Introduce InterfaceNode

26 files changed, 180 insertions, 79 deletions

diff --git a/src/main/java/org/zwobble/couscous/Backend.java b/src/main/java/org/zwobble/couscous/Backend.java
index 4415593..1c68701 100644
--- a/src/main/java/org/zwobble/couscous/Backend.java
+++ b/src/main/java/org/zwobble/couscous/Backend.java
@@ -1,10 +1,10 @@
 package org.zwobble.couscous;
 
+import org.zwobble.couscous.ast.TypeNode;
+
 import java.io.IOException;
 import java.util.List;
 
-import org.zwobble.couscous.ast.ClassNode;
-
 public interface Backend {
-    void compile(List<ClassNode> classes) throws IOException;
+    void compile(List<TypeNode> classes) throws IOException;
 }
diff --git a/src/main/java/org/zwobble/couscous/CouscousCompiler.java b/src/main/java/org/zwobble/couscous/CouscousCompiler.java
index 9c909ac..4822d97 100644
--- a/src/main/java/org/zwobble/couscous/CouscousCompiler.java
+++ b/src/main/java/org/zwobble/couscous/CouscousCompiler.java
@@ -1,12 +1,12 @@
 package org.zwobble.couscous;
 
+import org.zwobble.couscous.ast.TypeNode;
+import org.zwobble.couscous.frontends.java.JavaFrontend;
+
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
 
-import org.zwobble.couscous.ast.ClassNode;
-import org.zwobble.couscous.frontends.java.JavaFrontend;
-
 public class CouscousCompiler {
     private final JavaFrontend frontend;
     private final Backend backend;
@@ -17,7 +17,7 @@ public class CouscousCompiler {
     }
 
     public void compileDirectory(List<Path> sourcePaths, Path path) throws IOException {
-        List<ClassNode> classes = frontend.readSourceDirectory(sourcePaths, path);
+        List<TypeNode> classes = frontend.readSourceDirectory(sourcePaths, path);
         backend.compile(classes);
     }
 
diff --git a/src/main/java/org/zwobble/couscous/ast/ClassNode.java b/src/main/java/org/zwobble/couscous/ast/ClassNode.java
index 0aaa8c1..5d6d5e2 100644
--- a/src/main/java/org/zwobble/couscous/ast/ClassNode.java
+++ b/src/main/java/org/zwobble/couscous/ast/ClassNode.java
@@ -6,7 +6,7 @@ import org.zwobble.couscous.ast.visitors.NodeTransformer;
 import java.util.List;
 import java.util.Set;
 
-public class ClassNode implements Node {
+public class ClassNode implements TypeNode {
     public static ClassNodeBuilder builder(TypeName name) {
         return new ClassNodeBuilder(name);
     }
@@ -45,11 +45,13 @@ public class ClassNode implements Node {
         this.constructor = constructor;
         methods = methodNodes;
     }
-    
+
+    @Override
     public TypeName getName() {
         return name;
     }
 
