JEXL-406: exposed TemplateInterpreter.Arguments to allow TemplateInte…

…rpreter derivation (internal, not supported api);

- added test in different package;

src/main/java/org/apache/commons/jexl3/internal/TemplateInterpreter.java

@@ -48,7 +48,7 @@ public class TemplateInterpreter extends Interpreter {
      * Helper ctor.
      * <p>Stores the different properties required to create a Template interpreter.
      */
-    static class Arguments {
+    public static class Arguments {
         /** The engine. */
         Engine jexl;
         /** The options. */
@@ -120,7 +120,7 @@ Arguments writer(final Writer o) {
      * Creates a template interpreter instance.
      * @param args the template interpreter arguments
      */
-    TemplateInterpreter(final Arguments args) {
+    protected TemplateInterpreter(final Arguments args) {
         super(args.jexl, args.options, args.jcontext, args.jframe);
         exprs = args.expressions;
         writer = args.out;
@@ -243,17 +243,11 @@ protected Object visit(final ASTFunctionNode node, final Object data) {
                 if ("include".equals(functionName)) {
                     // evaluate the arguments
                     Object[] argv = visit(argNode, null);
-                    if (argv != null && argv.length > 0) {
-                        if (argv[0] instanceof TemplateScript) {
-                            final TemplateScript script = (TemplateScript) argv[0];
-                            if (argv.length > 1) {
-                                argv = Arrays.copyOfRange(argv, 1, argv.length);
-                            } else {
-                                argv = null;
-                            }
-                            include(script, argv);
-                            return null;
-                        }
+                    if (argv != null && argv.length > 0 && argv[0] instanceof TemplateScript) {
+                        final TemplateScript script = (TemplateScript) argv[0];
+                        argv = argv.length > 1? Arrays.copyOfRange(argv, 1, argv.length) : null;
+                        include(script, argv);
+                        return null;
                     }
                 }
                 // fail safe
@@ -270,24 +264,24 @@ protected Object visit(final ASTJexlScript script, final Object data) {
                 @Override
                 protected Interpreter createInterpreter(final JexlContext context, final Frame local, final JexlOptions options) {
                     final TemplateInterpreter.Arguments targs = new TemplateInterpreter.Arguments(jexl)
-                            .context(context)
-                            .options(options)
-                            .frame(local)
-                            .expressions(exprs)
-                            .writer(writer);
+                        .context(context)
+                        .options(options)
+                        .frame(local)
+                        .expressions(exprs)
+                        .writer(writer);
                     return jexl.createTemplateInterpreter(targs);
                 }
             };
         }
         // otherwise...
         final int numChildren = script.jjtGetNumChildren();
-            Object result = null;
-            for (int i = 0; i < numChildren; i++) {
+        Object result = null;
+        for (int i = 0; i < numChildren; i++) {
             final JexlNode child = script.jjtGetChild(i);
-                result = child.jjtAccept(this, data);
-                cancelCheck(child);
-            }
-            return result;
+            result = child.jjtAccept(this, data);
+            cancelCheck(child);
         }
+        return result;
+    }
 
 }

src/test/java/org/apache/commons/jexl3/Issues400Test.java

@@ -180,7 +180,7 @@ public String join(int[] list, String str) {
   }
 
   @Test
-  public void test406() {
+  public void test406a() {
     final JexlEngine jexl = new JexlBuilder()
         .cache(64)
         .strict(true)

src/test/java/org/example/SomeTest.java

@@ -0,0 +1,108 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.example;
+
+import org.apache.commons.jexl3.JexlArithmetic;
+import org.apache.commons.jexl3.JexlBuilder;
+import org.apache.commons.jexl3.JexlContext;
+import org.apache.commons.jexl3.JexlEngine;
+import org.apache.commons.jexl3.JexlException;
+import org.apache.commons.jexl3.JexlExpression;
+import org.apache.commons.jexl3.JexlOptions;
+import org.apache.commons.jexl3.JexlScript;
+import org.apache.commons.jexl3.MapContext;
+import org.apache.commons.jexl3.internal.Engine;
+import org.apache.commons.jexl3.internal.Frame;
+import org.apache.commons.jexl3.internal.Interpreter;
+import org.apache.commons.jexl3.internal.TemplateEngine;
+import org.apache.commons.jexl3.internal.TemplateInterpreter;
+import org.apache.commons.jexl3.introspection.JexlPermissions;
+import org.apache.commons.jexl3.parser.JexlNode;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class SomeTest {
+
+  public static class MyMath {
+    public double cos(final double x) {
+      return Math.cos(x);
+    }
+  }
+
+  /**
+   * User namespace needs to be allowed through permissions.
+   */
+  @Test
+  public void testCustomFunctionPermissions() {
+      Map<String, Object> funcs = new HashMap<String, Object>();
+      funcs.put("math", new MyMath());
+      JexlPermissions permissions = JexlPermissions.parse("org.example.*");
+      JexlEngine jexl = new JexlBuilder().permissions(permissions).namespaces(funcs).create();
+      JexlContext jc = new MapContext();
+      jc.set("pi", Math.PI);
+      JexlExpression e = jexl.createExpression("math:cos(pi)");
+      Number result = (Number) e.evaluate(jc);
+      Assert.assertEquals(-1, result.intValue());
+  }
+
+  /**
+   * Engine creating dedicated template interpreter.
+   */
+  public static class Engine406 extends Engine {
+    public Engine406(final JexlBuilder conf) {
+      super(conf);
+    }
+    @Override public TemplateInterpreter createTemplateInterpreter(final TemplateInterpreter.Arguments args) {
+      return new TemplateInterpreter406(args);
+    }
+  }
+
+  /** Counting the number of node interpretation calls. */
+  static AtomicInteger CALL406 = new AtomicInteger(0);
+
+  public static class TemplateInterpreter406 extends TemplateInterpreter {
+    protected TemplateInterpreter406(final Arguments args) {
+      super(args);
+    }
+    public Object interpret(final JexlNode node) {
+      CALL406.incrementAndGet();
+      return super.interpret(node);
+    }
+  }
+
+  @Test
+  public void test406b() {
+    final JexlEngine jexl = new JexlBuilder() {
+      @Override
+      public JexlEngine create() {
+        return new Engine406(this);
+      }
+    }.cache(64).strict(true).safe(false).create();
+    String src = "`Call ${x}`";
+    JexlScript script = jexl.createScript(src, "x");
+    Object result = script.execute(null, 406);
+    Assert.assertEquals("Call 406", result);
+    Assert.assertEquals(1, CALL406.get());
+    result = script.execute(null, 42);
+    Assert.assertEquals("Call 42", result);
+    Assert.assertEquals(2, CALL406.get());
+  }
+}