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 (cfg!(debug_assertions) || self.staff) && !*ZED_DISABLE_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 BillingV2FeatureFlag {}
 65
 66impl FeatureFlag for BillingV2FeatureFlag {
 67    const NAME: &'static str = "billing-v2";
 68}
 69
 70pub struct NotebookFeatureFlag;
 71
 72impl FeatureFlag for NotebookFeatureFlag {
 73    const NAME: &'static str = "notebooks";
 74}
 75
 76pub struct PanicFeatureFlag;
 77
 78impl FeatureFlag for PanicFeatureFlag {
 79    const NAME: &'static str = "panic";
 80}
 81
 82pub struct JjUiFeatureFlag {}
 83
 84impl FeatureFlag for JjUiFeatureFlag {
 85    const NAME: &'static str = "jj-ui";
 86}
 87
 88pub struct GeminiAndNativeFeatureFlag;
 89
 90impl FeatureFlag for GeminiAndNativeFeatureFlag {
 91    // This was previously called "acp".
 92    //
 93    // We renamed it because existing builds used it to enable the Claude Code
 94    // integration too, and we'd like to turn Gemini/Native on in new builds
 95    // without enabling Claude Code in old builds.
 96    const NAME: &'static str = "gemini-and-native";
 97
 98    fn enabled_for_all() -> bool {
 99        true
100    }
101}
102
103pub struct ClaudeCodeFeatureFlag;
104
105impl FeatureFlag for ClaudeCodeFeatureFlag {
106    const NAME: &'static str = "claude-code";
107
108    fn enabled_for_all() -> bool {
109        true
110    }
111}
112
113pub trait FeatureFlagViewExt<V: 'static> {
114    fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
115    where
116        F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static;
117
118    fn when_flag_enabled<T: FeatureFlag>(
119        &mut self,
120        window: &mut Window,
121        callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
122    );
123}
124
125impl<V> FeatureFlagViewExt<V> for Context<'_, V>
126where
127    V: 'static,
128{
129    fn observe_flag<T: FeatureFlag, F>(&mut self, window: &Window, callback: F) -> Subscription
130    where
131        F: Fn(bool, &mut V, &mut Window, &mut Context<V>) + 'static,
132    {
133        self.observe_global_in::<FeatureFlags>(window, move |v, window, cx| {
134            let feature_flags = cx.global::<FeatureFlags>();
135            callback(feature_flags.has_flag::<T>(), v, window, cx);
136        })
137    }
138
139    fn when_flag_enabled<T: FeatureFlag>(
140        &mut self,
141        window: &mut Window,
142        callback: impl Fn(&mut V, &mut Window, &mut Context<V>) + Send + Sync + 'static,
143    ) {
144        if self
145            .try_global::<FeatureFlags>()
146            .is_some_and(|f| f.has_flag::<T>())
147        {
148            self.defer_in(window, move |view, window, cx| {
149                callback(view, window, cx);
150            });
151            return;
152        }
153        let subscription = Rc::new(RefCell::new(None));
154        let inner = self.observe_global_in::<FeatureFlags>(window, {
155            let subscription = subscription.clone();
156            move |v, window, cx| {
157                let feature_flags = cx.global::<FeatureFlags>();
158                if feature_flags.has_flag::<T>() {
159                    callback(v, window, cx);
160                    subscription.take();
161                }
162            }
163        });
164        subscription.borrow_mut().replace(inner);
165    }
166}
167
168#[derive(Debug)]
169pub struct OnFlagsReady {
170    pub is_staff: bool,
171}
172
173pub trait FeatureFlagAppExt {
174    fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag;
175
176    /// Waits for the specified feature flag to resolve, up to the given timeout.