+    @Override
     public Set<TypeName> getSuperTypes() {
         return superTypes;
     }
@@ -65,7 +67,8 @@ public class ClassNode implements Node {
     public ConstructorNode getConstructor() {
         return constructor;
     }
-    
+
+    @Override
     public List<MethodNode> getMethods() {
         return methods;
     }
diff --git a/src/main/java/org/zwobble/couscous/ast/InterfaceNode.java b/src/main/java/org/zwobble/couscous/ast/InterfaceNode.java
new file mode 100644
index 0000000..09d2d3a
--- /dev/null
+++ b/src/main/java/org/zwobble/couscous/ast/InterfaceNode.java
@@ -0,0 +1,81 @@
+package org.zwobble.couscous.ast;
+
+import org.zwobble.couscous.ast.visitors.NodeMapper;
+
+import java.util.List;
+import java.util.Set;
+
+public class InterfaceNode implements TypeNode {
+    public static InterfaceNode declareInterface(
+        TypeName name,
+        Set<TypeName> superTypes,
+        List<MethodNode> methods)
+    {
+        return new InterfaceNode(name, superTypes, methods);
+    }
+
+    private final TypeName name;
+    private final Set<TypeName> superTypes;
+    private final List<MethodNode> methods;
+
+    private InterfaceNode(
+        TypeName name,
+        Set<TypeName> superTypes,
+        List<MethodNode> methodNodes)
+    {
+        this.name = name;
+        this.superTypes = superTypes;
+        methods = methodNodes;
+    }
+
+    @Override
+    public TypeName getName() {
+        return name;
+    }
+
+    @Override
+    public Set<TypeName> getSuperTypes() {
+        return superTypes;
+    }
+
+    @Override
+    public List<MethodNode> getMethods() {
+        return methods;
+    }
+
+    @Override
+    public <T> T accept(NodeMapper<T> visitor) {
+        // TODO: implement this
+        return null;
+    }
+
+    @Override
+    public String toString() {
+        return "InterfaceNode(" +
+            "name=" + name +
+            ", superTypes=" + superTypes +
+            ", methods=" + methods +
+            ')';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        InterfaceNode that = (InterfaceNode) o;
+
+        if (!name.equals(that.name)) return false;
+        if (!superTypes.equals(that.superTypes)) return false;
+        return methods.equals(that.methods);
+
+    }
+
+    @Override
+    public int hashCode() {
+        int result = name.hashCode();
+        result = 31 * result + superTypes.hashCode();
+        result = 31 * result + methods.hashCode();
+        return result;
+    }
+}
diff --git a/src/main/java/org/zwobble/couscous/ast/TypeNode.java b/src/main/java/org/zwobble/couscous/ast/TypeNode.java
new file mode 100644
index 0000000..9946267
--- /dev/null
+++ b/src/main/java/org/zwobble/couscous/ast/TypeNode.java
@@ -0,0 +1,10 @@
+package org.zwobble.couscous.ast;
+
+import java.util.List;
+import java.util.Set;
+
+public interface TypeNode extends Node {
+    TypeName getName();
+    Set<TypeName> getSuperTypes();
+    List<MethodNode> getMethods();
+}
diff --git a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpBackend.java b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpBackend.java
index 4ae7704..e98a526 100644
--- a/src/main/java/org/zwobble/couscous/backends/csharp/CsharpBackend.java
+++ b/src/main/java/org/zwobble/couscous/backends/csharp/CsharpBackend.java
@@ -4,7 +4,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.common.io.Resources;
 import org.zwobble.couscous.Backend;
-import org.zwobble.couscous.ast.ClassNode;
+import org.zwobble.couscous.ast.TypeNode;
 
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
@@ -30,7 +30,7 @@ public class CsharpBackend implements Backend {
     }
 
     @Override
-    public void compile(List<ClassNode> classes) throws IOException {
+    public void compile(List<TypeNode> classes) throws IOException {
         Files.write(
             directoryPath.resolve("Program.cs"),
             Iterables.concat(
@@ -50,7 +50,7 @@ public class CsharpBackend implements Backend {
         }
     }
 
-    private String compileClass(ClassNode classNode) {
+    private String compileClass(TypeNode classNode) {
         return CsharpSerializer.serialize(CsharpCodeGenerator.generateCode(classNode, namespace));
     }
 }
diff --git a/src/main/java/org/zwobble/couscous/backends/python/PythonBackend.java b/src/main/java/org/zwobble/couscous/backends/python/PythonBackend.java
index 731faeb..096bddd 100644
--- a/src/main/java/org/zwobble/couscous/backends/python/PythonBackend.java
+++ b/src/main/java/org/zwobble/couscous/backends/python/PythonBackend.java
@@ -3,7 +3,7 @@ package org.zwobble.couscous.backends.python;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.Resources;
 import org.zwobble.couscous.Backend;
-import org.zwobble.couscous.ast.ClassNode;
+import org.zwobble.couscous.ast.TypeNode;
 
 import java.io.File;
 import java.io.IOException;
@@ -33,8 +33,8 @@ public class PythonBackend implements Backend {
     }
     
