fix(battery): render a detected battery at 0% instead of disabling the segment

Enabled() treated err == nil && Percentage == 0 as a "no battery"
sentinel, but every platform backend already signals "no battery"
through a dedicated error (NoBatteryError/ErrNotFound) before that
point is reached. A present battery genuinely reporting 0% charge
was therefore hidden instead of rendered.

Also guard against a nil Info dereference on the display_error path,
where BatteryState() returns (nil, err) for any non-NoBatteryError.

Fixes #7782

Author: claude

src/segments/battery.go

@@ -35,11 +35,8 @@ func (b *Battery) Enabled() bool {
 		return false
 	}
 
-	b.Info = *info
-
-	// case on computer without batteries(no error, empty array)
-	if err == nil && b.Percentage == 0 {
-		return false
+	if info != nil {
+		b.Info = *info
 	}
 
 	switch b.State {

src/segments/battery_test.go

@@ -0,0 +1,83 @@
+package segments
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/jandedobbeleer/oh-my-posh/src/runtime/battery"
+	"github.com/jandedobbeleer/oh-my-posh/src/runtime/mock"
+	"github.com/jandedobbeleer/oh-my-posh/src/segments/options"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestBatteryEnabled(t *testing.T) {
+	cases := []struct {
+		Case            string
+		Info            *battery.Info
+		Error           error
+		DisplayError    bool
+		ExpectedEnabled bool
+		Expected        string
+	}{
+		{
+			Case:            "detected battery at 0%",
+			Info:            &battery.Info{Percentage: 0, State: battery.NotCharging},
+			ExpectedEnabled: true,
+			Expected:        "0",
+		},
+		{
+			Case:            "discharging",
+			Info:            &battery.Info{Percentage: 42, State: battery.Discharging},
+			ExpectedEnabled: true,
+			Expected:        "42",
+		},
+		{
+			Case:            "full",
+			Info:            &battery.Info{Percentage: 100, State: battery.Full},
+			ExpectedEnabled: true,
+			Expected:        "100",
+		},
+		{
+			Case:            "no battery present",
+			Info:            nil,
+			Error:           &battery.NoBatteryError{},
+			ExpectedEnabled: false,
+		},
+		{
+			Case:            "retrieval error, display_error disabled",
+			Info:            nil,
+			Error:           errors.New("boom"),
+			ExpectedEnabled: false,
+		},
+		{
+			Case:            "retrieval error, display_error enabled",
+			Info:            nil,
+			Error:           errors.New("boom"),
+			DisplayError:    true,
+			ExpectedEnabled: true,
+			Expected:        "boom",
+		},
+	}
+
+	for _, tc := range cases {
+		env := new(mock.Environment)
+		env.On("IsWsl").Return(false)
+		env.On("BatteryState").Return(tc.Info, tc.Error)
+
+		props := options.Map{}
+		if tc.DisplayError {
+			props[options.DisplayError] = true
+		}
+
+		b := &Battery{}
+		b.Init(props, env)
+
+		got := b.Enabled()
+
+		assert.Equal(t, tc.ExpectedEnabled, got, tc.Case)
+		if tc.ExpectedEnabled {
+			assert.Equal(t, tc.Expected, renderTemplate(env, b.Template(), b), tc.Case)
+		}
+	}
+}