fix: improve line preservation mode

src/main/java/spoon/reflect/visitor/DefaultJavaPrettyPrinter.java

@@ -282,7 +282,7 @@ public DefaultJavaPrettyPrinter scan(CtElement e) {
 			context.elementStack.push(e);
 			if (env.isPreserveLineNumbers()) {
 				if (!(e instanceof CtNamedElement)) {
-					printer.adjustPosition(e, sourceCompilationUnit);
+					printer.adjustStartPosition(e);
 				}
 			}
 			e.accept(this);
@@ -436,9 +436,10 @@ public <R> void visitCtBlock(CtBlock<R> block) {
 			}
 		}
 		printer.decTab();
+		printer.adjustEndPosition(block);
 		if (env.isPreserveLineNumbers()) {
 			if (!block.isImplicit()) {
-				printer.write("}");
+				printer.writeTabs().write("}");
 			}
 		} else {
 			printer.writeln().writeTabs();
@@ -528,7 +529,7 @@ public <T> void visitCtClass(CtClass<T> ctClass) {
 		// lst.addAll(elementPrinterHelper.getComments(ctClass, CommentOffset.INSIDE));
 		printer.write(" {").incTab();
 		elementPrinterHelper.writeElementList(ctClass.getTypeMembers());
-		printer.decTab().writeTabs().write("}");
+		printer.adjustEndPosition(ctClass).decTab().writeTabs().write("}");
 		context.popCurrentThis();
 	}
 
@@ -1090,7 +1091,7 @@ public <T> void visitCtInvocation(CtInvocation<T> invocation) {
 
 			elementPrinterHelper.writeActualTypeArguments(invocation);
 			if (env.isPreserveLineNumbers()) {
-				printer.adjustPosition(invocation, sourceCompilationUnit);
+				printer.adjustStartPosition(invocation);
 			}
 			printer.write(invocation.getExecutable().getSimpleName());
 		}
@@ -1161,7 +1162,7 @@ public <T> void visitCtLocalVariable(CtLocalVariable<T> localVariable) {
 			enterCtStatement(localVariable);
 		}
 		if (env.isPreserveLineNumbers()) {
-			printer.adjustPosition(localVariable, sourceCompilationUnit);
+			printer.adjustStartPosition(localVariable);
 		}
 		if (!context.noTypeDecl()) {
 			elementPrinterHelper.writeModifiers(localVariable);
@@ -1183,7 +1184,7 @@ public <T> void visitCtLocalVariableReference(CtLocalVariableReference<T> refere
 	@Override
 	public <T> void visitCtCatchVariable(CtCatchVariable<T> catchVariable) {
 		if (env.isPreserveLineNumbers()) {
-			printer.adjustPosition(catchVariable, sourceCompilationUnit);
+			printer.adjustStartPosition(catchVariable);
 		}
 		elementPrinterHelper.writeModifiers(catchVariable);
 		scan(catchVariable.getType());
@@ -1809,7 +1810,12 @@ public void calculate(CompilationUnit sourceCompilationUnit, List<CtType<?>> typ
 		elementPrinterHelper.writeHeader(types, imports);
 		for (CtType<?> t : types) {
 			scan(t);
-			printer.writeln().writeln().writeTabs();
+			if (!env.isPreserveLineNumbers()) {
+				// saving lines and chars
+				printer.writeln().writeln().writeTabs();
+			} else {
+				printer.adjustEndPosition(t);
+			}
 		}
 	}
 

src/main/java/spoon/reflect/visitor/printer/ElementPrinterHelper.java

@@ -88,7 +88,7 @@ public void writeModifiers(CtModifiable modifiable) {
 	public void visitCtNamedElement(CtNamedElement namedElement, CompilationUnit sourceCompilationUnit) {
 		writeAnnotations(namedElement);
 		if (env.isPreserveLineNumbers()) {
-			printer.adjustPosition(namedElement, sourceCompilationUnit);
+			printer.adjustStartPosition(namedElement);
 		}
 	}
 
