remove direct dependencies to apache beanutils and commons collections

scm-core/src/test/java/sonia/scm/util/ComparablesTest.java

@@ -0,0 +1,57 @@
+package sonia.scm.util;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Comparator;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class ComparablesTest {
+
+  @Test
+  void shouldCompare() {
+    One a = new One("a");
+    One b = new One("b");
+
+    Comparator<One> comparable = Comparables.comparator(One.class, "value");
+    assertThat(comparable.compare(a, b)).isEqualTo(-1);
+  }
+
+  @Test
+  void shouldThrowAnExceptionForNonExistingField() {
+    assertThrows(IllegalArgumentException.class, () -> Comparables.comparator(One.class, "awesome"));
+  }
+
+  @Test
+  void shouldThrowAnExceptionForNonComparableField() {
+    assertThrows(IllegalArgumentException.class, () -> Comparables.comparator(One.class, "nonComparable"));
+  }
+
+  @Test
+  void shouldThrowAnExceptionIfTheFieldHasNoGetter() {
+    assertThrows(IllegalArgumentException.class, () -> Comparables.comparator(One.class, "incredible"));
+  }
+
+  private static class One {
+
+    private String value;
+    private String incredible;
+    private NonComparable nonComparable;
+
+    One(String value) {
+      this.value = value;
+    }
+
+    public String getValue() {
+      return value;
+    }
+
+    public NonComparable getNonComparable() {
+      return nonComparable;
+    }
+  }
+
+  private static class NonComparable {}
+
+}