unary token support

Author: sidhant92

src/main/java/com/github/sidhant92/boolparser/application/BooleanExpressionEvaluator.java

@@ -11,6 +11,8 @@
 import com.github.sidhant92.boolparser.domain.NumericToken;
 import com.github.sidhant92.boolparser.domain.StringToken;
 import com.github.sidhant92.boolparser.domain.Token;
+import com.github.sidhant92.boolparser.domain.UnaryToken;
+import com.github.sidhant92.boolparser.exception.InvalidUnaryOperand;
 import com.github.sidhant92.boolparser.operator.OperatorService;
 import com.github.sidhant92.boolparser.parser.BoolExpressionParser;
 import io.vavr.control.Try;
@@ -46,6 +48,8 @@ private boolean evaluateToken(final Token token, final Map<String, Object> data)
                 return evaluateNumericRangeToken((NumericRangeToken) token, data);
             case IN:
                 return evaluateInToken((InToken) token, data);
+            case UNARY:
+                return evaluateUnaryToken((UnaryToken) token, data);
             case BOOLEAN:
                 return evaluateBooleanNode((BooleanToken) token, data);
             default:
@@ -90,11 +94,24 @@ private boolean evaluateInToken(final InToken inToken, final Map<String, Object>
         final DataType dataType = inToken.getItems().get(0).getLeft();
         final Object[] values = inToken.getItems()
                 .stream()
-                .map(Pair::getRight)
-                .toArray();
+                .map(Pair::getRight).toArray();
         return operatorService.evaluate(Operator.IN, ContainerDataType.primitive, dataType, fieldData, values);
     }
 
+    private boolean evaluateUnaryToken(final UnaryToken unaryToken, final Map<String, Object> data) {
+        if (unaryToken.getDataType().equals(DataType.BOOLEAN)) {
+            return (boolean) unaryToken.getValue();
+        }
+        if (checkFieldDataMissing(unaryToken.getValue().toString(), data)) {
+            return false;
+        }
+        final Object fieldValue = data.get(unaryToken.getValue().toString());
+        if (!(fieldValue instanceof Boolean)) {
+            throw new InvalidUnaryOperand();
+        }
+        return (boolean) fieldValue;
+    }
+
     private boolean evaluateBooleanNode(final BooleanToken booleanToken, final Map<String, Object> data) {
         switch (booleanToken.getOperator()) {
             case AND:

src/main/java/com/github/sidhant92/boolparser/exception/InvalidUnaryOperand.java

@@ -0,0 +1,8 @@
+package com.github.sidhant92.boolparser.exception;
+
+public class InvalidUnaryOperand extends RuntimeException {
+    @Override
+    public String getMessage() {
+        return "Invalid operand data type in unary expression";
+    }
+}

src/test/java/com/github/sidhant92/boolparser/application/BooleanExpressionEvaluatorTest.java

@@ -4,9 +4,8 @@
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.Optional;
 import org.junit.jupiter.api.Test;
-import com.github.sidhant92.boolparser.parser.BoolExpressionParser;
+import com.github.sidhant92.boolparser.exception.InvalidUnaryOperand;
 import com.github.sidhant92.boolparser.parser.antlr.BoolParser;
 import io.vavr.control.Try;
 
@@ -18,6 +17,33 @@ public class BooleanExpressionEvaluatorTest {
     private final BooleanExpressionEvaluator booleanExpressionEvaluator = new BooleanExpressionEvaluator(new BoolParser());
 
 
+    @Test
+    public void testUnaryExpressionWithField() {
+        final Map<String, Object> data = new HashMap<>();
+        data.put("is_allowed", true);
+        final Try<Boolean> booleanOptional = booleanExpressionEvaluator.evaluate("not is_allowed", data);
+        assertTrue(booleanOptional.isSuccess());
+        assertFalse(booleanOptional.get());
+    }
+
+    @Test
+    public void testUnaryExpressionWithBoolean() {
+        final Map<String, Object> data = new HashMap<>();
+        data.put("is_allowed", true);
+        final Try<Boolean> booleanOptional = booleanExpressionEvaluator.evaluate("not false", data);
+        assertTrue(booleanOptional.isSuccess());
+        assertTrue(booleanOptional.get());
+    }
+
+    @Test
+    public void testInvalidUnaryOperation() {
+        final Map<String, Object> data = new HashMap<>();
+        data.put("is_allowed", 123);
+        final Try<Boolean> booleanOptional = booleanExpressionEvaluator.evaluate("not is_allowed", data);
+        assertTrue(booleanOptional.isFailure());
+        assertTrue(booleanOptional.getCause() instanceof InvalidUnaryOperand);
+    }
+
     @Test
     public void testSimpleTrueCorrectExpression() {
         final Map<String, Object> data = new HashMap<>();