Support reading Java this expressions

2 files changed, 46 insertions, 7 deletions

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 3306dbf..10d6e10 100644
--- a/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java
+++ b/src/main/java/org/zwobble/couscous/frontends/java/JavaReader.java
@@ -14,6 +14,7 @@ import org.eclipse.jdt.core.dom.NumberLiteral;
 import org.eclipse.jdt.core.dom.ReturnStatement;
 import org.eclipse.jdt.core.dom.Statement;
 import org.eclipse.jdt.core.dom.StringLiteral;
+import org.eclipse.jdt.core.dom.ThisExpression;
 import org.eclipse.jdt.core.dom.TypeDeclaration;
 import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.ClassNodeBuilder;
@@ -25,6 +26,7 @@ import org.zwobble.couscous.ast.ReturnNode;
 import org.zwobble.couscous.ast.StatementNode;
 import org.zwobble.couscous.ast.StaticMethodCallNode;
 import org.zwobble.couscous.ast.TernaryConditionalNode;
+import org.zwobble.couscous.ast.ThisReferenceNode;
 import org.zwobble.couscous.ast.TypeName;
 
 import com.google.common.collect.Lists;
@@ -85,6 +87,8 @@ public class JavaReader {
                 return readNumberLiteral((NumberLiteral)expression);
             case ASTNode.STRING_LITERAL:
                 return readStringLiteral((StringLiteral)expression);
+            case ASTNode.THIS_EXPRESSION:
+                return readThisExpression((ThisExpression)expression);
             case ASTNode.METHOD_INVOCATION:
                 return readMethodInvocation((MethodInvocation)expression);
             case ASTNode.CLASS_INSTANCE_CREATION:
@@ -95,7 +99,7 @@ public class JavaReader {
                 throw new RuntimeException("Unsupported expression: " + expression.getClass());
         }
     }
-
+    
     private static ExpressionNode readBooleanLiteral(BooleanLiteral expression) {
         return LiteralNode.literal(expression.booleanValue());
     }
@@ -108,6 +112,11 @@ public class JavaReader {
         return LiteralNode.literal(expression.getLiteralValue());
     }
 
+    private static ExpressionNode readThisExpression(ThisExpression expression) {
+        return ThisReferenceNode.thisReference(
+            TypeName.of(expression.resolveTypeBinding().getQualifiedName()));
+    }
+
     private static ExpressionNode readMethodInvocation(MethodInvocation expression) {
         val methodName = expression.getName().getIdentifier();
         val arguments = readArguments(expression.arguments());
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 cb2a707..ebfe068 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
@@ -3,6 +3,7 @@ package org.zwobble.couscous.tests.frontends.java;
 import java.nio.file.Files;
 
 import org.junit.Test;
+import org.zwobble.couscous.ast.ClassNode;
 import org.zwobble.couscous.ast.ExpressionNode;
 import org.zwobble.couscous.ast.ReturnNode;
 import org.zwobble.couscous.ast.TernaryConditionalNode;
@@ -16,6 +17,7 @@ import static org.zwobble.couscous.ast.ConstructorCallNode.constructorCall;
 import static org.zwobble.couscous.ast.LiteralNode.literal;
 import static org.zwobble.couscous.ast.MethodCallNode.methodCall;
 import static org.zwobble.couscous.ast.StaticMethodCallNode.staticMethodCall;
+import static org.zwobble.couscous.ast.ThisReferenceNode.thisReference;
 import static org.zwobble.couscous.tests.util.ExtraFiles.deleteRecursively;
 
 import lombok.SneakyThrows;
@@ -31,6 +33,13 @@ public class JavaReaderTests {
     }
     
     @Test
+    public void canReadThisReference() {
+        assertEquals(
+            thisReference(TypeName.of("com.example.Example")),
+            readExpressionInInstanceMethod("this"));
+    }
+    
+    @Test
     public void canReadInstanceMethodCalls() {
         assertEquals(
             methodCall(literal("hello"), "startsWith", asList(literal("h")), BooleanValue.REF),
@@ -59,13 +68,36 @@ public class JavaReaderTests {
     }
 
     @SneakyThrows
+    private ExpressionNode readExpressionInInstanceMethod(String expressionSource) {
+        val javaClass =
+            "public Object main() {" +
+            "    return " + expressionSource + ";" +
+            "}";
+        
+        val classNode = readClass(javaClass);
+        val returnStatement = (ReturnNode) classNode.getMethods().get(0).getBody().get(0);
+        return returnStatement.getValue();
+    }
+
+    @SneakyThrows
     private ExpressionNode readExpression(String expressionSource) {
         val javaClass =
+            "public static Object main() {" +
+            "    return " + expressionSource + ";" +
+            "}";
+        
+        val classNode = readClass(javaClass);
+        val returnStatement = (ReturnNode) classNode.getMethods().get(0).getBody().get(0);
+        return returnStatement.getValue();
+    }
+
+    @SneakyThrows
+    private ClassNode readClass(String classBody) {
+
+        val javaClass =
             "package com.example;" +
             "public class Example {" +
-            "    public static Object main() {" +
-            "        return " + expressionSource + ";" +
-            "    }" +
+            classBody +
             "}";
         
         val directoryPath = Files.createTempDirectory(null);
@@ -75,9 +107,7 @@ public class JavaReaderTests {
             Files.write(sourcePath, asList(javaClass));
             
             val reader = new JavaReader();
-            val classNode = reader.readClassFromFile(directoryPath, sourcePath);
-            val returnStatement = (ReturnNode) classNode.getMethods().get(0).getBody().get(0);
-            return returnStatement.getValue();
+            return reader.readClassFromFile(directoryPath, sourcePath);
         } finally {
             deleteRecursively(directoryPath.toFile());
         }