_flags(&mut self, staff: bool, flags: Vec<String>);
163 fn set_staff(&mut self, staff: bool);
164 fn has_flag<T: FeatureFlag>(&self) -> bool;
165 fn is_staff(&self) -> bool;
166
167 fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
168 where
169 F: FnMut(bool, &mut App) + 'static;
170}
171
172impl FeatureFlagAppExt for App {
173 fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
174 let feature_flags = self.default_global::<FeatureFlags>();
175 feature_flags.staff = staff;
176 feature_flags.flags = flags;
177 }
178
179 fn set_staff(&mut self, staff: bool) {
180 let feature_flags = self.default_global::<FeatureFlags>();
181 feature_flags.staff = staff;
182 }
183
184 fn has_flag<T: FeatureFlag>(&self) -> bool {
185 self.try_global::<FeatureFlags>()
186 .map(|flags| flags.has_flag::<T>())
187 .unwrap_or(false)
188 }
189
190 fn is_staff(&self) -> bool {
191 self.try_global::<FeatureFlags>()
192 .map(|flags| flags.staff)
193 .unwrap_or(false)
194 }
195
196 fn observe_flag<T: FeatureFlag, F>(&mut self, mut callback: F) -> Subscription
197 where
198 F: FnMut(bool, &mut App) + 'static,
199 {
200 self.observe_global::<FeatureFlags>(move |cx| {
201 let feature_flags = cx.global::<FeatureFlags>();
202 callback(feature_flags.has_flag::<T>(), cx);
203 })
204 }
205
206 fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag {
207 let (tx, rx) = oneshot::channel::<bool>();
208 let mut tx = Some(tx);
209 let subscription: Option<Subscription>;
210
211 match self.try_global::<FeatureFlags>() {
212 Some(feature_flags) => {
213 subscription = None;
214 tx.take().unwrap().send(feature_flags.has_flag::<T>()).ok();
215 }
216 None => {
217 subscription = Some(self.observe_global::<FeatureFlags>(move |cx| {
218 let feature_flags = cx.global::<FeatureFlags>();
219 if let Some(tx) = tx.take() {
220 tx.send(feature_flags.has_flag::<T>()).ok();
221 }
222 }));
223 }
224 }
225
226 WaitForFlag(rx, subscription)
227 }
228
229 fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool> {
230 let wait_for_flag = self.wait_for_flag::<T>();
231
232 self.spawn(async move |_cx| {
233 let mut wait_for_flag = wait_for_flag.fuse();
234 let mut timeout = FutureExt::fuse(smol::Timer::after(timeout));
235
236 select_biased! {
237 is_enabled = wait_for_flag => is_enabled,
238 _ = timeout => false,
239 }
240 })
241 }
242}
243
244pub struct WaitForFlag(oneshot::Receiver<bool>, Option<Subscription>);
245
246impl Future for WaitForFlag {
247 type Output = bool;
248
249 fn poll(mut self: Pin<&mut Self>, cx: &mut core::task::Context<'_>) -> Poll<Self::Output> {
250 self.0.poll_unpin(cx).map(|result| {
251 self.1.take();
252 result.unwrap_or(false)
253 })
254 }
255}