     @Override
-    public void compile(List<ClassNode> classes) throws IOException {
-        for (ClassNode classNode : classes) {
+    public void compile(List<TypeNode> classes) throws IOException {
+        for (TypeNode classNode : classes) {
             compileClass(classNode);
         }
         for (String runtimeFile :  RUNTIME_FILES) {
@@ -53,7 +53,7 @@ public class PythonBackend implements Backend {
         return moduleName.replace(".", File.separator) + ".py";
     }
     
-    private void compileClass(ClassNode classNode) throws IOException {
+    private void compileClass(TypeNode classNode) throws IOException {
         writeModule(
             classNode.getName().getQualifiedName(),
             serialize(generateCode(classNode)));
diff --git a/src/main/java/org/zwobble/couscous/backends/python/PythonCodeGenerator.java b/src/main/java/org/zwobble/couscous/backends/python/PythonCodeGenerator.java
index ef1aca2..2aafcca 100644
--- a/src/main/java/org/zwobble/couscous/backends/python/PythonCodeGenerator.java
+++ b/src/main/java/org/zwobble/couscous/backends/python/PythonCodeGenerator.java
@@ -38,22 +38,24 @@ import static org.zwobble.couscous.backends.python.ast.PythonWhileNode.pythonWhi
 import static org.zwobble.couscous.util.ExtraLists.list;
 
 public class PythonCodeGenerator {
-    public static PythonModuleNode generateCode(ClassNode classNode) {
-        Iterator<PythonImportNode> imports = generateImports(classNode).iterator();
+    public static PythonModuleNode generateCode(TypeNode typeNode) {
+        ClassNode classNode = (ClassNode) typeNode;
+
+        Iterator<PythonImportNode> imports = generateImports(typeNode).iterator();
 
         PythonImportNode internalsImport = pythonImport(
-            importPathToRoot(classNode),
+            importPathToRoot(typeNode),
             list(pythonImportAlias("_couscous")));
 
         PythonFunctionDefinitionNode constructor =
             generateConstructor(classNode.getConstructor());
 
         Iterable<PythonFunctionDefinitionNode> pythonMethods = transform(
-            classNode.getMethods(),
+            typeNode.getMethods(),
             PythonCodeGenerator::generateFunction);
 
         PythonClassNode pythonClass = pythonClass(
-            classNode.getSimpleName(),
+            typeNode.getName().getSimpleName(),
             ImmutableList.copyOf(Iterables.concat(list(constructor), pythonMethods)));
 
         List<PythonStatementNode> staticConstructor =
@@ -66,18 +68,18 @@ public class PythonCodeGenerator {
             staticConstructor.iterator())));
     }
 
-    private static Stream<PythonImportNode> generateImports(ClassNode classNode) {
+    private static Stream<PythonImportNode> generateImports(TypeNode classNode) {
         Set<TypeName> classes = findReferencedClasses(classNode);
         return classes.stream()
             .filter(name -> !name.equals(InternalCouscousValue.REF))
             .map(name -> pythonImport(importPathToRoot(classNode) + name.getQualifiedName(), list(pythonImportAlias(name.getSimpleName()))));
     }
 
-    private static String importPathToRoot(ClassNode classNode) {
+    private static String importPathToRoot(TypeNode classNode) {
         return Strings.repeat(".", packageDepth(classNode) + 1);
     }
 
-    private static int packageDepth(ClassNode classNode) {
+    private static int packageDepth(TypeNode classNode) {
         int depth = 0;
         final java.lang.String qualifiedName = classNode.getName().getQualifiedName();
         for (int index = 0; index < qualifiedName.length(); index++) {
@@ -88,7 +90,7 @@ public class PythonCodeGenerator {
         return depth;
     }
 
