[FIX] removed dependency to com.intellij.psi.PsiElementFactory

Fixes #4

Author: SeeSharpSoft

src/main/java/net/seesharpsoft/intellij/plugins/csv/CsvStructureViewElement.java

@@ -3,12 +3,19 @@
 import com.intellij.ide.structureView.StructureViewTreeElement;
 import com.intellij.ide.util.treeView.smartTree.SortableTreeElement;
 import com.intellij.ide.util.treeView.smartTree.TreeElement;
+import com.intellij.lang.*;
+import com.intellij.lexer.Lexer;
 import com.intellij.navigation.ItemPresentation;
 import com.intellij.navigation.NavigationItem;
+import com.intellij.openapi.project.Project;
 import com.intellij.psi.PsiElement;
-import com.intellij.psi.PsiElementFactory;
 import com.intellij.psi.PsiFile;
+import com.intellij.psi.PsiManager;
 import com.intellij.psi.PsiNamedElement;
+import com.intellij.psi.impl.source.DummyHolder;
+import com.intellij.psi.impl.source.DummyHolderFactory;
+import com.intellij.psi.impl.source.tree.FileElement;
+import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.util.PsiTreeUtil;
 import net.seesharpsoft.intellij.plugins.csv.psi.CsvField;
 import net.seesharpsoft.intellij.plugins.csv.psi.CsvFile;
@@ -85,8 +92,21 @@ public Icon getIcon(boolean unused) {
         return element.getIcon(ICON_FLAG_VISIBILITY);
     }
 
+    // replaces PsiElementFactory.SERVICE.getInstance(element.getProject()).createDummyHolder("<undefined>", CsvTypes.FIELD, null);
+    // https://github.com/SeeSharpSoft/intellij-csv-validator/issues/4
     protected PsiElement createEmptyPsiField() {
-        return PsiElementFactory.SERVICE.getInstance(element.getProject()).createDummyHolder("<undefined>", CsvTypes.FIELD, null);
+        final String text = "<undefined>";
+        final IElementType type = CsvTypes.FIELD;
+        final Project project = this.element.getProject();
+        final PsiManager psiManager = PsiManager.getInstance(project);
+        final DummyHolder dummyHolder = DummyHolderFactory.createHolder(psiManager, null);
+        final FileElement fileElement = dummyHolder.getTreeElement();
+        final ParserDefinition parserDefinition = LanguageParserDefinitions.INSTANCE.forLanguage(CsvLanguage.INSTANCE);
+        final Lexer lexer = parserDefinition.createLexer(project);
+        final PsiBuilder psiBuilder = PsiBuilderFactory.getInstance().createBuilder(project, fileElement, lexer, CsvLanguage.INSTANCE, text);
+        final ASTNode node = parserDefinition.createParser(project).parse(type, psiBuilder);
+        fileElement.rawAddChildren((com.intellij.psi.impl.source.tree.TreeElement)node);
+        return node.getPsi();
     }
 
     public static class File extends CsvStructureViewElement {