Add evaluation of arrays to interpreter

2 files changed, 50 insertions, 6 deletions

diff --git a/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java b/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
index 6112c8e..5f42065 100644
--- a/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
@@ -1,25 +1,31 @@
 package org.zwobble.couscous.tests.interpreter;
 
 import com.google.common.collect.ImmutableMap;
+import org.hamcrest.Matcher;
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
-import org.zwobble.couscous.types.ScalarType;
 import org.zwobble.couscous.interpreter.Environment;
 import org.zwobble.couscous.interpreter.JavaProject;
 import org.zwobble.couscous.interpreter.MapBackedProject;
 import org.zwobble.couscous.interpreter.StackFrameBuilder;
 import org.zwobble.couscous.interpreter.errors.*;
+import org.zwobble.couscous.interpreter.values.ArrayInterpreterValue;
 import org.zwobble.couscous.interpreter.values.IntegerInterpreterValue;
 import org.zwobble.couscous.interpreter.values.InterpreterValue;
 import org.zwobble.couscous.interpreter.values.StringInterpreterValue;
 import org.zwobble.couscous.tests.BackendEvalTests;
+import org.zwobble.couscous.types.ScalarType;
 import org.zwobble.couscous.types.Types;
 import org.zwobble.couscous.values.PrimitiveValue;
 
 import java.util.List;
 import java.util.Optional;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.equalTo;
 import static org.junit.Assert.assertEquals;
+import static org.zwobble.couscous.ast.ArrayNode.array;
 import static org.zwobble.couscous.ast.AssignmentNode.assign;
 import static org.zwobble.couscous.ast.AssignmentNode.assignStatement;
 import static org.zwobble.couscous.ast.CastNode.cast;
@@ -34,6 +40,7 @@ import static org.zwobble.couscous.interpreter.Evaluator.eval;
 import static org.zwobble.couscous.interpreter.values.InterpreterValues.value;
 import static org.zwobble.couscous.tests.TestIds.ANY_ID;
 import static org.zwobble.couscous.tests.util.ExtraAsserts.assertThrows;
+import static org.zwobble.couscous.tests.util.ExtraMatchers.*;
 import static org.zwobble.couscous.util.ExtraLists.list;
 
 public class EvaluatorTests extends BackendEvalTests {
@@ -225,7 +232,31 @@ public class EvaluatorTests extends BackendEvalTests {
         assertEquals(Types.STRING, exception.getExpected());
         assertEquals(Types.INT, exception.getActual());
     }
-    
+
+    @Test
+    public void canEvaluateEmptyArray() {
+        InterpreterValue array = eval(emptyEnvironment(), array(Types.STRING, list()));
+        assertThat(array, isArrayInterpreterValue(Types.STRING, list()));
+    }
+
+    @Test
+    public void canEvaluateArrayWithElements() {
+        InterpreterValue array = eval(emptyEnvironment(), array(Types.STRING, list(literal("one"), literal("two"))));
+        assertThat(
+            array,
+            isArrayInterpreterValue(Types.STRING, list(
+                StringInterpreterValue.of("one"),
+                StringInterpreterValue.of("two"))));
+    }
+
+    private Matcher<InterpreterValue> isArrayInterpreterValue(ScalarType elementType, List<InterpreterValue> elements) {
+        return isInstance(
+            ArrayInterpreterValue.class,
+            allOf(
+                hasFeature("elementType", value -> value.getElementType(), equalTo(elementType)),
+                hasFeature("elements", value -> value.getElements(), containsExactElements(elements))));
+    }
+
     private static Environment emptyEnvironment() {
         return new Environment(
             JavaProject.builder().build(),
diff --git a/src/test/java/org/zwobble/couscous/tests/util/ExtraMatchers.java b/src/test/java/org/zwobble/couscous/tests/util/ExtraMatchers.java
index d79cb05..074e449 100644
--- a/src/test/java/org/zwobble/couscous/tests/util/ExtraMatchers.java
+++ b/src/test/java/org/zwobble/couscous/tests/util/ExtraMatchers.java
@@ -1,12 +1,13 @@
 package org.zwobble.couscous.tests.util;
 
-import org.hamcrest.Description;
-import org.hamcrest.DiagnosingMatcher;
-import org.hamcrest.FeatureMatcher;
-import org.hamcrest.Matcher;
+import org.hamcrest.*;
 
+import java.util.List;
 import java.util.function.Function;
 
+import static org.hamcrest.Matchers.equalTo;
+import static org.zwobble.couscous.util.ExtraLists.eagerMap;
+
 public class ExtraMatchers {
     public static <T, U> Matcher<T> isInstance(Class<U> type, Matcher<? super U> downcastMatcher) {
         return new DiagnosingMatcher<T>() {
@@ -51,4 +52,16 @@ public class ExtraMatchers {
             }
         };
     }
+
+    public static <T> Matcher<Iterable<? extends T>> containsExactly(List<Matcher<? super T>> matchers) {
+        if (matchers.isEmpty()) {
+            return Matchers.emptyIterable();
+        } else {
+            return Matchers.contains(matchers);
+        }
+    }
+
+    public static <T> Matcher<Iterable<? extends T>> containsExactElements(List<T> values) {
+        return containsExactly(eagerMap(values, value -> equalTo(value)));
+    }
 }