-    private static Set<TypeName> findReferencedClasses(ClassNode classNode) {
+    private static Set<TypeName> findReferencedClasses(TypeNode classNode) {
         return NodeStructure.descendantNodes(classNode)
             .flatMap(node -> node.accept(new NodeMapperWithDefault<Stream<TypeName>>(Stream.empty()) {
                 @Override
diff --git a/src/main/java/org/zwobble/couscous/cli/CouscousCli.java b/src/main/java/org/zwobble/couscous/cli/CouscousCli.java
index 561b3f5..8d4fce1 100644
--- a/src/main/java/org/zwobble/couscous/cli/CouscousCli.java
+++ b/src/main/java/org/zwobble/couscous/cli/CouscousCli.java
@@ -3,6 +3,7 @@ package org.zwobble.couscous.cli;
 import org.apache.commons.cli.*;
 import org.zwobble.couscous.Backend;
 import org.zwobble.couscous.ast.ClassNode;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.backends.python.PythonBackend;
 import org.zwobble.couscous.frontends.java.JavaFrontend;
 
@@ -25,7 +26,7 @@ public class CouscousCli {
         CommandLine arguments = parseArguments(rawArguments);
 
         JavaFrontend frontend = new JavaFrontend();
-        List<ClassNode> classNodes = eagerFlatMap(
+        List<TypeNode> classNodes = eagerFlatMap(
             arguments.getArgList(),
             path -> {
                 try {
diff --git a/src/main/java/org/zwobble/couscous/frontends/java/JavaFrontend.java b/src/main/java/org/zwobble/couscous/frontends/java/JavaFrontend.java
index 5ab2678..51df264 100644
--- a/src/main/java/org/zwobble/couscous/frontends/java/JavaFrontend.java
+++ b/src/main/java/org/zwobble/couscous/frontends/java/JavaFrontend.java
@@ -1,10 +1,7 @@
 package org.zwobble.couscous.frontends.java;
 
 import com.google.common.collect.Multimaps;
-import org.zwobble.couscous.ast.ClassNode;
-import org.zwobble.couscous.ast.Node;
-import org.zwobble.couscous.ast.VariableDeclaration;
-import org.zwobble.couscous.ast.VariableNode;
+import org.zwobble.couscous.ast.*;
 
 import java.io.IOException;
 import java.nio.file.Files;
@@ -20,8 +17,8 @@ import static org.zwobble.couscous.util.ExtraLists.flatMap;
 import static org.zwobble.couscous.util.ExtraStreams.toStream;
 
 public class JavaFrontend {
-    public List<ClassNode> readSourceDirectory(List<Path> sourcePaths, Path directoryPath) throws IOException {
-        List<ClassNode> classNodes = flatMap(
+    public List<TypeNode> readSourceDirectory(List<Path> sourcePaths, Path directoryPath) throws IOException {
+        List<TypeNode> classNodes = flatMap(
             findJavaFiles(directoryPath),
             javaFile -> JavaReader.readClassFromFile(sourcePaths, javaFile));
         ensureDeclarationsAreUnique(classNodes);
@@ -33,7 +30,7 @@ public class JavaFrontend {
             .filter(path -> path.toFile().isFile() && path.toString().endsWith(".java"));
     }
 
-    private void ensureDeclarationsAreUnique(List<ClassNode> classNodes) {
+    private void ensureDeclarationsAreUnique(List<TypeNode> classNodes) {
         List<VariableDeclaration> declarations = eagerFlatMap(classNodes, this::findDeclarations);
         Multimaps.index(declarations, VariableDeclaration::getId)
             .asMap()
diff --git a/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java b/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java
index c85b4fb..6e7f3fc 100644
--- a/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java
+++ b/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java
@@ -37,7 +37,7 @@ import static org.zwobble.couscous.frontends.java.JavaTypes.*;
 import static org.zwobble.couscous.util.ExtraLists.*;
 
 public class JavaReader {
-    public static List<ClassNode> readClassFromFile(List<Path> sourcePaths, Path sourcePath) throws IOException {
+    public static List<TypeNode> readClassFromFile(List<Path> sourcePaths, Path sourcePath) throws IOException {
         CompilationUnit ast = new JavaParser().parseCompilationUnit(sourcePaths, sourcePath);
 