177    fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool>;
178
179    fn update_flags(&mut self, staff: bool, flags: Vec<String>);
180    fn set_staff(&mut self, staff: bool);
181    fn has_flag<T: FeatureFlag>(&self) -> bool;
182    fn is_staff(&self) -> bool;
183
184    fn on_flags_ready<F>(&mut self, callback: F) -> Subscription
185    where
186        F: FnMut(OnFlagsReady, &mut App) + 'static;
187
188    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
189    where
190        F: FnMut(bool, &mut App) + 'static;
191}
192
193impl FeatureFlagAppExt for App {
194    fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
195        let feature_flags = self.default_global::<FeatureFlags>();
196        feature_flags.staff = staff;
197        feature_flags.flags = flags;
198    }
199
200    fn set_staff(&mut self, staff: bool) {
201        let feature_flags = self.default_global::<FeatureFlags>();
202        feature_flags.staff = staff;
203    }
204
205    fn has_flag<T: FeatureFlag>(&self) -> bool {
206        self.try_global::<FeatureFlags>()
207            .map(|flags| flags.has_flag::<T>())
208            .unwrap_or_else(|| {
209                (cfg!(debug_assertions) && T::enabled_for_staff() && !*ZED_DISABLE_STAFF)
210                    || T::enabled_for_all()
211            })
212    }
213
214    fn is_staff(&self) -> bool {
215        self.try_global::<FeatureFlags>()
216            .map(|flags| flags.staff)
217            .unwrap_or(false)
218    }
219
220    fn on_flags_ready<F>(&mut self, mut callback: F) -> Subscription
221    where
222        F: FnMut(OnFlagsReady, &mut App) + 'static,
223    {
224        self.observe_global::<FeatureFlags>(move |cx| {
225            let feature_flags = cx.global::<FeatureFlags>();
226            callback(
227                OnFlagsReady {
228                    is_staff: feature_flags.staff,
229                },
230                cx,
231            );
232        })
233    }
234
235    fn observe_flag<T: FeatureFlag, F>(&mut self, mut callback: F) -> Subscription
236    where
237        F: FnMut(bool, &mut App) + 'static,
238    {
239        self.observe_global::<FeatureFlags>(move |cx| {
240            let feature_flags = cx.global::<FeatureFlags>();
241            callback(feature_flags.has_flag::<T>(), cx);
242        })
243    }
244
245    fn wait_for_flag<T: FeatureFlag>(&mut self) -> WaitForFlag {
246        let (tx, rx) = oneshot::channel::<bool>();
247        let mut tx = Some(tx);
248        let subscription: Option<Subscription>;
249
250        match self.try_global::<FeatureFlags>() {
251            Some(feature_flags) => {
252                subscription = None;
253                tx.take().unwrap().send(feature_flags.has_flag::<T>()).ok();
254            }
255            None => {
256                subscription = Some(self.observe_global::<FeatureFlags>(move |cx| {
257                    let feature_flags = cx.global::<FeatureFlags>();
258                    if let Some(tx) = tx.take() {
259                        tx.send(feature_flags.has_flag::<T>()).ok();
260                    }
261                }));
262            }
263        }
264
265        WaitForFlag(rx, subscription)
266    }
267
268    fn wait_for_flag_or_timeout<T: FeatureFlag>(&mut self, timeout: Duration) -> Task<bool> {
269        let wait_for_flag = self.wait_for_flag::<T>();
270
271        self.spawn(async move |_cx| {
272            let mut wait_for_flag = wait_for_flag.fuse();
273            let mut timeout = FutureExt::fuse(smol::Timer::after(timeout));
274
275            select_biased! {
276                is_enabled = wait_for_flag => is_enabled,
277                _ = timeout => false,
278            }
279        })
280    }
281}
282
283pub struct WaitForFlag(oneshot::Receiver<bool>, Option<Subscription>);
284
285impl Future for WaitForFlag {
286    type Output = bool;
287
288    fn poll(mut self: Pin<&mut Self>, cx: &mut core::task::Context<'_>) -> Poll<Self::Output> {
289        self.0.poll_unpin(cx).map(|result| {
290            self.1.take();
291            result.unwrap_or(false)
292        })
293    }
294}