From 01d9ff07cf5ccb2fcd5d940070dc31b93557d5be Mon Sep 17 00:00:00 2001
From: m5l14i11 <siarhei.melnik@proton.me>
Date: Tue, 1 Aug 2023 13:22:48 +0300
Subject: [PATCH] shrinking

---
 ta_lib/patterns/src/lib.rs       |  1 +
 ta_lib/patterns/src/shrinking.rs | 68 ++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 ta_lib/patterns/src/shrinking.rs

diff --git a/ta_lib/patterns/src/lib.rs b/ta_lib/patterns/src/lib.rs
index 9ce8192e..e82b9114 100644
--- a/ta_lib/patterns/src/lib.rs
+++ b/ta_lib/patterns/src/lib.rs
@@ -6,4 +6,5 @@ pub mod counterattack;
 pub mod doji;
 pub mod double_doji;
 pub mod marubozu;
+pub mod shrinking;
 pub mod tasuki;
diff --git a/ta_lib/patterns/src/shrinking.rs b/ta_lib/patterns/src/shrinking.rs
new file mode 100644
index 00000000..2046c9f0
--- /dev/null
+++ b/ta_lib/patterns/src/shrinking.rs
@@ -0,0 +1,68 @@
+use core::series::Series;
+
+pub fn bullish(open: &[f64], high: &[f64], low: &[f64], close: &[f64]) -> Vec<bool> {
+    let open = Series::from(open);
+    let high = Series::from(high);
+    let low = Series::from(low);
+    let close = Series::from(close);
+
+    (close.gt(&open)
+        & close.gt(&high.shift(1))
+        & close.gt(&high.shift(2))
+        & close.gt(&high.shift(3))
+        & high.shift(1).lt(&high.shift(2))
+        & high.shift(2).lt(&high.shift(3))
+        & low.shift(1).eq(&low.shift(2))
+        & low.shift(2).eq(&low.shift(3))
+        & close.shift(4).lt(&open.shift(4)))
+    .into()
+}
+
+pub fn bearish(open: &[f64], high: &[f64], low: &[f64], close: &[f64]) -> Vec<bool> {
+    let open = Series::from(open);
+    let high = Series::from(high);
+    let low = Series::from(low);
+    let close = Series::from(close);
+
+    (close.lt(&open)
+        & close.lt(&low.shift(1))
+        & close.lt(&low.shift(2))
+        & close.lt(&low.shift(3))
+        & low.shift(1).lt(&low.shift(2))
+        & low.shift(2).lt(&low.shift(3))
+        & high.shift(1).eq(&high.shift(2))
+        & high.shift(2).eq(&high.shift(3))
+        & close.shift(4).gt(&open.shift(4)))
+    .into()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_shrinking_bullish() {
+        let open = vec![4.0, 3.0, 4.0, 3.0, 4.0];
+        let high = vec![4.5, 3.5, 4.5, 3.5, 4.5];
+        let low = vec![4.0, 3.0, 4.0, 3.0, 4.0];
+        let close = vec![4.5, 3.5, 4.5, 3.5, 4.5];
+        let expected = vec![false, false, false, false, false];
+
+        let result = bullish(&open, &high, &low, &close);
+
+        assert_eq!(result, expected);
+    }
+
+    #[test]
+    fn test_shrinking_bearish() {
+        let open = vec![4.0, 3.0, 4.0, 3.0, 4.0];
+        let high = vec![4.0, 3.0, 4.0, 3.0, 4.0];
+        let low = vec![3.5, 2.5, 3.5, 2.5, 3.5];
+        let close = vec![3.5, 2.5, 3.5, 2.5, 3.5];
+        let expected = vec![false, false, false, false, false];
+
+        let result = bearish(&open, &high, &low, &close);
+
+        assert_eq!(result, expected);
+    }
+}