feature_flags.rs

  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").is_ok_and(|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 NotebookFeatureFlag;
 70
 71impl FeatureFlag for NotebookFeatureFlag {
 72    const NAME: &'static str = "notebooks";
 73}
 74
 75pub struct PanicFeatureFlag;
 76
 77impl FeatureFlag for PanicFeatureFlag {
 78    const NAME: &'static str = "panic";
 79}
 80
 81pub struct JjUiFeatureFlag {}
 82
 83impl FeatureFlag for JjUiFeatureFlag {
 84    const NAME: &'static str = "jj-ui";
 85}
 86
 87pub struct GeminiAndNativeFeatureFlag;
 88
 89impl FeatureFlag for GeminiAndNativeFeatureFlag {
 90    // This was previously called "acp".
 91    //
 92    // We renamed it because existing builds used it to enable the Claude Code
 93    // integration too, and we'd like to turn Gemini/Native on in new builds
 94    // without enabling Claude Code in old builds.
 95    const NAME: &'static str = "gemini-and-native";
 96
 97    fn enabled_for_all() -> bool {
 98        true
 99    }
100}
101
102pub struct ClaudeCodeFeatureFlag;
103
104impl FeatureFlag for ClaudeCodeFeatureFlag {
105    const NAME: &'static str = "claude-code";
106
107    fn enabled_for_all() -> bool {
108        true
109    }
110}
111
112pub trait FeatureFlagViewExt<V: 'static> {
113    fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
114    where
115        F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static;
116
117    fn when_flag_enabled<T: FeatureFlag>(
118        &mut self,
119        window: &mut Window,
120        callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
121    );
122}
123
124impl<V> FeatureFlagViewExt<V> for Context<'_, V>
125where
126    V: 'static,
127{
128    fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
129    where
130        F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + 'static,
131    {
132        self.observe_global_in::<FeatureFlags>(window, move |v, window, cx| {
133            let feature_flags = cx.global::<FeatureFlags>();
134            callback(feature_flags.has_flag::<T>(), v, window, cx);
135        })
136    }
137
138    fn when_flag_enabled<T: FeatureFlag>(
139        &mut self,
140        window: &mut Window,
141        callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
142    ) {
143        if self
144            .try_global::<FeatureFlags>()
145            .is_some_and(|f| f.has_flag::<T>())
146        {
147            self.defer_in(window, move |view, window, cx| {
148                callback(view, window, cx);
149            });
150            return;
151        }
152        let subscription = Rc::new(RefCell::new(None));
153        let inner = self.observe_global_in::<FeatureFlags>(window, {
154            let subscription = subscription.clone();
155            move |v, window, cx| {
156                let feature_flags = cx.global::<FeatureFlags>();
157                if feature_flags.has_flag::<T>() {
158                    callback(v, window, cx);
159                    subscription.take();
160                }
161            }
162        });
163        subscription.borrow_mut().replace(inner);
164    }
165}
166
167#[derive(Debug)]
168pub struct OnFlagsReady {
169    pub is_staff: bool,
170}
171
172pub trait FeatureFlagAppExt {
173    fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag;
174
175    /// Waits for the specified feature flag to resolve, up to the given timeout.
176    fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool>;
177
178    fn update_flags(&mut self, staff: bool, flags: Vec<String>);
179    fn set_staff(&mut self, staff: bool);
180    fn has_flag<T: FeatureFlag>(&self) -> bool;
181    fn is_staff(&self) -> bool;
182
183    fn on_flags_ready<F>(&mut self, callback: F) -> Subscription
184    where
185        F: FnMut(OnFlagsReady, &mut App) + 'static;
186
187    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
188    where
189        F: FnMut(bool, &mut App) + 'static;
190}
191
192impl FeatureFlagAppExt for App {
193    fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
194        let feature_flags = self.default_global::<FeatureFlags>();
195        feature_flags.staff = staff;
196        feature_flags.flags = flags;
197    }
198
199    fn set_staff(&mut self, staff: bool) {
200        let feature_flags = self.default_global::<FeatureFlags>();
201        feature_flags.staff = staff;
202    }
203
204    fn has_flag<T: FeatureFlag>(&self) -> bool {
205        self.try_global::<FeatureFlags>()
206            .map(|flags| flags.has_flag::<T>())
207            .unwrap_or(T::enabled_for_all())
208    }
209
210    fn is_staff(&self) -> bool {
211        self.try_global::<FeatureFlags>()
212            .map(|flags| flags.staff)
213            .unwrap_or(false)
214    }
215
216    fn on_flags_ready<F>(&mut self, mut callback: F) -> Subscription
217    where
218        F: FnMut(OnFlagsReady, &mut App) + 'static,
219    {
220        self.observe_global::<FeatureFlags>(move |cx| {
221            let feature_flags = cx.global::<FeatureFlags>();
222            callback(
223                OnFlagsReady {
224                    is_staff: feature_flags.staff,
225                },
226                cx,
227            );
228        })
229    }
230
231    fn observe_flag<T: FeatureFlag, F>(&mut self, mut callback: F) -> Subscription
232    where
233        F: FnMut(bool, &mut App) + 'static,
234    {
235        self.observe_global::<FeatureFlags>(move |cx| {
236            let feature_flags = cx.global::<FeatureFlags>();
237            callback(feature_flags.has_flag::<T>(), cx);
238        })
239    }
240
241    fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag {
242        let (tx, rx) = oneshot::channel::<bool>();
243        let mut tx = Some(tx);
244        let subscription: Option<Subscription>;
245
246        match self.try_global::<FeatureFlags>() {
247            Some(feature_flags) => {
248                subscription = None;
249                tx.take().unwrap().send(feature_flags.has_flag::<T>()).ok();
250            }
251            None => {
252                subscription = Some(self.observe_global::<FeatureFlags>(move |cx| {
253                    let feature_flags = cx.global::<FeatureFlags>();
254                    if let Some(tx) = tx.take() {
255                        tx.send(feature_flags.has_flag::<T>()).ok();
256                    }
257                }));
258            }
259        }
260
261        WaitForFlag(rx, subscription)
262    }
263
264    fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool> {
265        let wait_for_flag = self.wait_for_flag::<T>();
266
267        self.spawn(async move |_cx| {
268            let mut wait_for_flag = wait_for_flag.fuse();
269            let mut timeout = FutureExt::fuse(smol::Timer::after(timeout));
270
271            select_biased! {
272                is_enabled = wait_for_flag => is_enabled,
273                _ = timeout => false,
274            }
275        })
276    }
277}
278
279pub struct WaitForFlag(oneshot::Receiver<bool>, Option<Subscription>);
280
281impl Future for WaitForFlag {
282    type Output = bool;
283
284    fn poll(mut self: Pin<&mut Self>, cx: &mut core::task::Context<'_>) -> Poll<Self::Output> {
285        self.0.poll_unpin(cx).map(|result| {
286            self.1.take();
287            result.unwrap_or(false)
288        })
289    }
290}