Add evaluation of arrays to interpreter

6 files changed, 121 insertions, 20 deletions

diff --git a/src/main/java/org/zwobble/couscous/ast/ArrayNode.java b/src/main/java/org/zwobble/couscous/ast/ArrayNode.java
index ac4c284..78e6869 100644
--- a/src/main/java/org/zwobble/couscous/ast/ArrayNode.java
+++ b/src/main/java/org/zwobble/couscous/ast/ArrayNode.java
@@ -20,6 +20,10 @@ public class ArrayNode implements ExpressionNode {
         this.elements = elements;
     }
 
+    public Type getElementType() {
+        return elementType;
+    }
+
     public List<ExpressionNode> getElements() {
         return elements;
     }
diff --git a/src/main/java/org/zwobble/couscous/interpreter/Evaluator.java b/src/main/java/org/zwobble/couscous/interpreter/Evaluator.java
index 1082ed1..8c3d355 100644
--- a/src/main/java/org/zwobble/couscous/interpreter/Evaluator.java
+++ b/src/main/java/org/zwobble/couscous/interpreter/Evaluator.java
@@ -1,18 +1,19 @@
 package org.zwobble.couscous.interpreter;
 
 import org.zwobble.couscous.ast.*;
-import org.zwobble.couscous.types.ScalarType;
 import org.zwobble.couscous.ast.visitors.AssignableExpressionNodeVisitor;
 import org.zwobble.couscous.ast.visitors.ExpressionNodeMapper;
 import org.zwobble.couscous.interpreter.errors.ConditionMustBeBoolean;
 import org.zwobble.couscous.interpreter.errors.InvalidCast;
 import org.zwobble.couscous.interpreter.values.*;
+import org.zwobble.couscous.types.ScalarType;
 import org.zwobble.couscous.types.Types;
 
 import java.util.List;
 import java.util.stream.Collectors;
 
 import static org.zwobble.couscous.types.Types.erasure;
+import static org.zwobble.couscous.util.ExtraLists.eagerMap;
 
 public class Evaluator implements ExpressionNodeMapper<InterpreterValue> {
     public static InterpreterValue eval(Environment environment, ExpressionNode expression) {
@@ -52,8 +53,10 @@ public class Evaluator implements ExpressionNodeMapper<InterpreterValue> {
     }
 
     @Override
-    public InterpreterValue visit(ArrayNode arrayNode) {
-        throw new UnsupportedOperationException();
+    public InterpreterValue visit(ArrayNode array) {
+        return new ArrayInterpreterValue(
+            array.getElementType(),
+            eagerMap(array.getElements(), this::eval));
     }
 
     @Override
diff --git a/src/main/java/org/zwobble/couscous/interpreter/types/IntrinsicInterpreterType.java b/src/main/java/org/zwobble/couscous/interpreter/types/IntrinsicInterpreterType.java
index d69c855..190908b 100644
--- a/src/main/java/org/zwobble/couscous/interpreter/types/IntrinsicInterpreterType.java
+++ b/src/main/java/org/zwobble/couscous/interpreter/types/IntrinsicInterpreterType.java
@@ -22,7 +22,7 @@ import static org.zwobble.couscous.util.ExtraLists.list;
 import static org.zwobble.couscous.util.ExtraSets.set;
 
 public class IntrinsicInterpreterType implements InterpreterType {
-    public static <T> Builder<T> builder(Class<T> interpreterValueType, ScalarType reference) {
+    public static <T> Builder<T> builder(Class<T> interpreterValueType, Type reference) {
         return new Builder<>(interpreterValueType, reference);
     }
 
@@ -40,11 +40,11 @@ public class IntrinsicInterpreterType implements InterpreterType {
         private final ImmutableMap.Builder<MethodSignature, MethodValue> methods = ImmutableMap.builder();
         private final ImmutableMap.Builder<MethodSignature, StaticMethodValue> staticMethods = ImmutableMap.builder();
         private final Class<T> interpreterValueType;
-        private final ScalarType name;
+        private final Type type;
 
