Add unit tests for array wildcards.

(Might be more suitable as `FixPathTest`s.)

Author: blackwinter

metafix/src/test/java/org/metafacture/metafix/HashValueTest.java

@@ -21,9 +21,11 @@
 import nl.jqno.equalsverifier.EqualsVerifier;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 
 import java.util.Arrays;
 
+@ExtendWith(MetafixToDo.Extension.class)
 public class HashValueTest {
 
     private static final String FIELD = "field";
@@ -383,6 +385,42 @@ public void shouldIterateOverFieldValuePairs() {
         );
     }
 
+    private void shouldFindArray(final String field) {
+        final Value.Hash hash = newHash();
+        hash.put(FIELD, Value.newArray(a -> a.add(VALUE)));
+
+        Assertions.assertEquals(VALUE, new FixPath(String.join(".", FIELD, field)).findIn(hash));
+    }
+
+    @Test
+    public void shouldFindArrayIndex() {
+        shouldFindArray("1");
+    }
+
+    @Test
+    @MetafixToDo("Expected String, got Array")
+    public void shouldFindArrayWildcard() {
+        shouldFindArray("$last");
+    }
+
+    private void shouldFindArraySubfield(final String field) {
+        final Value.Hash hash = newHash();
+        hash.put(FIELD, Value.newArray(a -> a.add(Value.newHash(h -> h.put(OTHER_FIELD, OTHER_VALUE)))));
+
+        Assertions.assertEquals(OTHER_VALUE, new FixPath(String.join(".", FIELD, field, OTHER_FIELD)).findIn(hash));
+    }
+
+    @Test
+    public void shouldFindArrayIndexSubfield() {
+        shouldFindArraySubfield("1");
+    }
+
+    @Test
+    @MetafixToDo("Expected String, got Array")
+    public void shouldFindArrayWildcardSubfield() {
+        shouldFindArraySubfield("$last");
+    }
+
     private Value.Hash newHash() {
         return Value.newHash().asHash();
     }