361: Adds input constraints to asin and asinr functions (#363)

ezylang · Mar 19, 2023 · f0d2e63 · f0d2e63
1 parent c3558c8
commit f0d2e63
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Showing 3 changed files with 69 additions and 4 deletions.
diff --git a/src/main/java/com/ezylang/evalex/functions/trigonometric/AsinFunction.java b/src/main/java/com/ezylang/evalex/functions/trigonometric/AsinFunction.java
@@ -15,20 +15,38 @@
 */
 package com.ezylang.evalex.functions.trigonometric;
 
+import static java.math.BigDecimal.ONE;
+import static java.math.BigDecimal.valueOf;
+
+import com.ezylang.evalex.EvaluationException;
 import com.ezylang.evalex.Expression;
 import com.ezylang.evalex.data.EvaluationValue;
 import com.ezylang.evalex.functions.AbstractFunction;
 import com.ezylang.evalex.functions.FunctionParameter;
 import com.ezylang.evalex.parser.Token;
+import java.math.BigDecimal;
 
 /** Returns the arc-sine (in degrees). */
 @FunctionParameter(name = "value")
 public class AsinFunction extends AbstractFunction {
+
+  private static final BigDecimal MINUS_ONE = valueOf(-1);
+
   @Override
   public EvaluationValue evaluate(
-      Expression expression, Token functionToken, EvaluationValue... parameterValues) {
+      Expression expression, Token functionToken, EvaluationValue... parameterValues)
+      throws EvaluationException {
+
+    BigDecimal parameterValue = parameterValues[0].getNumberValue();
 
-    return expression.convertDoubleValue(
-        Math.toDegrees(Math.asin(parameterValues[0].getNumberValue().doubleValue())));
+    if (parameterValue.compareTo(ONE) > 0) {
+      throw new EvaluationException(
+          functionToken, "Illegal asin(x) for x > 1: x = " + parameterValue);
+    }
+    if (parameterValue.compareTo(MINUS_ONE) < 0) {
+      throw new EvaluationException(
+          functionToken, "Illegal asin(x) for x < -1: x = " + parameterValue);
+    }
+    return expression.convertDoubleValue(Math.toDegrees(Math.asin(parameterValue.doubleValue())));
   }
 }
diff --git a/src/main/java/com/ezylang/evalex/functions/trigonometric/AsinRFunction.java b/src/main/java/com/ezylang/evalex/functions/trigonometric/AsinRFunction.java
@@ -15,19 +15,38 @@
 */
 package com.ezylang.evalex.functions.trigonometric;
 
+import static java.math.BigDecimal.ONE;
+import static java.math.BigDecimal.valueOf;
+
+import com.ezylang.evalex.EvaluationException;
 import com.ezylang.evalex.Expression;
 import com.ezylang.evalex.data.EvaluationValue;
 import com.ezylang.evalex.functions.AbstractFunction;
 import com.ezylang.evalex.functions.FunctionParameter;
 import com.ezylang.evalex.parser.Token;
+import java.math.BigDecimal;
 
 /** Returns the arc-sine (in radians). */
 @FunctionParameter(name = "value")
 public class AsinRFunction extends AbstractFunction {
+
+  private static final BigDecimal MINUS_ONE = valueOf(-1);
+
   @Override
   public EvaluationValue evaluate(
-      Expression expression, Token functionToken, EvaluationValue... parameterValues) {
+      Expression expression, Token functionToken, EvaluationValue... parameterValues)
+      throws EvaluationException {
+
+    BigDecimal parameterValue = parameterValues[0].getNumberValue();
 
+    if (parameterValue.compareTo(ONE) > 0) {
+      throw new EvaluationException(
+          functionToken, "Illegal asinr(x) for x > 1: x = " + parameterValue);
+    }
+    if (parameterValue.compareTo(MINUS_ONE) < 0) {
+      throw new EvaluationException(
+          functionToken, "Illegal asinr(x) for x < -1: x = " + parameterValue);
+    }
     return expression.convertDoubleValue(
         Math.asin(parameterValues[0].getNumberValue().doubleValue()));
   }

diff --git a/src/test/java/com/ezylang/evalex/functions/trigonometric/TrigonometricFunctionsTest.java b/src/test/java/com/ezylang/evalex/functions/trigonometric/TrigonometricFunctionsTest.java
@@ -135,6 +135,20 @@ void testAsin(String expression, String expectedResult)
     assertExpressionHasExpectedResult(expression, expectedResult);
   }
 
+  @Test
+  void testAsinThrowsExceptionPositive() {
+    assertThatThrownBy(() -> new Expression("ASIN(1.5)").evaluate())
+        .isInstanceOf(EvaluationException.class)
+        .hasMessage("Illegal asin(x) for x > 1: x = 1.5");
+  }
+
+  @Test
+  void testAsinThrowsExceptionNegative() {
+    assertThatThrownBy(() -> new Expression("ASIN(-1.5)").evaluate())
+        .isInstanceOf(EvaluationException.class)
+        .hasMessage("Illegal asin(x) for x < -1: x = -1.5");
+  }
+
   @ParameterizedTest
   @CsvSource(
       delimiter = ':',
@@ -161,6 +175,20 @@ void testAsinR(String expression, String expectedResult)
     assertExpressionHasExpectedResult(expression, expectedResult);
   }
 
+  @Test
+  void testAsinRThrowsExceptionPositive() {
+    assertThatThrownBy(() -> new Expression("ASINR(1.5)").evaluate())
+        .isInstanceOf(EvaluationException.class)
+        .hasMessage("Illegal asinr(x) for x > 1: x = 1.5");
+  }
+
+  @Test
+  void testAsinRThrowsExceptionNegative() {
+    assertThatThrownBy(() -> new Expression("ASINR(-1.5)").evaluate())
+        .isInstanceOf(EvaluationException.class)
+        .hasMessage("Illegal asinr(x) for x < -1: x = -1.5");
+  }
+
   @ParameterizedTest
   @CsvSource(
       delimiter = ':',