From c61f1d20ea14c3e5f9b280b5983612d55eab1504 Mon Sep 17 00:00:00 2001
From: Noah <33094578+coolreader18@users.noreply.github.com>
Date: Mon, 26 Aug 2019 21:21:31 +0000
Subject: [PATCH] Allow time.time() to work on WASM

---
 Cargo.lock                   |  1 +
 vm/Cargo.toml                |  3 +++
 vm/src/stdlib/time_module.rs | 41 +++++++++++++++++++++---------------
 3 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 1fa7a64e2..9af305125 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1210,6 +1210,7 @@ dependencies = [
  "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode_categories 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode_names2 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasm-bindgen 0.2.50 (registry+https://github.com/rust-lang/crates.io-index)",
  "wtf8 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
diff --git a/vm/Cargo.toml b/vm/Cargo.toml
index b11abadb7..9b702e4d4 100644
--- a/vm/Cargo.toml
+++ b/vm/Cargo.toml
@@ -83,3 +83,6 @@ num_cpus = "1.0"
 
 [target."cfg(windows)".dependencies]
 kernel32-sys = "0.2.2"
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+wasm-bindgen = "0.2"
diff --git a/vm/src/stdlib/time_module.rs b/vm/src/stdlib/time_module.rs
index 5d7205489..f5d196b84 100644
--- a/vm/src/stdlib/time_module.rs
+++ b/vm/src/stdlib/time_module.rs
@@ -5,7 +5,7 @@ use std::fmt;
 use std::ops::Range;
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
-use crate::function::{OptionalArg, PyFuncArgs};
+use crate::function::OptionalArg;
 use crate::obj::objfloat::PyFloatRef;
 use crate::obj::objint::PyInt;
 use crate::obj::objsequence::get_sequence_index;
@@ -44,38 +44,45 @@ fn time_sleep(seconds: PyFloatRef, vm: &VirtualMachine) -> PyResult<()> {
 }
 
 #[cfg(not(unix))]
-fn time_sleep(seconds: PyFloatRef, vm: &VirtualMachine) -> PyResult<()> {
+fn time_sleep(seconds: PyFloatRef, _vm: &VirtualMachine) {
     let seconds = seconds.to_f64();
     let secs: u64 = seconds.trunc() as u64;
     let nanos: u32 = (seconds.fract() * 1e9) as u32;
     let duration = Duration::new(secs, nanos);
     std::thread::sleep(duration);
-    Ok(())
 }
 
 fn duration_to_f64(d: Duration) -> f64 {
     (d.as_secs() as f64) + (f64::from(d.subsec_nanos()) / 1e9)
 }
 
-fn time_time(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
-    arg_check!(vm, args);
-    let x = match SystemTime::now().duration_since(UNIX_EPOCH) {
+#[cfg(not(target_arch = "wasm32"))]
+fn time_time(_vm: &VirtualMachine) -> f64 {
+    match SystemTime::now().duration_since(UNIX_EPOCH) {
         Ok(v) => duration_to_f64(v),
-        Err(err) => panic!("Error: {:?}", err),
-    };
-    let value = vm.ctx.new_float(x);
-    Ok(value)
+        Err(err) => panic!("Time error: {:?}", err),
+    }
 }
 
-fn time_monotonic(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
-    arg_check!(vm, args);
+#[cfg(target_arch = "wasm32")]
+fn time_time(_vm: &VirtualMachine) -> f64 {
+    use wasm_bindgen::prelude::*;
+    #[wasm_bindgen]
+    extern "C" {
+        type Date;
+        #[wasm_bindgen(static_method_of = Date)]
+        fn now() -> f64;
+    }
+    // Date.now returns unix time in milliseconds, we want it in seconds
+    Date::now() / 1000.0
+}
+
+fn time_monotonic(_vm: &VirtualMachine) -> f64 {
     // TODO: implement proper monotonic time!
-    let x = match SystemTime::now().duration_since(UNIX_EPOCH) {
+    match SystemTime::now().duration_since(UNIX_EPOCH) {
         Ok(v) => duration_to_f64(v),
-        Err(err) => panic!("Error: {:?}", err),
-    };
-    let value = vm.ctx.new_float(x);
-    Ok(value)
+        Err(err) => panic!("Time error: {:?}", err),
+    }
 }
 
 fn pyfloat_to_secs_and_nanos(seconds: &PyObjectRef) -> (i64, u32) {