Handle parenthesized sub expressions in Java AST

1 files changed, 77 insertions, 13 deletions

diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/java/JavaWriterTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/java/JavaWriterTests.java
index e1e43ad..25b2c9f 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/java/JavaWriterTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/java/JavaWriterTests.java
@@ -794,7 +794,7 @@ public class JavaWriterTests {
     public void falseLiteral() throws IOException {
         var java = new JavaBooleanLiteral(false);
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("false"));
     }
@@ -803,7 +803,7 @@ public class JavaWriterTests {
     public void trueLiteral() throws IOException {
         var java = new JavaBooleanLiteral(true);
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("true"));
     }
@@ -812,7 +812,7 @@ public class JavaWriterTests {
     public void integerLiteral() throws IOException {
         var java = new JavaIntegerLiteral(42);
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("42"));
     }
@@ -821,7 +821,7 @@ public class JavaWriterTests {
     public void nullLiteral() throws IOException {
         var java = new JavaNullLiteral();
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("null"));
     }
@@ -830,7 +830,7 @@ public class JavaWriterTests {
     public void stringLiteral() throws IOException {
         var java = new JavaStringLiteral("hello");
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("\"hello\""));
     }
@@ -843,7 +843,7 @@ public class JavaWriterTests {
             new JavaIntegerLiteral(42)
         );
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("x = 42"));
     }
@@ -856,7 +856,7 @@ public class JavaWriterTests {
             .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("y")))
             .build();
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("x >>> y"));
     }
@@ -869,7 +869,7 @@ public class JavaWriterTests {
             .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("y")))
             .build();
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("x & y"));
     }
@@ -881,7 +881,7 @@ public class JavaWriterTests {
             JavaIdentifier.of("two")
         );
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("one.two"));
     }
@@ -893,7 +893,7 @@ public class JavaWriterTests {
             JavaIdentifier.of("three")
         );
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("one.Two.three"));
     }
@@ -905,7 +905,7 @@ public class JavaWriterTests {
             JavaIdentifier.of("three")
         );
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("one.Two::three"));
     }
@@ -917,7 +917,7 @@ public class JavaWriterTests {
             List.of(new JavaIntegerLiteral(1), new JavaIntegerLiteral(2))
         );
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("new one.Two(1, 2)"));
     }
@@ -926,12 +926,76 @@ public class JavaWriterTests {
     public void ref() throws IOException {
         var java = new JavaRef(JavaIdentifier.of("x"));
 
-        var string = write(writer -> writer.writeExpression(java));
+        var string = write(writer -> writer.writeTopLevelExpression(java));
 
         assertThat(string, equalTo("x"));
     }
 
     @Test
+    public void whenSubExpressionHasLowerPrecedenceThenSubExpressionIsParenthesized() throws IOException {
+        var java = JavaBinaryOperation.arbitrary()
+            .withOperator(JavaBinaryOperator.BITWISE_AND)
+            .withLeft(
+                JavaBinaryOperation.arbitrary()
+                    .withOperator(JavaBinaryOperator.ASSIGN)
+                    .withLeft(JavaRef.arbitrary().withName(JavaIdentifier.of("x")))
+                    .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("y")))
+            )
+            .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("z")))
+            .build();
+
+        var string = write(writer -> writer.writeTopLevelExpression(java));
+
+        assertThat(string, equalTo("(x = y) & z"));
+    }
+
+    @Test
+    public void whenSubExpressionsOfLeftAssociativeBinaryOperationHaveSamePrecedenceThenRightExpressionIsParenthesized() throws IOException {
+        var java = JavaBinaryOperation.arbitrary()
+            .withOperator(JavaBinaryOperator.BITWISE_AND)
+            .withLeft(
+                JavaBinaryOperation.arbitrary()
+                    .withOperator(JavaBinaryOperator.BITWISE_AND)
+                    .withLeft(JavaRef.arbitrary().withName(JavaIdentifier.of("a")))
+                    .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("b")))
+            )
+            .withRight(
+                JavaBinaryOperation.arbitrary()
+                    .withOperator(JavaBinaryOperator.BITWISE_AND)
+                    .withLeft(JavaRef.arbitrary().withName(JavaIdentifier.of("c")))
+                    .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("d")))
+            )
+            .build();
+
+        var string = write(writer -> writer.writeTopLevelExpression(java));
+
+        assertThat(string, equalTo("a & b & (c & d)"));
+    }
+
+    @Test
+    public void whenSubExpressionsOfRightAssociativeBinaryOperationHaveSamePrecedenceThenLeftExpressionIsParenthesized() throws IOException {
+        var java = JavaBinaryOperation.arbitrary()
+            .withOperator(JavaBinaryOperator.ASSIGN)
+            .withLeft(
+                JavaBinaryOperation.arbitrary()
+                    .withOperator(JavaBinaryOperator.ASSIGN)
+                    .withLeft(JavaRef.arbitrary().withName(JavaIdentifier.of("a")))
+                    .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("b")))
+            )
+            .withRight(
+                JavaBinaryOperation.arbitrary()
+                    .withOperator(JavaBinaryOperator.ASSIGN)
+                    .withLeft(JavaRef.arbitrary().withName(JavaIdentifier.of("c")))
+                    .withRight(JavaRef.arbitrary().withName(JavaIdentifier.of("d")))
+            )
+            .build();
+
+        var string = write(writer -> writer.writeTopLevelExpression(java));
+
+        assertThat(string, equalTo("(a = b) = c = d"));
+    }
+
+    @Test
     public void typeRefWithoutArgsHasNoAngleBrackets() throws IOException {
         var java = JavaTypeRef.topLevel(
             JavaPackageName.of("abc", "def"),