         ImmutableList<IProblem> errors = ImmutableList.copyOf(filter(asList(ast.getProblems()), problem -> problem.isError()));
@@ -58,7 +58,7 @@ public class JavaReader {
             error.getMessage();
     }
 
-    private final ImmutableList.Builder<ClassNode> classes;
+    private final ImmutableList.Builder<TypeNode> classes;
     private int anonymousClassCount = 0;
 
     private JavaReader() {
diff --git a/src/main/java/org/zwobble/couscous/interpreter/JavaProject.java b/src/main/java/org/zwobble/couscous/interpreter/JavaProject.java
index bcb4db6..8038ce1 100644
--- a/src/main/java/org/zwobble/couscous/interpreter/JavaProject.java
+++ b/src/main/java/org/zwobble/couscous/interpreter/JavaProject.java
@@ -3,6 +3,7 @@ package org.zwobble.couscous.interpreter;
 import java.util.List;
 
 import org.zwobble.couscous.ast.ClassNode;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.interpreter.values.BoxedIntegerInterpreterValue;
 import org.zwobble.couscous.interpreter.values.ConcreteType;
 import org.zwobble.couscous.interpreter.values.InternalCouscousInterpreterValue;
@@ -20,7 +21,7 @@ public class JavaProject {
             .addClass(BoxedIntegerInterpreterValue.TYPE);
     }
 
-    public static Project of(List<ClassNode> classNodes) {
+    public static Project of(List<TypeNode> classNodes) {
         Iterable<ConcreteType> concreteTypes = Iterables.transform(classNodes, ConcreteType::fromNode);
         return builder()
                 .addClasses(concreteTypes)
diff --git a/src/main/java/org/zwobble/couscous/interpreter/values/ConcreteType.java b/src/main/java/org/zwobble/couscous/interpreter/values/ConcreteType.java
index cf48d3c..98036f1 100644
--- a/src/main/java/org/zwobble/couscous/interpreter/values/ConcreteType.java
+++ b/src/main/java/org/zwobble/couscous/interpreter/values/ConcreteType.java
@@ -91,13 +91,21 @@ public class ConcreteType {
         }
     }
     
-    public static ConcreteType fromNode(ClassNode classNode) {
+    public static ConcreteType fromNode(TypeNode typeNode) {
+        ClassNode classNode = (ClassNode)typeNode;
         Map<String, FieldDeclarationNode> fields = classNode.getFields().stream()
             .collect(toMap(
                 field -> field.getName(),
                 field -> field));
-        MethodValue constructor = new MethodValue(getArgumentTypes(classNode.getConstructor().getArguments()), (environment, arguments) -> Executor.callMethod(environment, classNode.getConstructor(), Optional.of(arguments.getReceiver()), arguments.getPositionalArguments()));
-        Map<MethodSignature, MethodValue> methods = classNode.getMethods()
+        MethodValue constructor = new MethodValue(
+            getArgumentTypes(classNode.getConstructor().getArguments()),
+            (environment, arguments) -> Executor.callMethod(
+                environment,
+                classNode.getConstructor(),
+                Optional.of(arguments.getReceiver()),
+                arguments.getPositionalArguments()));
+
+        Map<MethodSignature, MethodValue> methods = typeNode.getMethods()
             .stream()
             .filter(method -> !method.isStatic())
             .collect(toMap(method -> method.signature(), method -> {
@@ -106,7 +114,7 @@ public class ConcreteType {
                     return Executor.callMethod(environment, method, Optional.of(arguments.getReceiver()), arguments.getPositionalArguments());
                 });
             }));
-        Map<MethodSignature, StaticMethodValue> staticMethods = classNode.getMethods()
+        Map<MethodSignature, StaticMethodValue> staticMethods = typeNode.getMethods()
             .stream()
             .filter(method -> method.isStatic())
             .collect(toMap(method -> method.signature(), method -> {
@@ -116,8 +124,8 @@ public class ConcreteType {
                 });
             }));
         return new ConcreteType(
-            classNode.getName(),
-            classNode.getSuperTypes(),
+            typeNode.getName(),
+            typeNode.getSuperTypes(),
             fields,
             classNode.getStaticConstructor(),
             constructor,
diff --git a/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java b/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
index 9914093..2544c4a 100644
--- a/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
@@ -249,6 +249,6 @@ public abstract class BackendEvalTests {
     }
     
