fix(drivers): bundle growatt 2.1.3, a PV-only Growatt shows no battery

.changeset/bundle-growatt-213.md

@@ -0,0 +1,7 @@
+---
+"ftw": patch
+---
+
+Bundle growatt 2.1.3. A Growatt inverter with no battery no longer shows a
+second battery at 0 W and 0 % beside the site's real one: the driver now
+reports a battery only when its voltage, charge level or power is above 0.

drivers/BUNDLED_SOURCE.json

@@ -16,7 +16,7 @@
     "from the signed channel. Run scripts/sync-bundled-drivers.sh to update."
   ],
   "repository": "srcfl/device-drivers",
-  "commit": "e463c653763d5e5c7d28af97bd381eed4fafa47c",
+  "commit": "e07d27038e83e431cc01c1cd988ffcb1997355c0",
   "source_dir": "drivers/lua",
   "drivers": [
     "ambibox_v2x", "ctek", "ctek_hybrid", "ctek_v2", "deye", "easee_cloud",

go/internal/drivers/growatt_test.go

@@ -0,0 +1,47 @@
+package drivers
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+
+	"github.com/srcfl/ftw/go/internal/telemetry"
+)
+
+// A PV-only Growatt answers its battery registers with 0. It used to emit a
+// battery anyway, and Overview drew a second battery at 0 W and 0 % beside
+// the site's real one (srcfl/ftw#1669). A hybrid still reports its battery.
+func TestGrowattEmitsABatteryOnlyWhenOneAnswers(t *testing.T) {
+	for _, tc := range []struct {
+		name    string
+		regs    map[uint16]uint16
+		battery bool
+	}{
+		{"PV only", map[uint16]uint16{2: 25000}, false},
+		{"hybrid", map[uint16]uint16{2: 25000, 1010: 100, 1013: 480, 1014: 50}, true},
+		{"hybrid at 0 %", map[uint16]uint16{2: 25000, 1013: 520}, true},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			tel := telemetry.NewStore()
+			env := NewHostEnv("growatt", tel).WithModbus(&pixiiTestModbus{regs: tc.regs})
+			d, err := NewLuaDriver(filepath.Join("..", "..", "..", "drivers", "growatt.lua"), env)
+			if err != nil {
+				t.Fatalf("load Growatt driver: %v", err)
+			}
+			t.Cleanup(d.Cleanup)
+			if err := d.Init(context.Background(), nil); err != nil {
+				t.Fatalf("init: %v", err)
+			}
+			if _, err := d.Poll(context.Background()); err != nil {
+				t.Fatalf("poll: %v", err)
+			}
+			if pv := tel.Get("growatt", telemetry.DerPV); pv == nil || pv.RawW != -2500 {
+				t.Fatalf("PV reading %+v, want -2500 W", pv)
+			}
+			bat := tel.Get("growatt", telemetry.DerBattery)
+			if (bat != nil) != tc.battery {
+				t.Fatalf("battery reading %+v, want present=%v", bat, tc.battery)
+			}
+		})
+	}
+}