3 files changed, 153 insertions, 0 deletions
diff --git a/crates/web-time-compat/src/lib.rs b/crates/web-time-compat/src/lib.rs
new file mode 100644
index 000000000..31abd17f5
--- /dev/null
+++ b/crates/web-time-compat/src/lib.rs
@@ -0,0 +1,112 @@
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![doc = include_str!("../README.md")]
+// @@ begin lint list maintained by maint/add_warning @@
+#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)
+#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)
+#![warn(missing_docs)]
+#![warn(noop_method_call)]
+#![warn(unreachable_pub)]
+#![warn(clippy::all)]
+#![deny(clippy::await_holding_lock)]
+#![deny(clippy::cargo_common_metadata)]
+#![deny(clippy::cast_lossless)]
+#![deny(clippy::checked_conversions)]
+#![warn(clippy::cognitive_complexity)]
+#![deny(clippy::debug_assert_with_mut_call)]
+#![deny(clippy::exhaustive_enums)]
+#![deny(clippy::exhaustive_structs)]
+#![deny(clippy::expl_impl_clone_on_copy)]
+#![deny(clippy::fallible_impl_from)]
+#![deny(clippy::implicit_clone)]
+#![deny(clippy::large_stack_arrays)]
+#![warn(clippy::manual_ok_or)]
+#![deny(clippy::missing_docs_in_private_items)]
+#![warn(clippy::needless_borrow)]
+#![warn(clippy::needless_pass_by_value)]
+#![warn(clippy::option_option)]
+#![deny(clippy::print_stderr)]
+#![deny(clippy::print_stdout)]
+#![warn(clippy::rc_buffer)]
+#![deny(clippy::ref_option_ref)]
+#![warn(clippy::semicolon_if_nothing_returned)]
+#![warn(clippy::trait_duplication_in_bounds)]
+#![deny(clippy::unchecked_time_subtraction)]
+#![deny(clippy::unnecessary_wraps)]
+#![warn(clippy::unseparated_literal_suffix)]
+#![deny(clippy::unwrap_used)]
+#![deny(clippy::mod_module_files)]
+#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness
+#![allow(clippy::uninlined_format_args)]
+#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945
+#![allow(clippy::result_large_err)] // temporary workaround for arti#587
+#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best
+#![allow(clippy::needless_lifetimes)] // See arti#1765
+#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060
+#![allow(clippy::collapsible_if)] // See arti#2342
+#![deny(clippy::unused_async)]
+//! <!-- @@ end lint list maintained by maint/add_warning @@ -->
+
+// We always use `SystemTime` for our data representation outside of this crate.
+//
+// The only time that we touch `SystemTime` is when we are constructing it with
+// `SystemTimeExt::get`.
+pub use std::time::SystemTime;
+
+// "Duration" is the same type in web_time as it is in stdlib.
+pub use std::time::Duration;
+
+#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
+mod stdlib;
+
+#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
+pub use stdlib::*;
+
+#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+mod wasm;
+
+#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+pub use wasm::*;
+
+/// Module to hide "Sealed"
+mod seal {
+    /// Trait used to prevent implementing InstantExt or SystemTimeExt outside of this crate.
+    #[allow(unreachable_pub)]
+    pub trait Sealed {}
+}
+
+/// Extension trait for [`std::time::SystemTime`]
+///
+/// This trait adds a `get` method which works like `now`,
+/// but also supports `wasm32-unknown-unknown` environments.
+pub trait SystemTimeExt: seal::Sealed {
+    /// Return the current time.
+    fn get() -> std::time::SystemTime;
+}
+
+/// Extension trait for [`Instant`].
+///
+/// This trait adds a `get` method which works like `now`,
+/// so we can make sure we aren't calling [`std::time::Instant::now`]
+/// on`wasm32-unknown-unknown` environments.
+///
+/// ## Design note
+///
+/// Since we already replace the `std::time::Instant` type with
+/// `web_time::Instant` in this crate, why do we also provide
+/// an extension trait to rename its "now" method?
+///
+/// We do so for two reasons:
+///
+/// 1. Consistency.  With this approach, you don't have to remember
+///    which type uses `get` and which uses `now`.
+/// 2. Enforcement.  This approach makes it possible to use Clippy
+///    to disallow `std::time::Instant::now()` unconditionally,
+///    to make sure that you don't forget to use
+///    the appropriate `web_time_compat::Instant` type instead.
+pub trait InstantExt: seal::Sealed {
+    /// Return the current time.
+    fn get() -> crate::Instant;
+}
+
+impl seal::Sealed for std::time::SystemTime {}
+impl seal::Sealed for crate::Instant {}
diff --git a/crates/web-time-compat/src/stdlib.rs b/crates/web-time-compat/src/stdlib.rs
new file mode 100644
index 000000000..891a0e0f7
--- /dev/null
+++ b/crates/web-time-compat/src/stdlib.rs
@@ -0,0 +1,21 @@
+//! Standard-library time functionality..
+
+// If we've forbidden `now` elsewhere in our project, we enable it here.
+// (And only here!)
+#![allow(clippy::disallowed_methods)]
+
+pub use std::time::Instant;
+
+use std::time::SystemTime;
+
+impl crate::SystemTimeExt for SystemTime {
+    fn get() -> SystemTime {
+        SystemTime::now()
+    }
+}
+
+impl crate::InstantExt for Instant {
+    fn get() -> crate::Instant {
+        Instant::now()
+    }
+}
diff --git a/crates/web-time-compat/src/wasm.rs b/crates/web-time-compat/src/wasm.rs
new file mode 100644
index 000000000..37d2198ce
--- /dev/null
+++ b/crates/web-time-compat/src/wasm.rs
@@ -0,0 +1,20 @@
+//! Wasm-specific time functionality.
+
+// If we've forbidden `now` elsewhere in our project, we enable it here.
+#![allow(clippy::disallowed_methods)]
+
+pub use web_time::Instant;
+
+impl crate::SystemTimeExt for std::time::SystemTime {
+    fn get() -> std::time::SystemTime {
+        use web_time::web::SystemTimeExt as _;
+        let now = web_time::SystemTime::now();
+        now.to_std()
+    }
+}
+
+impl crate::InstantExt for Instant {
+    fn get() -> crate::Instant {
+        Instant::now()
+    }
+}