-        public Builder(Class<T> interpreterValueType, ScalarType name) {
+        public Builder(Class<T> interpreterValueType, Type type) {
             this.interpreterValueType = interpreterValueType;
-            this.name = name;
+            this.type = type;
         }
 
         public Builder<T> field(String name, ScalarType type) {
@@ -88,7 +88,7 @@ public class IntrinsicInterpreterType implements InterpreterType {
 
         public InterpreterType build() {
             return new IntrinsicInterpreterType(
-                name,
+                type,
                 fields.build(),
                 constructor,
                 methods.build(),
@@ -96,20 +96,20 @@ public class IntrinsicInterpreterType implements InterpreterType {
         }
     }
 
-    private final ScalarType name;
+    private final Type type;
     private final Map<String, FieldDeclarationNode> fields;
     private final MethodValue constructor;
     private final Map<MethodSignature, MethodValue> methods;
     private final Map<MethodSignature, StaticMethodValue> staticMethods;
 
     private IntrinsicInterpreterType(
-        ScalarType name,
+        Type type,
         Map<String, FieldDeclarationNode> fields,
         MethodValue constructor,
         Map<MethodSignature, MethodValue> methods,
         Map<MethodSignature, StaticMethodValue> staticMethods)
     {
-        this.name = name;
+        this.type = type;
         this.fields = fields;
         this.constructor = constructor;
         this.methods = methods;
@@ -117,8 +117,8 @@ public class IntrinsicInterpreterType implements InterpreterType {
     }
 
     @Override
-    public ScalarType getType() {
-        return name;
+    public Type getType() {
+        return type;
     }
 
     @Override
@@ -164,6 +164,6 @@ public class IntrinsicInterpreterType implements InterpreterType {
 
     @Override
     public String toString() {
-        return "IntrinsicInterpreterType<" + name + ">";
+        return "IntrinsicInterpreterType<" + type + ">";
     }
 }
diff --git a/src/main/java/org/zwobble/couscous/interpreter/values/ArrayInterpreterValue.java b/src/main/java/org/zwobble/couscous/interpreter/values/ArrayInterpreterValue.java
new file mode 100644
index 0000000..3a1de58
--- /dev/null
+++ b/src/main/java/org/zwobble/couscous/interpreter/values/ArrayInterpreterValue.java
@@ -0,0 +1,50 @@
+package org.zwobble.couscous.interpreter.values;
+
+import org.zwobble.couscous.interpreter.errors.NoSuchField;
+import org.zwobble.couscous.interpreter.types.InterpreterType;
+import org.zwobble.couscous.interpreter.types.IntrinsicInterpreterType;
+import org.zwobble.couscous.types.Type;
+import org.zwobble.couscous.types.Types;
+import org.zwobble.couscous.values.PrimitiveValue;
+
+import java.util.List;
+import java.util.Optional;
+
+public class ArrayInterpreterValue implements InterpreterValue {
+    private final Type elementType;
+    private final List<InterpreterValue> elements;
+
+    public ArrayInterpreterValue(Type elementType, List<InterpreterValue> elements) {
+        this.elementType = elementType;
+        this.elements = elements;
+    }
+
+    public Type getElementType() {
+        return elementType;
+    }
+
+    public List<InterpreterValue> getElements() {
+        return elements;
+    }
+
+    @Override
+    public InterpreterType getType() {
+        return IntrinsicInterpreterType.builder(ArrayInterpreterValue.class, Types.array(elementType))
+            .build();
+    }
+
+    @Override
+    public Optional<PrimitiveValue> toPrimitiveValue() {
+        return Optional.empty();
+    }
+
+    @Override
+    public InterpreterValue getField(String fieldName) {
+        throw new NoSuchField(fieldName);
+    }
+
+    @Override
+    public void setField(String fieldName, InterpreterValue value) {
+        throw new NoSuchField(fieldName);
+    }
+}
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)));
+    }
 }