     protected abstract PrimitiveValue evalExpression(
-        List<ClassNode> classes,
+        List<TypeNode> classes,
         ExpressionNode expression);
 }
diff --git a/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java b/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
index 5a6ada1..9fa9625 100644
--- a/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
@@ -3,6 +3,7 @@ package org.zwobble.couscous.tests;
 import com.google.common.collect.ImmutableList;
 import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.frontends.java.JavaFrontend;
 import org.zwobble.couscous.interpreter.Interpreter;
 import org.zwobble.couscous.interpreter.JavaProject;
@@ -28,7 +29,7 @@ public class JavaToInterpreterTests extends CompilerTests {
         TypeName returnType
     ) throws IOException, InterruptedException {
         JavaFrontend frontend = new JavaFrontend();
-        List<ClassNode> classNodes = frontend.readSourceDirectory(list(directory), directory);
+        List<TypeNode> classNodes = frontend.readSourceDirectory(list(directory), directory);
 
         Project project = JavaProject.of(classNodes);
         Interpreter interpreter = new Interpreter(project);
diff --git a/src/test/java/org/zwobble/couscous/tests/MethodRunner.java b/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
index 54ae4b5..8fde77f 100644
--- a/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
@@ -11,12 +11,12 @@ import static org.zwobble.couscous.util.ExtraLists.list;
 
 public interface MethodRunner {
     PrimitiveValue runMethod(
-        List<ClassNode> classNodes,
+        List<TypeNode> classNodes,
         TypeName className,
         String methodName,
         List<PrimitiveValue> arguments, TypeName returnType);
 
-    default PrimitiveValue evalExpression(List<ClassNode> classes, ExpressionNode expression) {
+    default PrimitiveValue evalExpression(List<TypeNode> classes, ExpressionNode expression) {
         ClassNode programNode = ClassNode.builder("Program")
             .method(MethodNode.staticMethod("run")
                 .returns(expression.getType())
diff --git a/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java b/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
index ce8ab87..e30f1ef 100644
--- a/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
@@ -51,6 +51,7 @@ public class ValueObjectTests {
             {FormalArgumentNode.class},
             {IfStatementNode.class},
             {InstanceReceiver.class},
+            {InterfaceNode.class},
             {LiteralNode.class},
             {LocalVariableDeclarationNode.class},
             {MethodCallNode.class},
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpCompilerEvalTests.java b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpCompilerEvalTests.java
index ddbee66..995a9d2 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpCompilerEvalTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpCompilerEvalTests.java
@@ -2,6 +2,7 @@ package org.zwobble.couscous.tests.backends.csharp;
 
 import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.ExpressionNode;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.tests.BackendEvalTests;
 import org.zwobble.couscous.values.PrimitiveValue;
 
@@ -9,7 +10,7 @@ import java.util.List;
 
 public class CsharpCompilerEvalTests extends BackendEvalTests {
     @Override
-    protected PrimitiveValue evalExpression(List<ClassNode> classes, ExpressionNode expression) {
+    protected PrimitiveValue evalExpression(List<TypeNode> classes, ExpressionNode expression) {
         return new CsharpMethodRunner().evalExpression(classes, expression);
     }
 }
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
index 88cce22..4e05266 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
@@ -4,10 +4,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterators;
 import org.hamcrest.Matchers;
 import org.zwobble.couscous.Backend;
-import org.zwobble.couscous.ast.ClassNode;
-import org.zwobble.couscous.ast.LiteralNode;
-import org.zwobble.couscous.ast.MethodSignature;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.*;
 import org.zwobble.couscous.backends.Names;
 import org.zwobble.couscous.backends.csharp.CsharpBackend;
 import org.zwobble.couscous.backends.csharp.CsharpSerializer;
@@ -36,7 +33,7 @@ public class CsharpMethodRunner implements MethodRunner {
     private static final String NAMESPACE = "Couscous";
 
