perf: avoid board normalization allocations

crates/fidc-core/src/instrument.rs

@@ -21,17 +21,29 @@ impl Instrument {
     }
 
     pub fn minimum_order_quantity(&self) -> u32 {
-        match self.board.trim().to_ascii_uppercase().as_str() {
-            "KSH" => 200,
-            "BJS" | "BJ" | "BJSE" => 100,
-            _ => self.effective_round_lot(),
+        let board = self.board.trim();
+        if board.eq_ignore_ascii_case("KSH") {
+            200
+        } else if board.eq_ignore_ascii_case("BJS")
+            || board.eq_ignore_ascii_case("BJ")
+            || board.eq_ignore_ascii_case("BJSE")
+        {
+            100
+        } else {
+            self.effective_round_lot()
         }
     }
 
     pub fn order_step_size(&self) -> u32 {
-        match self.board.trim().to_ascii_uppercase().as_str() {
-            "KSH" | "BJS" | "BJ" | "BJSE" => 1,
-            _ => self.effective_round_lot(),
+        let board = self.board.trim();
+        if board.eq_ignore_ascii_case("KSH")
+            || board.eq_ignore_ascii_case("BJS")
+            || board.eq_ignore_ascii_case("BJ")
+            || board.eq_ignore_ascii_case("BJSE")
+        {
+            1
+        } else {
+            self.effective_round_lot()
         }
     }
 
@@ -56,6 +68,38 @@ fn default_status() -> String {
     "active".to_string()
 }
 
+#[cfg(test)]
+mod tests {
+    use super::Instrument;
+
+    fn instrument(board: &str, round_lot: u32) -> Instrument {
+        Instrument {
+            symbol: "000001.SZ".to_string(),
+            name: "test".to_string(),
+            board: board.to_string(),
+            round_lot,
+            listed_at: None,
+            delisted_at: None,
+            status: "active".to_string(),
+        }
+    }
+
+    #[test]
+    fn order_quantity_rules_are_case_insensitive_without_allocating_normalized_boards() {
+        let kcb = instrument(" kSh ", 100);
+        assert_eq!(kcb.minimum_order_quantity(), 200);
+        assert_eq!(kcb.order_step_size(), 1);
+
+        let bjse = instrument("bjse", 100);
+        assert_eq!(bjse.minimum_order_quantity(), 100);
+        assert_eq!(bjse.order_step_size(), 1);
+
+        let main_board = instrument("SZSE", 50);
+        assert_eq!(main_board.minimum_order_quantity(), 50);
+        assert_eq!(main_board.order_step_size(), 50);
+    }
+}
+
 mod optional_date_format {
     use chrono::NaiveDate;
     use serde::{self, Deserialize, Deserializer, Serializer};