B1: add update() to the 12 Node candle indicators

Stochastic, OBV, ADX, CCI, WilliamsR, MFI, PSAR, Keltner, Donchian,
VWAP, AwesomeOscillator and Aroon previously exposed only batch() in the
Node binding, so a streaming-first library could not actually stream
them from Node. Each now has an update() mirroring the AtrNode pattern,
with the same input arity and output type as its batch() counterpart.
Verified against the rebuilt native module.

bindings/node/src/lib.rs

@@ -289,6 +289,18 @@ impl StochNode {
         }
     }
     #[napi]
+    pub fn update(
+        &mut self,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<StochValue>> {
+        Ok(self
+            .inner
+            .update(cnd(high, low, close, 0.0)?)
+            .map(|o| StochValue { k: o.k, d: o.d }))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -331,6 +343,10 @@ impl ObvNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, close: f64, volume: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(close, close, close, volume)?))
+    }
+    #[napi]
     pub fn batch(&mut self, close: Vec<f64>, volume: Vec<f64>) -> napi::Result<Vec<f64>> {
         if close.len() != volume.len() {
             return Err(NapiError::from_reason(
@@ -376,6 +392,21 @@ impl AdxNode {
         }
     }
     #[napi]
+    pub fn update(
+        &mut self,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<AdxValue>> {
+        Ok(self.inner.update(cnd(high, low, close, 0.0)?).map(|o| {
+            AdxValue {
+                plus_di: o.plus_di,
+                minus_di: o.minus_di,
+                adx: o.adx,
+            }
+        }))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -412,6 +443,10 @@ impl CciNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64, close: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, close, 0.0)?))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -443,6 +478,10 @@ impl WilliamsRNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64, close: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, close, 0.0)?))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -474,6 +513,16 @@ impl MfiNode {
         }
     }
     #[napi]
+    pub fn update(
+        &mut self,
+        high: f64,
+        low: f64,
+        close: f64,
+        volume: f64,
+    ) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, close, volume)?))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -506,6 +555,10 @@ impl PsarNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64, close: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, close, 0.0)?))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -548,6 +601,21 @@ impl KeltnerNode {
         }
     }
     #[napi]
+    pub fn update(
+        &mut self,
+        high: f64,
+        low: f64,
+        close: f64,
+    ) -> napi::Result<Option<KeltnerValue>> {
+        Ok(self.inner.update(cnd(high, low, close, 0.0)?).map(|o| {
+            KeltnerValue {
+                upper: o.upper,
+                middle: o.middle,
+                lower: o.lower,
+            }
+        }))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -587,6 +655,16 @@ impl DonchianNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64) -> napi::Result<Option<DonchianValue>> {
+        Ok(self.inner.update(cnd(high, low, low, 0.0)?).map(|o| {
+            DonchianValue {
+                upper: o.upper,
+                middle: o.middle,
+                lower: o.lower,
+            }
+        }))
+    }
+    #[napi]
     pub fn batch(&mut self, high: Vec<f64>, low: Vec<f64>) -> napi::Result<Vec<f64>> {
         let n = high.len();
         let mut out = vec![f64::NAN; n * 3];
@@ -619,6 +697,16 @@ impl VwapNode {
         }
     }
     #[napi]
+    pub fn update(
+        &mut self,
+        high: f64,
+        low: f64,
+        close: f64,
+        volume: f64,
+    ) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, close, volume)?))
+    }
+    #[napi]
     pub fn batch(
         &mut self,
         high: Vec<f64>,
@@ -651,6 +739,10 @@ impl AoNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64) -> napi::Result<Option<f64>> {
+        Ok(self.inner.update(cnd(high, low, low, 0.0)?))
+    }
+    #[napi]
     pub fn batch(&mut self, high: Vec<f64>, low: Vec<f64>) -> napi::Result<Vec<f64>> {
         let mut out = Vec::with_capacity(high.len());
         for i in 0..high.len() {
@@ -683,6 +775,13 @@ impl AroonNode {
         }
     }
     #[napi]
+    pub fn update(&mut self, high: f64, low: f64) -> napi::Result<Option<AroonValue>> {
+        Ok(self
+            .inner
+            .update(cnd(high, low, low, 0.0)?)
+            .map(|o| AroonValue { up: o.up, down: o.down }))
+    }
+    #[napi]
     pub fn batch(&mut self, high: Vec<f64>, low: Vec<f64>) -> napi::Result<Vec<f64>> {
         let n = high.len();
         let mut out = vec![f64::NAN; n * 2];