fixed issue on udpstreamer trigger logic

Common/Client/go/wshub/capture_shortwindow_test.go

@@ -0,0 +1,75 @@
+package wshub
+
+import (
+	"math"
+	"testing"
+)
+
+// A short window at a high sample rate fits in a ring's initial capacity, so the
+// retune sweep used to leave it there — and a ring holding exactly the window has
+// already rolled past the front of a capture by the time that capture is read,
+// which happens a post-window plus captureMarginSec after the trigger fires.
+//
+// 1 MSps over a 200 ms window: 200 k points fit in the 250 k initial ring, and
+// every shot came back missing its first 123 ms.
+func TestCaptureWholeAtHighRateShortWindow(t *testing.T) {
+	const (
+		key      = "s1:Ch1"
+		rate     = 1e6
+		window   = 0.2
+		prePct   = 20.0
+		batchSec = 1.0 / 30.0
+		simSec   = 6.0
+	)
+
+	h := NewHub()
+	h.SetRingBudget(defaultRingPts)
+	h.rings[key] = newSigRing(ringCapInitial)
+	h.trigger.SetConfig(trigConfig{signalKey: key, edge: "rising", threshold: 0,
+		windowSec: window, prePercent: prePct, mode: "normal", holdoffSec: 0.2})
+
+	rateHz := float64(rate)
+	nBatch := int(rateHz * batchSec)
+	ts := make([]float64, nBatch)
+	vs := make([]float64, nBatch)
+
+	armed, shots := false, 0
+	for now := 0.0; now < simSec; now += batchSec {
+		for i := range ts {
+			ts[i] = now + float64(i)/rateHz
+			vs[i] = math.Sin(2 * math.Pi * 5 * ts[i]) // a rising crossing every 200 ms
+		}
+		h.ingest(key, 1, ts, vs)
+		h.retuneRings(now)
+		h.refreshTriggerFill()
+
+		if !armed && now > 2 {
+			h.trigger.Arm()
+			armed = true
+		}
+		trigTime, pre, post, ok := h.trigger.dueCapture(now + batchSec)
+		if !ok {
+			if h.trigger.dueRearm(now + batchSec) {
+				h.trigger.Arm()
+			}
+			continue
+		}
+		t0 := trigTime - pre
+		buf := h.buildTriggerCapture(trigTime, pre, post)
+		if buf == nil {
+			t.Fatalf("shot at t=%.4f produced no frame at all", trigTime)
+		}
+		first, last, n := decodeCaptureSpan(t, buf, key)
+		shots++
+		if lost := first - t0; lost > shortCaptureTol*window {
+			_, span := h.rings[key].stats()
+			t.Errorf("shot at t=%.4f is missing %.0f ms at the front of its %.0f ms window "+
+				"(got [%.4f,%.4f], %d pts; ring holds %.4f s in %d points)",
+				trigTime, 1e3*lost, 1e3*window, first, last, n, span, h.rings[key].capacity())
+		}
+		h.trigger.markTriggered(now + batchSec)
+	}
+	if shots < 3 {
+		t.Fatalf("only %d shots in %.0f s", shots, simSec)
+	}
+}