     @Override
-    public PrimitiveValue runMethod(List<ClassNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
+    public PrimitiveValue runMethod(List<TypeNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
         try {
             Path directoryPath = Files.createTempDirectory(null);
             Backend compiler = new CsharpBackend(directoryPath, NAMESPACE);
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonCompilerEvalTests.java b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonCompilerEvalTests.java
index e4ff1cb..d87bbb7 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonCompilerEvalTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonCompilerEvalTests.java
@@ -1,7 +1,7 @@
 package org.zwobble.couscous.tests.backends.python;
 
-import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.ExpressionNode;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.tests.BackendEvalTests;
 import org.zwobble.couscous.values.PrimitiveValue;
 
@@ -9,7 +9,7 @@ import java.util.List;
 
 public class PythonCompilerEvalTests extends BackendEvalTests {
     @Override
-    protected PrimitiveValue evalExpression(List<ClassNode> classes, ExpressionNode expression) {
+    protected PrimitiveValue evalExpression(List<TypeNode> classes, ExpressionNode expression) {
         return new PythonMethodRunner().evalExpression(classes, expression);
     }
 }
\ No newline at end of file
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
index a4a57d1..2b0d2ce 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
@@ -2,9 +2,9 @@ package org.zwobble.couscous.tests.backends.python;
 
 import com.google.common.base.Joiner;
 import org.hamcrest.Matchers;
-import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.MethodSignature;
 import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.backends.Names;
 import org.zwobble.couscous.backends.python.PythonBackend;
 import org.zwobble.couscous.backends.python.PythonCodeGenerator;
@@ -28,7 +28,7 @@ import static org.zwobble.couscous.values.PrimitiveValues.value;
 
 public class PythonMethodRunner implements MethodRunner {
     @Override
-    public PrimitiveValue runMethod(List<ClassNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
+    public PrimitiveValue runMethod(List<TypeNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
         try {
             Path directoryPath = Files.createTempDirectory(null);
             PythonBackend compiler = new PythonBackend(directoryPath, "couscous");
diff --git a/src/test/java/org/zwobble/couscous/tests/frontends/java/InnerTypeReadingTests.java b/src/test/java/org/zwobble/couscous/tests/frontends/java/InnerTypeReadingTests.java
index e11b2a1..952bf9d 100644
--- a/src/test/java/org/zwobble/couscous/tests/frontends/java/InnerTypeReadingTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/frontends/java/InnerTypeReadingTests.java
@@ -4,55 +4,55 @@ import org.junit.Test;
 
 import static org.junit.Assert.assertEquals;
 import static org.zwobble.couscous.tests.frontends.java.JavaReading.generateMethodSource;
-import static org.zwobble.couscous.tests.frontends.java.JavaReading.readClasses;
+import static org.zwobble.couscous.tests.frontends.java.JavaReading.readTypes;
 
 public class InnerTypeReadingTests {
     @Test
     public void lambdaWithNoArgumentsAndExpressionBodyIsReadAsAnonymousClassCreation() {
         assertEquals(
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Supplier<Integer> supplier = new java.util.function.Supplier<Integer>() {\n" +
                     "    public Integer get() {\n" +
                     "        return 42;\n" +
                     "    }\n" +
                     "};")),
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Supplier<Integer> supplier = () -> 42;")));
     }
 
     @Test
     public void lambdaWithNoArgumentsAndBlockBodyIsReadAsAnonymousClassCreation() {
         assertEquals(
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Supplier<Integer> supplier = () -> 42;")),
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Supplier<Integer> supplier = () -> { return 42; };")));
     }
 
