ref(DefaultJavaPrettyPrinter): calculate is the central point for pri…

…nting compilation units (#3233)

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

@@ -1945,9 +1945,7 @@ public <T> void visitCtUnboundVariableReference(CtUnboundVariableReference<T> re
 
 	@Override
 	public String printCompilationUnit(CtCompilationUnit compilationUnit) {
-		reset();
-		applyPreProcessors(compilationUnit);
-		scanCompilationUnit(compilationUnit);
+		calculate(compilationUnit, compilationUnit.getDeclaredTypes());
 		return getResult();
 	}
 
@@ -1958,10 +1956,6 @@ public void applyPreProcessors(CtElement el) {
 		}
 	}
 
-	protected void scanCompilationUnit(CtCompilationUnit compilationUnit) {
-		scan(compilationUnit);
-		}
-
 	@Override
 	public String printPackageInfo(CtPackage pack) {
 		CtCompilationUnit cu = pack.getFactory().CompilationUnit().getOrCreate(pack);
@@ -1992,30 +1986,32 @@ public void reset() {
 
 	@Override
 	public void calculate(CtCompilationUnit sourceCompilationUnit, List<CtType<?>> types) {
+		reset();
 		if (types.isEmpty()) {
-			return;
-		}
-		CtType<?> type = types.get(0);
-		// reset the importsContext to avoid errors with multiple CU
-		if (sourceCompilationUnit == null) {
-			sourceCompilationUnit = type.getFactory().CompilationUnit().getOrCreate(type);
-		}
-		if (type.getPackage() == null) {
-			type.setParent(type.getFactory().Package().getRootPackage());
-		}
-		if (!hasSameTypes(sourceCompilationUnit, types)) {
-			//the provided CU has different types, then these which has to be printed
-			//clone CU and assign it expected types
-			sourceCompilationUnit = sourceCompilationUnit.clone();
-			sourceCompilationUnit.setDeclaredTypes(types);
-		}
-		CtPackageReference packRef = type.getPackage().getReference();
-		if (!packRef.equals(sourceCompilationUnit.getPackageDeclaration().getReference())) {
-			//the type was cloned and moved to different package. Adapt package reference of compilation unit too
-			sourceCompilationUnit.getPackageDeclaration().setReference(packRef);
-		}
-		printCompilationUnit(sourceCompilationUnit);
+			// is package-info.java, we cannot call types.get(0) in the then branch
+		} else {
+			CtType<?> type = types.get(0);
+			if (sourceCompilationUnit == null) {
+				sourceCompilationUnit = type.getFactory().CompilationUnit().getOrCreate(type);
+			}
+			if (type.getPackage() == null) {
+				type.setParent(type.getFactory().Package().getRootPackage());
+			}
+			CtPackageReference packRef = type.getPackage().getReference();
+			if (!packRef.equals(sourceCompilationUnit.getPackageDeclaration().getReference())) {
+				//the type was cloned and moved to different package. Adapt package reference of compilation unit too
+				sourceCompilationUnit.getPackageDeclaration().setReference(packRef);
+			}
+			if (!hasSameTypes(sourceCompilationUnit, types)) {
+				//the provided CU has different types, then these which has to be printed
+				//clone CU and assign it expected types
+				sourceCompilationUnit = sourceCompilationUnit.clone();
+				sourceCompilationUnit.setDeclaredTypes(types);
+			}
 		}
+		applyPreProcessors(sourceCompilationUnit);
+		scan(sourceCompilationUnit);
+	}
 
 	private boolean hasSameTypes(CtCompilationUnit compilationUnit, List<CtType<?>> types) {
 		List<CtTypeReference<?>> cuTypes = compilationUnit.getDeclaredTypeReferences();

src/main/java/spoon/support/sniper/SniperJavaPrettyPrinter.java

@@ -8,6 +8,7 @@
 import java.util.ArrayDeque;
 import java.util.Collections;
 import java.util.Deque;
+import java.util.List;
 
 import spoon.OutputType;
 import spoon.SpoonException;
@@ -17,6 +18,7 @@
 import spoon.reflect.cu.position.NoSourcePosition;
 import spoon.reflect.declaration.CtCompilationUnit;
 import spoon.reflect.declaration.CtElement;
+import spoon.reflect.declaration.CtType;
 import spoon.reflect.path.CtRole;
 import spoon.reflect.visitor.DefaultJavaPrettyPrinter;
 import spoon.reflect.visitor.PrettyPrinter;
@@ -102,15 +104,15 @@ private TokenWriter createTokenWriterListener(TokenWriter tokenWriter) {
 	}
 
 	@Override
-	protected void scanCompilationUnit(CtCompilationUnit compilationUnit) {
+	public void calculate(CtCompilationUnit compilationUnit, List<CtType<?>> types) {
 		//use line separator of origin source file
 		setLineSeparator(detectLineSeparator(compilationUnit.getOriginalSourceCode()));
 		runInContext(new SourceFragmentContextList(mutableTokenWriter,
 				compilationUnit,
 				Collections.singletonList(compilationUnit.getOriginalSourceFragment()),
 				new ChangeResolver(getChangeCollector(), compilationUnit)),
 		() -> {
-			super.scanCompilationUnit(compilationUnit);
+			super.calculate(sourceCompilationUnit, types);;
 		});
 	}
 
@@ -311,7 +313,7 @@ private SourceFragmentPrinter detectCurrentContext(PrinterEvent event) {
 	}
 
 	/**
-	 * scans the `element` which exist on `role` in it's parent
+	 * scans the `element` which exist on `role` in its parent
 	 * @param role {@link CtRole} of `element` in scope of it's parent
 	 * @param element a scanned element
 	 * @param fragment origin source fragment of element
@@ -444,7 +446,7 @@ private void runInContext(SourceFragmentPrinter context, Runnable code) {
 		try {
 			code.run();
 		} finally {
-			// we make sure to remve all contexts that have been pushed so far
+			// we make sure to remove all contexts that have been pushed so far
 			// and we also remove parameter `context`
 			// so that we can leave the sourceFragmentContextStack clean
 			while (true) {