up

internal/dxcc/dxcc_test.go

@@ -17,6 +17,22 @@ United States:            05:  08:  NA:   37.53:    91.67:     5.0:  K:
     =W1AW(5)[7],K,N,W,AA,AB,AC,AD,AE,AF,AG,AH,AI,AJ,AK;
 `
 
+// cty.dat stores longitude "+ for West"; we normalise to the standard
+// "+ for East" so bearing/distance math (and the cluster map) aren't mirrored.
+// Regression guard for the Svalbard-azimuth bug (356° instead of 4°).
+func TestLongitudeSign(t *testing.T) {
+	db, err := Load(strings.NewReader(sampleCty))
+	if err != nil {
+		t.Fatalf("load: %v", err)
+	}
+	if m, ok := db.Lookup("F4BPO"); !ok || m.Lon <= 0 { // France 2°E → +2
+		t.Errorf("France lon = %v, want positive (East)", m.Lon)
+	}
+	if m, ok := db.Lookup("K1ABC"); !ok || m.Lon >= 0 { // USA 92°W → ~-91.67
+		t.Errorf("USA lon = %v, want negative (West)", m.Lon)
+	}
+}
+
 func TestLookup(t *testing.T) {
 	db, err := Load(strings.NewReader(sampleCty))
 	if err != nil {