1 files changed, 25 insertions, 0 deletions
diff --git a/android-app/app/src/test/kotlin/org/terst/nav/ui/DirectionArrowViewTest.kt b/android-app/app/src/test/kotlin/org/terst/nav/ui/DirectionArrowViewTest.kt
new file mode 100644
index 0000000..e26b67d
--- /dev/null
+++ b/android-app/app/src/test/kotlin/org/terst/nav/ui/DirectionArrowViewTest.kt
@@ -0,0 +1,25 @@
+package org.terst.nav.ui
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class DirectionArrowViewTest {
+
+    @Test
+    fun `bearing is normalised — values over 360 wrap`() {
+        assertEquals(10f, normalizeBearing(370f), 0.001f)
+    }
+
+    @Test
+    fun `bearing is normalised — negative values wrap`() {
+        assertEquals(350f, normalizeBearing(-10f), 0.001f)
+    }
+
+    @Test
+    fun `bearing is normalised — exactly 360 becomes 0`() {
+        assertEquals(0f, normalizeBearing(360f), 0.001f)
+    }
+}
+
+// Top-level helper extracted from DirectionArrowView for testability
+fun normalizeBearing(deg: Float): Float = ((deg % 360f) + 360f) % 360f