Merge pull request #446 from schrieveslaach/feature/js-sys-date-improvements

Improve From<js_sys::Date> Variants for DateTime<Utc>

CHANGELOG.md

@@ -14,6 +14,11 @@ Versions with only mechanical changes will be omitted from the following list.
 
 * Add `DurationRound` trait that allows rounding and truncating by `Duration` (@robyoung)
 
+### Internal Improvements
+
+* Code improvements to impl `From` for `js_sys` in wasm to reuse code (@schrieveslaach)
+
+
 ## 0.4.12
 
 ### New Methods and impls

Cargo.toml

@@ -52,7 +52,7 @@ criterion = { version = "0.3" }
 doc-comment = { version = "0.3" }
 
 [target.'cfg(all(target_arch = "wasm32", not(any(target_os = "emscripten", target_os = "wasi"))))'.dev-dependencies]
-wasm-bindgen-test = "0.2"
+wasm-bindgen-test = "0.3"
 
 [package.metadata.docs.rs]
 features = ["serde"]

ci/github.sh

@@ -91,9 +91,8 @@ test_wasm() {
 
 test_wasm_simple() {
     now=$(date +%s)
-    for tz in "${TEST_TZS[@]}"; do
-        runt env TZ="$tz" NOW="$now" wasm-pack test --node -- --features wasmbind
-    done
+    tz=$(date +%z)
+    runt env TZ="$tz" NOW="$now" wasm-pack test --node -- --features wasmbind
 }
 
 main "$@"

src/datetime.rs

@@ -753,22 +753,18 @@ impl<Tz: TimeZone> From<DateTime<Tz>> for SystemTime {
 #[cfg(all(target_arch = "wasm32", not(target_os = "wasi"), feature = "wasmbind"))]
 impl From<js_sys::Date> for DateTime<Utc> {
     fn from(date: js_sys::Date) -> DateTime<Utc> {
-        let time = date.get_time() as i64;
-        DateTime::<Utc>::from_utc(
-            NaiveDateTime::from_timestamp(time / 1000, ((time % 1000) * 1_000_000) as u32),
-            Utc,
-        )
+        DateTime::<Utc>::from(&date)
     }
 }
 
 #[cfg(all(target_arch = "wasm32", not(target_os = "wasi"), feature = "wasmbind"))]
 impl From<&js_sys::Date> for DateTime<Utc> {
     fn from(date: &js_sys::Date) -> DateTime<Utc> {
-        let time = date.get_time() as i64;
-        DateTime::<Utc>::from_utc(
-            NaiveDateTime::from_timestamp(time / 1000, ((time % 1000) * 1_000_000) as u32),
-            Utc,
-        )
+        let millisecs_since_unix_epoch: u64 = date.get_time() as u64;
+        let secs = millisecs_since_unix_epoch / 1000;
+        let nanos = 1_000_000 * (millisecs_since_unix_epoch % 1000);
+        let naive = NaiveDateTime::from_timestamp(secs as i64, nanos as u32);
+        DateTime::from_utc(naive, Utc)
     }
 }
 

src/offset/utc.rs

@@ -54,11 +54,7 @@ impl Utc {
     #[cfg(all(target_arch = "wasm32", not(target_os = "wasi"), feature = "wasmbind"))]
     pub fn now() -> DateTime<Utc> {
         let now = js_sys::Date::new_0();
-        let millisecs_since_unix_epoch: u64 = now.get_time() as u64;
-        let secs = millisecs_since_unix_epoch / 1000;
-        let nanos = 1_000_000 * (millisecs_since_unix_epoch - 1000 * secs);
-        let naive = NaiveDateTime::from_timestamp(secs as i64, nanos as u32);
-        DateTime::from_utc(naive, Utc)
+        DateTime::<Utc>::from(now)
     }
 }
 

tests/wasm.rs

@@ -12,17 +12,36 @@ mod test {
         let local: DateTime<Local> = Local::now();
 
         // Ensure time fetched is correct
-        let actual = Utc.datetime_from_str(env!("NOW"), "%s").unwrap();
+        let actual = Utc.datetime_from_str(&env!("NOW"), "%s").unwrap();
         assert!(utc - actual < chrono::Duration::minutes(5));
 
+        let tz = env!("TZ");
+        eprintln!("testing with tz={}", tz);
+
         // Ensure offset retrieved when getting local time is correct
-        let expected_offset = match env!("TZ") {
+        let expected_offset = match tz {
             "ACST-9:30" => FixedOffset::east(19 * 30 * 60),
             "Asia/Katmandu" => FixedOffset::east(23 * 15 * 60), // No DST thankfully
-            "EST4" => FixedOffset::east(-4 * 60 * 60),
-            "UTC0" => FixedOffset::east(0),
-            _ => panic!("unexpected TZ"),
+            "EDT" | "EST4" | "-0400" => FixedOffset::east(-4 * 60 * 60),
+            "EST" | "-0500" => FixedOffset::east(-5 * 60 * 60),
+            "UTC0" | "+0000" => FixedOffset::east(0),
+            tz => panic!("unexpected TZ {}", tz),
         };
-        assert_eq!(&expected_offset, local.offset());
+        assert_eq!(
+            &expected_offset,
+            local.offset(),
+            "expected: {:?} local: {:?}",
+            expected_offset,
+            local.offset(),
+        );
+    }
+
+    #[wasm_bindgen_test]
+    fn from_is_exact() {
+        let now = js_sys::Date::new_0();
+
+        let dt = DateTime::<Utc>::from(now.clone());
+
+        assert_eq!(now.get_time() as i64, dt.timestamp_millis());
     }
 }