Add Ternary, fix #324

resources/bytecode/javFiles/Ternary.jav

@@ -0,0 +1,9 @@
+import java.lang.Boolean;
+import java.lang.String;
+import java.lang.Integer;
+
+public class Ternary {
+    public main(x) {
+        return x > 10 ? "big" : "small";
+    }
+}

src/main/java/de/dhbwstuttgart/bytecode/Codegen.java

@@ -1108,6 +1108,20 @@ public class Codegen {
             mv.visitInsn(ATHROW);
             break;
         }
+        case TargetTernary ternary: {
+            generate(state, ternary.cond());
+            var iffalse = new Label();
+            var end = new Label();
+            mv.visitJumpInsn(IFEQ, iffalse);
+            generate(state, ternary.iftrue());
+            convertTo(state, ternary.iftrue().type(), ternary.type());
+            mv.visitJumpInsn(GOTO, end);
+            mv.visitLabel(iffalse);
+            generate(state, ternary.iffalse());
+            convertTo(state, ternary.iffalse().type(), ternary.type());
+            mv.visitLabel(end);
+            break;
+        }
         default:
             throw new CodeGenException("Unexpected value: " + expr);
         }

src/main/java/de/dhbwstuttgart/parser/SyntaxTreeGenerator/StatementGenerator.java

@@ -832,7 +832,13 @@ public class StatementGenerator {
     }
 
     private Expression convert(Java17Parser.ConditionalassignexpressionContext expression) {
-        throw new NotImplementedException();
+        return new Ternary(TypePlaceholder.fresh(
+            expression.getStart()),
+            convert(expression.expression(0)),
+            convert(expression.expression(1)),
+            convert(expression.expression(2)),
+            expression.getStart()
+        );
     }
 
     private Expression convert(Java17Parser.OrexpressionContext expression) {

src/main/java/de/dhbwstuttgart/syntaxtree/AbstractASTWalker.java

@@ -332,4 +332,11 @@ public abstract class AbstractASTWalker implements ASTVisitor {
     public void visit(GuardedPattern aGuardedPattern) {
 
     }
+
+    @Override
+    public void visit(Ternary ternary) {
+        ternary.cond.accept(this);
+        ternary.iftrue.accept(this);
+        ternary.iffalse.accept(this);
+    }
 }

src/main/java/de/dhbwstuttgart/syntaxtree/StatementVisitor.java

@@ -80,4 +80,6 @@ public interface StatementVisitor {
     void visit(Literal literal);
 
     void visit(Throw aThrow);
+
+    void visit(Ternary ternary);
 }

src/main/java/de/dhbwstuttgart/syntaxtree/statement/Ternary.java

@@ -0,0 +1,24 @@
+package de.dhbwstuttgart.syntaxtree.statement;
+
+import de.dhbwstuttgart.syntaxtree.StatementVisitor;
+import de.dhbwstuttgart.syntaxtree.type.RefTypeOrTPHOrWildcardOrGeneric;
+import org.antlr.v4.runtime.Token;
+
+public class Ternary extends Expression {
+
+    public final Expression cond;
+    public final Expression iftrue;
+    public final Expression iffalse;
+
+    public Ternary(RefTypeOrTPHOrWildcardOrGeneric type, Expression cond, Expression iftrue, Expression iffalse, Token offset) {
+        super(type, offset);
+        this.cond = cond;
+        this.iftrue = iftrue;
+        this.iffalse = iffalse;
+    }
+
+    @Override
+    public void accept(StatementVisitor visitor) {
+        visitor.visit(this);
+    }
+}

src/main/java/de/dhbwstuttgart/syntaxtree/visual/OutputGenerator.java

@@ -427,6 +427,18 @@ public class OutputGenerator implements ASTVisitor {
         // TODO implement
     }
 
+    @Override
+    public void visit(Ternary ternary) {
+        out.append("(");
+        ternary.cond.accept(this);
+        out.append(" ? ");
+        ternary.iftrue.accept(this);
+        out.append(" : ");
+        ternary.iffalse.accept(this);
+        out.append(")::");
+        ternary.getType().accept(this);
+    }
+
     @Override
     public void visit(Switch switchStmt) {
         out.append("switch(");

src/main/java/de/dhbwstuttgart/target/generate/StatementToTargetExpression.java

@@ -359,6 +359,11 @@ public class StatementToTargetExpression implements ASTVisitor {
         result = new TargetThrow(converter.convert(aThrow.expr));
     }
 
+    @Override
+    public void visit(Ternary ternary) {
+        result = new TargetTernary(converter.convert(ternary.getType()), converter.convert(ternary.cond), converter.convert(ternary.iftrue), converter.convert(ternary.iffalse));
+    }
+
     @Override
     public void visit(Switch switchStmt) {
         var cases = switchStmt.getBlocks().stream().filter(s -> !s.isDefault()).map(converter::convert).toList();

src/main/java/de/dhbwstuttgart/target/generate/TracingStatementVisitor.java

@@ -203,4 +203,11 @@ public abstract class TracingStatementVisitor implements StatementVisitor {
     public void visit(Yield aYield) {
 
     }
+
+    @Override
+    public void visit(Ternary ternary) {
+        ternary.cond.accept(this);
+        ternary.iftrue.accept(this);
+        ternary.iffalse.accept(this);
+    }
 }

src/main/java/de/dhbwstuttgart/target/tree/expression/TargetTernary.java

@@ -2,5 +2,5 @@ package de.dhbwstuttgart.target.tree.expression;
 
 import de.dhbwstuttgart.target.tree.type.TargetType;
 
-public record TargetTernary(TargetType type, TargetExpression cond, TargetExpression ifTrue, TargetExpression ifFalse) implements TargetExpression {
+public record TargetTernary(TargetType type, TargetExpression cond, TargetExpression iftrue, TargetExpression iffalse) implements TargetExpression {
 }

src/main/java/de/dhbwstuttgart/typeinference/typeAlgo/TYPEStmt.java

@@ -488,6 +488,16 @@ public class TYPEStmt implements StatementVisitor {
         aThrow.expr.accept(this);
     }
 
+    @Override
+    public void visit(Ternary ternary) {
+        ternary.cond.accept(this);
+        ternary.iftrue.accept(this);
+        ternary.iffalse.accept(this);
+        constraintsSet.addUndConstraint(new Pair(ternary.cond.getType(), bool, PairOperator.EQUALSDOT));
+        constraintsSet.addUndConstraint(new Pair(ternary.iftrue.getType(), ternary.getType(), PairOperator.SMALLERDOT));
+        constraintsSet.addUndConstraint(new Pair(ternary.iffalse.getType(), ternary.getType(), PairOperator.SMALLERDOT));
+    }
+
     @Override
     public void visit(Return returnExpr) {
         returnExpr.retexpr.accept(this);

src/test/java/TestComplete.java

@@ -916,6 +916,14 @@ public class TestComplete {
         var instance = clazz.getDeclaredConstructor().newInstance();
     }
 
+    @Test
+    public void testTernary() throws Exception {
+        var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Ternary.jav");
+        var clazz = classFiles.get("Ternary");
+        var instance = clazz.getDeclaredConstructor().newInstance();
+        assertEquals(clazz.getDeclaredMethod("main", Integer.class).invoke(instance, 5), "small");
+    }
+
     @Test
     public void testBug122() throws Exception {
         var classFiles = generateClassFiles(new ByteArrayClassLoader(), "Bug122.jav");