add failing test for JWKS key with unknown curve

ecdsa_test.go

@@ -0,0 +1,30 @@
+package keyfunc
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/golang-jwt/jwt/v4"
+)
+
+func TestBadCurve(t *testing.T) {
+	const (
+		badJWKS = `{"keys":[{"kty":"EC","crv":"BAD","x":"MKBCTNIcKUSDii11ySs3526iDZ8AiTo7Tu6KPAqv7D4","y":"4Etl6SRW2YiLUrN5vfvVHuhp7x8PxltmWWlbbM4IFyM","use":"sig","kid":"1"}]}`
+		someJWT = `eyJhbGciOiJFUzI1NiIsImtpZCI6IjEiLCJ0eXAiOiJKV1QifQ.e30.Q1EeyWUv6XEA0gMLwTFoNhx7Hq1MbVwjI2k9FZPSa-myKW1wYn1X6rHtRyuV-2MEzvimCskFD-afL7UzvdWBQg`
+	)
+
+	jwks, err := NewJSON(json.RawMessage(badJWKS))
+	if err != nil {
+		t.Fatalf("Failed to create JWKS from JSON: %v", err)
+	}
+
+	defer func() {
+		if r := recover(); r != nil {
+			t.Fatalf("panic")
+		}
+	}()
+
+	if _, err = jwt.Parse(someJWT, jwks.Keyfunc); err == nil {
+		t.Fatal("No error for bad curve")
+	}
+}