@@ -257,7 +257,7 @@ public void writeHeader(List<CtType<?>> types, Collection<CtReference> imports)
 		if (!types.isEmpty()) {
 			for (CtType<?> ctType : types) {
 				writeComment(ctType, CommentOffset.TOP_FILE);
-				printer.writeln().writeln().writeTabs();
+				//printer.writeln().writeln().writeTabs();
 			}
 			// writing the header package
 			if (!types.get(0).getPackage().isUnnamedPackage()) {

src/main/java/spoon/reflect/visitor/printer/PrinterHelper.java

@@ -16,7 +16,6 @@
  */
 package spoon.reflect.visitor.printer;
 
-import org.apache.log4j.Level;
 import spoon.compiler.Environment;
 import spoon.reflect.code.BinaryOperatorKind;
 import spoon.reflect.code.UnaryOperatorKind;
@@ -159,23 +158,30 @@ private boolean isWhite(char c) {
 		return (c == ' ') || (c == '\t') || (c == '\n') || (c == '\r');
 	}
 
-	public void adjustPosition(CtElement e, CompilationUnit unitExpected) {
-		if (e.getPosition() != null && !e.isImplicit() && e.getPosition().getCompilationUnit() != null && e.getPosition().getCompilationUnit() == unitExpected) {
+	public PrinterHelper adjustStartPosition(CtElement e) {
+		if (e.getPosition() != null && !e.isImplicit()) {
+			// we should add some lines
 			while (line < e.getPosition().getLine()) {
 				insertLine();
 			}
+			// trying to remove some lines
 			while (line > e.getPosition().getLine()) {
 				if (!removeLine()) {
-					if (line > e.getPosition().getEndLine()) {
-						final String message = "cannot adjust position of " + e.getClass().getSimpleName() + " '" //
-								+ e.getShortRepresentation() + "' " + " to match lines: " + line + " > [" //
-								+ e.getPosition().getLine() + ", " + e.getPosition().getEndLine() + "]"; //
-						env.report(null, Level.WARN, e, message);
-					}
 					break;
 				}
 			}
 		}
+		return this;
+	}
+
+	public PrinterHelper adjustEndPosition(CtElement e) {
+		if (env.isPreserveLineNumbers() && e.getPosition() != null) {
+			// let's add lines if required
+			while (line < e.getPosition().getEndLine()) {
+				insertLine();
+			}
+		}
+		return this;
 	}
 
 	public void undefineLine() {

src/main/java/spoon/support/compiler/jdt/JDTBasedSpoonCompiler.java

@@ -502,6 +502,7 @@ protected void generateProcessedSourceFilesUsingCUs() {
 
 				IOUtils.copy(is, new FileOutputStream(file));
 
+
 				if (!printedFiles.contains(file)) {
 					printedFiles.add(file);
 				}

src/test/java/spoon/test/prettyprinter/DefaultPrettyPrinterTest.java

@@ -24,6 +24,8 @@
 
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileReader;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
@@ -261,7 +263,7 @@ public void printClassCreatedWithSpoon() throws Exception {
 		File javaFile = new File(pathname);
 		assertTrue(javaFile.exists());
 
-		assertEquals(nl + nl + "package foo;" + nl + nl + nl + "class Bar {}" + nl + nl,
+		assertEquals("package foo;" + nl + nl + nl + "class Bar {}" + nl + nl,
 				IOUtils.toString(new FileInputStream(javaFile), "UTF-8"));
 	}
 
@@ -291,4 +293,5 @@ public void testTernaryParenthesesOnLocalVariable() {
 		snippet = launcher.getFactory().Code().createCodeSnippetStatement(compile.toString());
 		assertEquals(compile, snippet.compile());
 	}
+
 }

src/test/java/spoon/test/prettyprinter/LinesTest.java

@@ -1,14 +1,31 @@
 package spoon.test.prettyprinter;
 
