Try #35:

.circleci/config.yml

@@ -1,4 +1,6 @@
 version: "2.1"
+orbs:
+  browser-tools: circleci/[email protected]
 
 executors: {
   "beta": {
@@ -37,6 +39,29 @@ commands:
       - run:
           name: Test
           command: cargo test --verbose --all
+  wasm_pack_install:
+    description: "Installs `wasm-pack`"
+    steps:
+      # We need to install a custom build of wasm-pack as it doesn't pass through parameters to cargo correctly:
+      # <https://github.com/rustwasm/wasm-pack/pull/851>
+      # - run:
+      #     name: "Install wasm-pack"
+      #     command: curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh
+      - run:
+          name: "Install wasm-pack"
+          command: cargo install --git https://github.com/azriel91/wasm-pack.git --branch bugfix/698/build-tests-with-passthrough-args --force
+      - run:
+          name: "Print wasm-pack version"
+          command: "wasm-pack --version"
+  wasm_pack_test:
+    description: "Runs WASM Tests"
+    parameters:
+      browser:
+        type: string
+    steps:
+      - run:
+          name: "Test With Browser (<< parameters.browser >>)"
+          command: wasm-pack test --headless --<< parameters.browser >> -- --no-default-features --features "std wasm-bindgen"
 
 jobs:
   test:
@@ -52,6 +77,23 @@ jobs:
       - checkout
       - cargo_test
 
+  wasm_test:
+    parameters:
+      version:
+        type: executor
+      version_name:
+        type: string
+      browser:
+        type: string
+    executor: << parameters.version >>
+    environment:
+      CI_RUST_VERSION: << parameters.version_name >>
+    steps:
+      - browser-tools/install-browser-tools
+      - checkout
+      - wasm_pack_install
+      - wasm_pack_test: { browser: << parameters.browser >> }
+
   rustfmt:
     parameters:
       version:
@@ -153,6 +195,40 @@ workflows:
       "/^v\\d+\\.\\d+\\.\\d+.*$/"
     ]
   }
+}
+      - wasm_test:
+          name: wasm_test-chrome
+          version: stable
+          version_name: stable
+          browser: chrome
+          filters: {
+  "branches": {
+    "ignore": [
+      "/.*\\.tmp/"
+    ]
+  },
+  "tags": {
+    "only": [
+      "/^v\\d+\\.\\d+\\.\\d+.*$/"
+    ]
+  }
+}
+      - wasm_test:
+          name: wasm_test-firefox
+          version: stable
+          version_name: stable
+          browser: firefox
+          filters: {
+  "branches": {
+    "ignore": [
+      "/.*\\.tmp/"
+    ]
+  },
+  "tags": {
+    "only": [
+      "/^v\\d+\\.\\d+\\.\\d+.*$/"
+    ]
+  }
 }
       - rustfmt:
           version: stable

CHANGELOG.md

@@ -4,6 +4,16 @@
 
 ## [Unreleased] - ReleaseDate
 
+### Added
+
+* Support for the `wasm32-unknown-unknown` target. Default features have to be
+  disabled so that native dependencies are not built, and `Jitter` is not
+  available.
+
+### Contributors
+
+* [@azriel91](https://github.com/azriel91)
+
 ## [[0.3.1](https://docs.rs/governor/0.3.1/governor/)] - 2020-07-26
 
 ### Added

Cargo.toml

@@ -15,6 +15,9 @@ keywords = ["rate-limiting", "rate-limit", "no_std", "gcra"]
 # We use criterion, don't infer benchmark files.
 autobenches = false
 
+[lib]
+crate-type = ["cdylib", "rlib"]
+
 [package.metadata.template_ci.bench]
 run = true
 version = "nightly"
@@ -44,26 +47,34 @@ name = "governor_criterion_benches"
 harness = false
 
 [dev-dependencies]
+crossbeam = "0.7.3"
+more-asserts = "0.2.1"
+
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
 criterion = "0.3.2"
 tynm = "0.1.4"
-crossbeam = "0.7.3"
 libc = "0.2.70"
 futures = "0.3.5"
 proptest = "0.10.0"
-more-asserts = "0.2.1"
 