     @Test
     public void lambdaWithInferredArgumentsAndBlockBodyIsReadAsAnonymousClassCreation() {
         assertEquals(
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Function<Integer, Integer> function = x -> x;")),
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Function<Integer, Integer> function = (Integer x) -> x;")));
     }
 
     @Test
     public void expressionMethodReferenceWithStaticReceiverIsReadAsLambda() {
         assertEquals(
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Function<String, Integer> function = arg0 -> Integer.parseInt(arg0);")),
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "java.util.function.Function<String, Integer> function = Integer::parseInt;")));
     }
 
     @Test
     public void expressionMethodReferenceWithInstanceReceiverIsReadAsLambda() {
         assertEquals(
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "Integer x = 0; java.util.function.Supplier<String> function = () -> x.toString();")),
-            readClasses(generateMethodSource("void",
+            readTypes(generateMethodSource("void",
                 "Integer x = 0; java.util.function.Supplier<String> function = x::toString;")));
     }
 }
diff --git a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
index 442e5fa..dc5965a 100644
--- a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
@@ -18,7 +18,8 @@ import static org.zwobble.couscous.ast.IfStatementNode.ifStatement;
 import static org.zwobble.couscous.ast.LiteralNode.literal;
 import static org.zwobble.couscous.ast.LocalVariableDeclarationNode.localVariableDeclaration;
 import static org.zwobble.couscous.ast.MethodCallNode.staticMethodCall;
-import static org.zwobble.couscous.ast.Operations.*;
+import static org.zwobble.couscous.ast.Operations.boxInt;
+import static org.zwobble.couscous.ast.Operations.integerAdd;
 import static org.zwobble.couscous.ast.ReturnNode.returns;
 import static org.zwobble.couscous.ast.ThisReferenceNode.thisReference;
 import static org.zwobble.couscous.ast.TypeCoercionNode.typeCoercion;
diff --git a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReading.java b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReading.java
index 5c37dbf..408694c 100644
--- a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReading.java
+++ b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReading.java
@@ -1,9 +1,6 @@
 package org.zwobble.couscous.tests.frontends.java;
 
-import org.zwobble.couscous.ast.ClassNode;
-import org.zwobble.couscous.ast.ExpressionNode;
-import org.zwobble.couscous.ast.ReturnNode;
-import org.zwobble.couscous.ast.StatementNode;
+import org.zwobble.couscous.ast.*;
 import org.zwobble.couscous.frontends.java.JavaReader;
 
 import java.nio.file.Files;
@@ -51,17 +48,17 @@ public class JavaReading {
     }
 
     static ClassNode readClass(String classBody) {
-        List<ClassNode> classes = readClasses(classBody);
+        List<TypeNode> classes = readTypes(classBody);
         assertThat(classes, hasSize(1));
-        return classes.get(0);
+        return (ClassNode)classes.get(0);
     }
 
-    static List<ClassNode> readClasses(String classBody) {
+    static List<TypeNode> readTypes(String classBody) {
         String javaClass = generateClassSource(classBody);
         return readSource("com/example/Example.java", javaClass);
     }
 
-    private static List<ClassNode> readSource(String path, String contents) {
+    static List<TypeNode> readSource(String path, String contents) {
         try {
             Path directoryPath = Files.createTempDirectory(null);
             try {
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 b2b572d..fde8646 100644
--- a/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
@@ -236,7 +236,7 @@ public class EvaluatorTests extends BackendEvalTests {
 
     @Override
     protected PrimitiveValue evalExpression(
-            List<ClassNode> classes,
+            List<TypeNode> classes,
             ExpressionNode expression) {
         
         Environment environment = new Environment(
diff --git a/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java b/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
index 499d18c..c8dd2fb 100644
--- a/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
@@ -105,7 +105,7 @@ public class InterpreterMethodTests extends BackendMethodTests {
         return new MethodRunner() {
             @Override
             public PrimitiveValue runMethod(
-                List<ClassNode> classNodes,
+                List<TypeNode> classNodes,
                 TypeName className,
                 String methodName,
                 List<PrimitiveValue> arguments,