Initial commit: 可转债轮动分析系统

- 实时行情：东财push2主源 + 腾讯批量报价备用源（自动切换）
- 历史K线：东财push2his主源 + 腾讯web子域备用源（含熔断机制）
- 增量同步：支持 -incr/-since 参数按存档日期增量入库
- 策略回测：净值曲线/10指标/基准对比，含基本面过滤
- 用户认证：用户名密码 + 邮箱验证码双登录方式
- 前端：三Tab SPA（实时行情/策略回测/数据管理）

internal/strategy/lowprice_test.go

@@ -0,0 +1,139 @@
+package strategy
+
+import (
+	"context"
+	"testing"
+
+	"stock-analysis/internal/backtest"
+)
+
+func TestLowPrice_Name(t *testing.T) {
+	s := NewLowPrice(LowPriceParams{TopN: 10, Rebalance: 21, MinPrice: 80, MaxPrice: 130})
+	name := s.Name()
+	if name == "" {
+		t.Error("strategy name should not be empty")
+	}
+}
+
+func TestLowPrice_FirstDaySelectsTopN(t *testing.T) {
+	s := NewLowPrice(LowPriceParams{TopN: 3, Rebalance: 5, MinPrice: 80, MaxPrice: 130})
+
+	universe := []backtest.Quote{
+		{Code: "A", Price: 100},
+		{Code: "B", Price: 90},
+		{Code: "C", Price: 110},
+		{Code: "D", Price: 85},
+		{Code: "E", Price: 120},
+		{Code: "F", Price: 75}, // 低于 MinPrice，应被过滤
+		{Code: "G", Price: 135}, // 高于 MaxPrice，应被过滤
+	}
+
+	targets, err := s.OnBar(context.Background(), "2020-01-02", universe, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(targets) != 3 {
+		t.Fatalf("expected 3 targets, got %d", len(targets))
+	}
+
+	// 按价格升序，应选 D(85), B(90), A(100)
+	codes := make(map[string]bool)
+	for _, tg := range targets {
+		codes[tg.Code] = true
+	}
+	if !codes["D"] || !codes["B"] || !codes["A"] {
+		t.Errorf("expected codes D, B, A, got %v", codes)
+	}
+
+	// 权重应为等权 1/3
+	for _, tg := range targets {
+		if tg.Weight != 1.0/3.0 {
+			t.Errorf("weight for %s: expected %f, got %f", tg.Code, 1.0/3.0, tg.Weight)
+		}
+	}
+}
+
+func TestLowPrice_NonRebalanceDay(t *testing.T) {
+	s := NewLowPrice(LowPriceParams{TopN: 3, Rebalance: 5, MinPrice: 80, MaxPrice: 130})
+
+	universe := []backtest.Quote{
+		{Code: "A", Price: 100},
+	}
+
+	// 第 1 天：调仓
+	targets, _ := s.OnBar(context.Background(), "2020-01-02", universe, nil)
+	if targets == nil {
+		t.Error("day 1 should rebalance")
+	}
+
+	// 第 2-5 天：不调仓
+	for i := 0; i < 4; i++ {
+		targets, _ = s.OnBar(context.Background(), "2020-01-02", universe, nil)
+		if targets != nil {
+			t.Errorf("day %d should not rebalance", i+2)
+		}
+	}
+
+	// 第 6 天：调仓
+	targets, _ = s.OnBar(context.Background(), "2020-01-02", universe, nil)
+	if targets == nil {
+		t.Error("day 6 should rebalance")
+	}
+}
+
+func TestLowPrice_NoQualifiedCandidates(t *testing.T) {
+	s := NewLowPrice(LowPriceParams{TopN: 3, Rebalance: 5, MinPrice: 80, MaxPrice: 130})
+
+	// 所有标的价格都不在范围内
+	universe := []backtest.Quote{
+		{Code: "A", Price: 50},
+		{Code: "B", Price: 200},
+	}
+
+	targets, err := s.OnBar(context.Background(), "2020-01-02", universe, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if targets != nil {
+		t.Error("expected nil targets when no qualified candidates")
+	}
+}
+
+func TestLowPrice_FewerThanTopN(t *testing.T) {
+	s := NewLowPrice(LowPriceParams{TopN: 10, Rebalance: 5, MinPrice: 80, MaxPrice: 130})
+
+	universe := []backtest.Quote{
+		{Code: "A", Price: 100},
+		{Code: "B", Price: 110},
+	}
+
+	targets, err := s.OnBar(context.Background(), "2020-01-02", universe, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(targets) != 2 {
+		t.Fatalf("expected 2 targets, got %d", len(targets))
+	}
+	// 权重应为等权 1/2
+	for _, tg := range targets {
+		if tg.Weight != 0.5 {
+			t.Errorf("weight for %s: expected 0.5, got %f", tg.Code, tg.Weight)
+		}
+	}
+}
+
+func TestDefaultLowPriceParams(t *testing.T) {
+	p := DefaultLowPriceParams()
+	if p.TopN != 10 {
+		t.Errorf("TopN: expected 10, got %d", p.TopN)
+	}
+	if p.Rebalance != 21 {
+		t.Errorf("Rebalance: expected 21, got %d", p.Rebalance)
+	}
+	if p.MinPrice != 80 {
+		t.Errorf("MinPrice: expected 80, got %f", p.MinPrice)
+	}
+	if p.MaxPrice != 130 {
+		t.Errorf("MaxPrice: expected 130, got %f", p.MaxPrice)
+	}
+}