Split intraday fills across execution quotes

crates/fidc-core/tests/explicit_order_flow.rs

@@ -638,6 +638,150 @@ fn broker_emits_partial_fill_reason_when_intraday_quote_liquidity_exhausted() {
     );
 }
 
+#[test]
+fn broker_splits_intraday_quote_fills_and_tracks_commission_by_order() {
+    let date = NaiveDate::from_ymd_opt(2024, 1, 10).unwrap();
+    let data = DataSet::from_components_with_actions_and_quotes(
+        vec![Instrument {
+            symbol: "000002.SZ".to_string(),
+            name: "Test".to_string(),
+            board: "SZ".to_string(),
+            round_lot: 100,
+            listed_at: None,
+            delisted_at: None,
+            status: "active".to_string(),
+        }],
+        vec![DailyMarketSnapshot {
+            date,
+            symbol: "000002.SZ".to_string(),
+            timestamp: Some("2024-01-10 10:18:00".to_string()),
+            day_open: 10.0,
+            open: 10.0,
+            high: 10.2,
+            low: 9.8,
+            close: 10.0,
+            last_price: 10.0,
+            bid1: 9.99,
+            ask1: 10.01,
+            prev_close: 10.0,
+            volume: 100_000,
+            tick_volume: 100_000,
+            bid1_volume: 80_000,
+            ask1_volume: 80_000,
+            trading_phase: Some("continuous".to_string()),
+            paused: false,
+            upper_limit: 11.0,
+            lower_limit: 9.0,
+            price_tick: 0.01,
+        }],
+        vec![DailyFactorSnapshot {
+            date,
+            symbol: "000002.SZ".to_string(),
+            market_cap_bn: 50.0,
+            free_float_cap_bn: 45.0,
+            pe_ttm: 15.0,
+            turnover_ratio: Some(2.0),
+            effective_turnover_ratio: Some(1.8),
+            extra_factors: BTreeMap::new(),
+        }],
+        vec![CandidateEligibility {
+            date,
+            symbol: "000002.SZ".to_string(),
+            is_st: false,
+            is_new_listing: false,
+            is_paused: false,
+            allow_buy: true,
+            allow_sell: true,
+            is_kcb: false,
+            is_one_yuan: false,
+        }],
+        vec![BenchmarkSnapshot {
+            date,
+            benchmark: "000300.SH".to_string(),
+            open: 100.0,
+            close: 100.0,
+            prev_close: 99.0,
+            volume: 1_000_000,
+        }],
+        Vec::new(),
+        vec![
+            IntradayExecutionQuote {
+                date,
+                symbol: "000002.SZ".to_string(),
+                timestamp: date.and_hms_opt(10, 18, 3).unwrap(),
+                last_price: 10.01,
+                bid1: 10.0,
+                ask1: 10.02,
+                bid1_volume: 1,
+                ask1_volume: 1,
+                volume_delta: 1,
+                amount_delta: 0.0,
+                trading_phase: Some("continuous".to_string()),
+            },
+            IntradayExecutionQuote {
+                date,
+                symbol: "000002.SZ".to_string(),
+                timestamp: date.and_hms_opt(10, 18, 6).unwrap(),
+                last_price: 10.03,
+                bid1: 10.02,
+                ask1: 10.04,
+                bid1_volume: 1,
+                ask1_volume: 1,
+                volume_delta: 1,
+                amount_delta: 0.0,
+                trading_phase: Some("continuous".to_string()),
+            },
+        ],
+    )
+    .expect("dataset");
+    let mut portfolio = PortfolioState::new(1_000_000.0);
+    let broker = BrokerSimulator::new_with_execution_price(
+        ChinaAShareCostModel::default(),
+        ChinaEquityRuleHooks::default(),
+        PriceField::Last,
+    );
+
+    let report = broker
+        .execute(
+            date,
+            &mut portfolio,
+            &data,
+            &StrategyDecision {
+                rebalance: false,
+                target_weights: BTreeMap::new(),
+                exit_symbols: BTreeSet::new(),
+                order_intents: vec![OrderIntent::Value {
+                    symbol: "000002.SZ".to_string(),
+                    value: 2_500.0,
+                    reason: "intraday_split_fill".to_string(),
+                }],
+                notes: Vec::new(),
+                diagnostics: Vec::new(),
+            },
+        )
+        .expect("broker execution");
+
+    assert_eq!(report.order_events.len(), 1);
+    assert_eq!(
+        report.order_events[0].status,
+        fidc_core::OrderStatus::Filled
+    );
+    assert_eq!(report.fill_events.len(), 2);
+    assert_eq!(report.fill_events[0].quantity, 100);
+    assert_eq!(report.fill_events[1].quantity, 100);
+    assert!((report.fill_events[0].price - 10.02).abs() < 1e-9);
+    assert!((report.fill_events[1].price - 10.04).abs() < 1e-9);
+    assert!((report.fill_events[0].commission - 5.0).abs() < 1e-9);
+    assert_eq!(report.fill_events[1].commission, 0.0);
+    assert_eq!(report.account_events.len(), 2);
+    assert!(
+        report
+            .diagnostics
+            .iter()
+            .any(|item| item.contains("order_split_fill symbol=000002.SZ side=buy"))
+    );
+}
+
 #[test]
 fn rebalance_optimizer_skips_unfunded_buy_when_existing_position_cannot_sell() {
     let prev_date = NaiveDate::from_ymd_opt(2024, 1, 9).unwrap();