fix bug function endpoints fn construction

A copy-paste error in built in function construction functions meant that the JVM class was incorrect. This produces unexpected results when visitors are invoked because the wrong visitor branch will be called. This doesn't happen in general because `fromNode` produces the correct behavior.

smithy-rules-engine/src/main/java/software/amazon/smithy/rulesengine/language/eval/RuleEvaluator.java

@@ -180,4 +180,4 @@ public Value evaluateCondition(Condition condition) {
         }
         return value;
     }
-}
+}

smithy-rules-engine/src/main/java/software/amazon/smithy/rulesengine/language/stdlib/BooleanEquals.java

@@ -48,8 +48,8 @@ public BooleanEquals(FunctionNode functionNode) {
      * @param right the right hand-side expression.
      * @return the function defining the BooleanEquals of the left and right expressions.
      */
-    public static Function ofExpressions(Expression left, Expression right) {
-        return LibraryFunction.ofExpressions(DEFINITION, left, right);
+    public static BooleanEquals ofExpressions(Expression left, Expression right) {
+        return new BooleanEquals(FunctionNode.ofExpressions(DEFINITION.getId(), left, right));
     }
 
     @Override

smithy-rules-engine/src/main/java/software/amazon/smithy/rulesengine/language/stdlib/StringEquals.java

@@ -49,7 +49,7 @@ public StringEquals(FunctionNode functionNode) {
      * @return a function instance representing the StringEquals comparison.
      */
     public static Function ofExpressions(Expression left, Expression right) {
-        return LibraryFunction.ofExpressions(DEFINITION, left, right);
+        return new StringEquals(FunctionNode.ofExpressions(DEFINITION.getId(), left, right));
     }
 
     @Override

smithy-rules-engine/src/test/java/software/amazon/smithy/rulesengine/language/fn/FunctionOfExprsTest.java

@@ -0,0 +1,69 @@
+package software.amazon.smithy.rulesengine.language.fn;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.List;
+import org.junit.jupiter.api.Test;
+import software.amazon.smithy.rulesengine.language.syntax.expr.Expression;
+import software.amazon.smithy.rulesengine.language.syntax.fn.FunctionDefinition;
+import software.amazon.smithy.rulesengine.language.visit.ExpressionVisitor;
+
+public class FunctionOfExprsTest {
+
+    @Test
+    void boolEquals() {
+        Expression boolEquals = Expression.of(true).equal(true);
+        assertEquals(boolEquals.accept(new ExpectLibFunction()), false);
+        assertEquals(boolEquals.accept(new ExpectBuiltInFunction()), "bool");
+    }
+
+
+    @Test
+    void stringEquals() {
+        Expression stringEquals = Expression.of("asdf").equal("asdf");
+        assertEquals(stringEquals.accept(new ExpectLibFunction()), false);
+        assertEquals(stringEquals.accept(new ExpectBuiltInFunction()), "string");
+    }
+
+    @Test
+    void not() {
+        Expression not = Expression.of("asdf").equal("asdf").not();
+        assertEquals(not.accept(new ExpectLibFunction()), false);
+        assertEquals(not.accept(new ExpectBuiltInFunction()), "not");
+    }
+
+    static class ExpectLibFunction extends ExpressionVisitor.Default<Boolean> {
+        @Override
+        public Boolean visitLibraryFunction(FunctionDefinition fn, List<Expression> args) {
+            return true;
+        }
+
+        @Override
+        public Boolean getDefault() {
+            return false;
+        }
+    }
+
+    static class ExpectBuiltInFunction extends ExpressionVisitor.Default<String> {
+        @Override
+        public String getDefault() {
+            return "other";
+        }
+
+        @Override
+        public String visitBoolEquals(Expression left, Expression right) {
+            return "bool";
+        }
+
+
+        @Override
+        public String visitStringEquals(Expression left, Expression right) {
+            return "string";
+        }
+
+        @Override
+        public String visitNot(Expression not) {
+            return "not";
+        }
+    }
+}