1 files changed, 127 insertions, 0 deletions
diff --git a/javaparser-testing/src/test/java/com/github/javaparser/ast/visitor/ModifierVisitorTest.java b/javaparser-testing/src/test/java/com/github/javaparser/ast/visitor/ModifierVisitorTest.java
new file mode 100644
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+++ b/javaparser-testing/src/test/java/com/github/javaparser/ast/visitor/ModifierVisitorTest.java
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2007-2010 Júlio Vilmar Gesser.
+ * Copyright (C) 2011, 2013-2016 The JavaParser Team.
+ *
+ * This file is part of JavaParser.
+ *
+ * JavaParser can be used either under the terms of
+ * a) the GNU Lesser General Public License as published by
+ *     the Free Software Foundation, either version 3 of the License, or
+ *     (at your option) any later version.
+ * b) the terms of the Apache License
+ *
+ * You should have received a copy of both licenses in LICENCE.LGPL and
+ * LICENCE.APACHE. Please refer to those files for details.
+ *
+ * JavaParser is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ */
+
+package com.github.javaparser.ast.visitor;
+
+import com.github.javaparser.JavaParser;
+import com.github.javaparser.ast.NodeList;
+import com.github.javaparser.ast.body.BodyDeclaration;
+import com.github.javaparser.ast.body.VariableDeclarator;
+import com.github.javaparser.ast.expr.Expression;
+import com.github.javaparser.ast.expr.IntegerLiteralExpr;
+import com.github.javaparser.ast.expr.StringLiteralExpr;
+import org.junit.Test;
+
+import static com.github.javaparser.JavaParser.parseExpression;
+import static com.github.javaparser.utils.Utils.EOL;
+import static org.junit.Assert.assertEquals;
+
+public class ModifierVisitorTest {
+    @Test
+    public void makeSureParentListsCanBeModified() {
+        NodeList<StringLiteralExpr> list = new NodeList<>();
+        list.add(new StringLiteralExpr("t"));
+        list.add(new StringLiteralExpr("a"));
+        list.add(new StringLiteralExpr("b"));
+        list.add(new StringLiteralExpr("c"));
+
+        list.accept(new ModifierVisitor<Void>() {
+            @Override
+            public Visitable visit(final StringLiteralExpr n, final Void arg) {
+                String v = n.getValue();
+
+                list.addFirst(new StringLiteralExpr("extra " + v));
+                list.remove(new StringLiteralExpr("t"));
+
+                if (v.equals("a")) {
+                    return new StringLiteralExpr("x");
+                }
+                if (v.equals("b")) {
+                    return null;
+                }
+
+                return n;
+            }
+        }, null);
+
+        assertEquals("extra c", list.get(0).getValue());
+        assertEquals("extra b", list.get(1).getValue());
+        assertEquals("extra a", list.get(2).getValue());
+        assertEquals("extra t", list.get(3).getValue());
+        assertEquals("x", list.get(4).getValue());
+        assertEquals("c", list.get(5).getValue());
+        assertEquals(6, list.size());
+    }
+
+    @Test
+    public void binaryExprReturnsLeftExpressionWhenRightSideIsRemoved() {
+        Expression expression = parseExpression("1+2");
+        Visitable result = expression.accept(new ModifierVisitor<Void>() {
+            public Visitable visit(IntegerLiteralExpr integerLiteralExpr, Void arg) {
+                if (integerLiteralExpr.getValue().equals("1")) {
+                    return null;
+                }
+                return integerLiteralExpr;
+            }
+        }, null);
+        assertEquals("2", result.toString());
+    }
+
+    @Test
+    public void binaryExprReturnsRightExpressionWhenLeftSideIsRemoved() {
+        final Expression expression = parseExpression("1+2");
+        final Visitable result = expression.accept(new ModifierVisitor<Void>() {
+            public Visitable visit(IntegerLiteralExpr integerLiteralExpr, Void arg) {
+                if (integerLiteralExpr.getValue().equals("2")) {
+                    return null;
+                }
+                return integerLiteralExpr;
+            }
+        }, null);
+        assertEquals("1", result.toString());
+    }
+
+    @Test
+    public void fieldDeclarationCantSurviveWithoutVariables() {
+        final BodyDeclaration<?> bodyDeclaration = JavaParser.parseBodyDeclaration("int x=1;");
+
+        final Visitable result = bodyDeclaration.accept(new ModifierVisitor<Void>() {
+            public Visitable visit(VariableDeclarator x, Void arg) {
+                return null;
+            }
+        }, null);
+
+        assertEquals(null, result);
+    }
+
+    @Test
+    public void variableDeclarationCantSurviveWithoutVariables() {
+        final BodyDeclaration<?> bodyDeclaration = JavaParser.parseBodyDeclaration("void x() {int x=1;}");
+
+        final Visitable result = bodyDeclaration.accept(new ModifierVisitor<Void>() {
+            public Visitable visit(VariableDeclarator x, Void arg) {
+                return null;
+            }
+        }, null);
+
+        assertEquals("void x() {" + EOL + "}", result.toString());
+    }
+}