+import org.apache.commons.io.IOUtils;
 import org.junit.Before;
 import org.junit.Test;
 import spoon.Launcher;
 import spoon.compiler.SpoonResourceHelper;
+import spoon.reflect.code.CtThisAccess;
+import spoon.reflect.code.CtTypeAccess;
+import spoon.reflect.declaration.CtElement;
+import spoon.reflect.declaration.CtNamedElement;
 import spoon.reflect.declaration.CtType;
 import spoon.reflect.factory.Factory;
+import spoon.reflect.reference.CtTypeReference;
 import spoon.reflect.visitor.DefaultJavaPrettyPrinter;
+import spoon.reflect.visitor.filter.NameFilter;
+import spoon.reflect.visitor.filter.TypeFilter;
+import spoon.test.prettyprinter.testclasses.QualifiedThisRef;
+
+import java.io.File;
+import java.io.FileReader;
+import java.util.ArrayList;
+import java.util.List;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertTrue;
+import static spoon.test.limits.StaticFieldAccesOnInstance.test;
 
 public class LinesTest {
 
@@ -45,4 +62,50 @@ public void testPrettyPrinterWithLines() throws Exception {
 
 	}
 
+	@Test
+	public void testIdenticalPrettyPrinter() throws  Exception{
+		// contract: the end line should also be preserved
+
+		// setup
+		String[] options = {"--output-type", "compilationunits",
+				"--output", "target/testIdenticalPrettyPrinter",
+				// those three options together are the closest to what the developer wrote
+				"--enable-comments", "--lines", "--with-imports"};
+
+		List<String> paths = new ArrayList<>();
+		paths.add("spoon/test/prettyprinter/testclasses/A.java");
+		paths.add("spoon/test/prettyprinter/testclasses/AClass.java");
+		//paths.add("spoon/test/prettyprinter/testclasses/QualifiedThisRef.java");
+		//paths.add("spoon/test/prettyprinter/testclasses/ImportStatic.java");
+		//paths.add("spoon/test/prettyprinter/testclasses/QualifiedThisRef.java");
+		//paths.add("spoon/test/prettyprinter/testclasses/Rule.java");
+		//paths.add("spoon/test/prettyprinter/testclasses/TypeIdentifierCollision.java");
+
+
+		final Launcher launcher = new Launcher();
+		launcher.setArgs(options);
+		for (String path : paths) {
+			launcher.addInputResource("./src/test/java/" + path);
+		}
+		launcher.run();
+
+		final Launcher launcher2 = new Launcher();
+		launcher2.setArgs(options);
+		for (String path : paths) {
+			launcher2.addInputResource("./target/testIdenticalPrettyPrinter/" + path);
+		}
+		launcher2.run();
+
+		int n=0;
+		List<CtElement> elements = launcher.getModel().getElements(new TypeFilter<>(CtElement.class));
+		for (int i = 0; i < elements.size(); i++) {
+			n++;
+			CtElement e = elements.get(i);
+			CtElement el2 = launcher2.getModel().getElements(new TypeFilter<>(CtElement.class)).get(i);
+			assertNotSame(e, el2);
+			assertEquals(e.toString() + " not handled", e.getPosition().getLine(), el2.getPosition().getLine());
+			assertEquals(e.toString() + " not handled", e.getPosition().getEndLine(), el2.getPosition().getEndLine());
+		}
+		assertTrue(n>20);
+	}
 }

src/test/java/spoon/test/prettyprinter/PrinterTest.java

@@ -79,8 +79,8 @@ public void testFQNModeWriteFQNConstructorInCtVisitor() {
 	@Test
 	public void testAutoimportModeDontImportUselessStatic() {
 		Launcher spoon = new Launcher();
-		PrettyPrinter printer = spoon.createPrettyPrinter();
 		spoon.getEnvironment().setAutoImports(true);
+		PrettyPrinter printer = spoon.createPrettyPrinter();
 		spoon.addInputResource("./src/test/java/spoon/test/prettyprinter/testclasses/ImportStatic.java");
 		spoon.buildModel();