 [features]
 default = ["std", "dashmap", "jitter", "quanta"]
 std = ["no-std-compat/std", "nonzero_ext/std", "futures-timer", "futures"]
 jitter = ["rand"]
+stdweb = ["instant/stdweb"]
+wasm-bindgen = ["futures-timer/wasm-bindgen", "instant/wasm-bindgen"]
 no_std = []
 
 [dependencies]
 nonzero_ext = { version = "0.2.0", default-features = false }
 parking_lot = "0.11.0"
 futures-timer = { version = "3.0.2", optional = true }
 futures = { version = "0.3.5", optional = true }
+instant = "0.1.7"
 rand = { version = "0.7.3", optional = true }
 dashmap = { version = "3.11.1", optional = true }
 quanta = { version = "0.4.1", optional = true }
 no-std-compat = { version = "0.4.0", features = [ "alloc", "compat_hash" ] }
+
+[target.'cfg(target_arch = "wasm32")'.dev-dependencies]
+wasm-bindgen-test = "0.3.12"

benches/multi_threaded.rs

@@ -5,10 +5,11 @@
 use criterion::{black_box, BenchmarkId, Criterion, Throughput};
 use governor::state::keyed::{DashMapStateStore, HashMapStateStore, KeyedStateStore};
 use governor::{clock, Quota, RateLimiter};
+use instant::Instant;
 use nonzero_ext::*;
 use std::sync::Arc;
 use std::thread;
-use std::time::{Duration, Instant};
+use std::time::Duration;
 use tynm::type_name;
 
 pub fn bench_all(c: &mut Criterion) {

src/clock/default.rs

@@ -1,5 +1,5 @@
 #[cfg(all(feature = "std", not(feature = "quanta")))]
-/// The default clock that reports [`Instant`][std::time::Instant]s.
+/// The default clock that reports [`Instant`][instant::Instant]s.
 pub type DefaultClock = crate::clock::MonotonicClock;
 
 #[cfg(all(feature = "std", feature = "quanta"))]

src/clock/with_std.rs

@@ -3,8 +3,9 @@ use super::{Clock, Reference};
 use std::prelude::v1::*;
 
 use crate::nanos::Nanos;
+use instant::Instant;
 use std::ops::Add;
-use std::time::{Duration, Instant, SystemTime};
+use std::time::{Duration, SystemTime};
 
 /// The monotonic clock implemented by [`Instant`].
 #[derive(Clone, Debug, Default)]

src/jitter.rs

@@ -11,7 +11,7 @@ use std::ops::Add;
 use std::time::Duration;
 
 #[cfg(feature = "std")]
-use std::time::Instant;
+use instant::Instant;
 
 /// An interval specification for deviating from the nominal wait time.
 ///

src/lib.rs

@@ -49,7 +49,7 @@ pub use errors::*;
 pub use gcra::NotUntil;
 #[cfg(feature = "jitter")]
 pub use jitter::Jitter;
-#[cfg(all(not(feature = "std"), feature = "jitter"))]
+#[cfg(all(not(feature = "jitter"), feature = "std"))]
 pub(crate) use jitter::Jitter;
 pub use quota::Quota;
 #[doc(inline)]

tests/direct.rs

@@ -5,6 +5,14 @@ use governor::{
 use nonzero_ext::nonzero;
 use std::time::Duration;
 
+// Trick so we don't have to annotate each test with:
+// #[cfg_attr(target_arch = "wasm32", wasm_bindgen_test)]
+#[cfg(target_arch = "wasm32")]
+use wasm_bindgen_test::wasm_bindgen_test as test;
+
+#[cfg(target_arch = "wasm32")]
+wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
+
 #[test]
 fn accepts_first_cell() {
     let clock = FakeRelativeClock::default();
@@ -141,6 +149,8 @@ fn correct_wait_time() {
     assert_eq!(20, conforming);
 }
 
+// Crossbeam scoped threads are not supported on WASM
+#[cfg(not(target_arch = "wasm32"))]
 #[test]
 fn actual_threadsafety() {
     use crossbeam;