refactor: getDocComment uses the same implementation as pretty-printer

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

@@ -19,15 +19,18 @@
 import spoon.reflect.code.CtComment;
 import spoon.reflect.code.CtJavaDoc;
 import spoon.reflect.code.CtJavaDocTag;
+import spoon.support.Internal;
 
 import java.util.Collection;
 import java.util.List;
+import java.util.function.Function;
 import java.util.regex.Pattern;
 
 /**
  * Computes source code representation of the Comment literal
  */
-class CommentHelper {
+@Internal
+public class CommentHelper {
 
 	/**
 	 * RegExp which matches all possible line separators
@@ -37,15 +40,19 @@ class CommentHelper {
 	private CommentHelper() {
 	}
 
-	static void printComment(PrinterHelper printer, CtComment comment) {
-		List<CtJavaDocTag> tags = null;
-		if (comment instanceof CtJavaDoc) {
-			tags = ((CtJavaDoc) comment).getTags();
-		}
-		printComment(printer, comment.getCommentType(), comment.getContent(), tags);
+	/** returns a pretty-printed version of a comment, with prefix, suffix, and intermediate prefix for block and Javadoc */
+	public static String printComment(CtComment comment) {
+		PrinterHelper ph = new PrinterHelper(comment.getFactory().getEnvironment());
+		// now we only use one single method to print all tags
+		printCommentContent(ph, comment, s -> { return  s; });
+		return ph.toString();
 	}
 
-	static void printComment(PrinterHelper printer, CtComment.CommentType commentType, String content, Collection<CtJavaDocTag> javaDocTags) {
+
+	static void printComment(PrinterHelper printer, CtComment comment) {
+		CtComment.CommentType commentType = comment.getCommentType();
+		String content = comment.getContent();
+		// prefix
 		switch (commentType) {
 		case FILE:
 			printer.write(DefaultJavaPrettyPrinter.JAVADOC_START).writeln();
@@ -60,34 +67,16 @@ static void printComment(PrinterHelper printer, CtComment.CommentType commentTyp
 			printer.write(DefaultJavaPrettyPrinter.BLOCK_COMMENT_START);
 			break;
 		}
+		// content
 		switch (commentType) {
 			case INLINE:
 				printer.write(content);
 				break;
 			default:
-				String[] lines = LINE_SEPARATORS_RE.split(content);
-				for (String com : lines) {
-					if (commentType == CtComment.CommentType.BLOCK) {
-						printer.write(com);
-						if (lines.length > 1) {
-							printer.writeln();
-						}
-					} else {
-						if (!com.isEmpty()) {
-							printer.write(DefaultJavaPrettyPrinter.COMMENT_STAR + com).writeln();
-						} else {
-							printer.write(" *" /* no trailing space */ + com).writeln();
-						}
-					}
-				}
-				if (javaDocTags != null && javaDocTags.isEmpty() == false) {
-					printer.write(" *").writeln();
-					for (CtJavaDocTag docTag : javaDocTags) {
-						printJavaDocTag(printer, docTag);
-					}
-				}
-				break;
+				// per line suffix
+				printCommentContent(printer, comment, s -> { return (" * " + s).replaceAll(" *$", ""); });
 		}
+		// suffix
 		switch (commentType) {
 			case BLOCK:
 				printer.write(DefaultJavaPrettyPrinter.BLOCK_COMMENT_END);
@@ -101,9 +90,34 @@ static void printComment(PrinterHelper printer, CtComment.CommentType commentTyp
 		}
 	}
 
-	static void printJavaDocTag(PrinterHelper printer, CtJavaDocTag docTag) {
-		printer.write(DefaultJavaPrettyPrinter.COMMENT_STAR);
-		printer.write(CtJavaDocTag.JAVADOC_TAG_PREFIX);
+	static void printCommentContent(PrinterHelper printer, CtComment comment, Function<String, String> transfo) {
+		CtComment.CommentType commentType = comment.getCommentType();
+		String content = comment.getContent();
+		String[] lines = LINE_SEPARATORS_RE.split(content);
+		for (String com : lines) {
+			if (commentType == CtComment.CommentType.BLOCK) {
+				printer.write(com);
+				if (lines.length > 1) {
+					printer.write(CtComment.LINE_SEPARATOR);
+				}
+			} else {
+				printer.write(transfo.apply(com)).writeln(); // removing spaces at the end of the space
+			}
+		}
+		if (comment instanceof CtJavaDoc) {
+			List<CtJavaDocTag> tags = null;
+			Collection<CtJavaDocTag> javaDocTags = ((CtJavaDoc) comment).getTags();
+			if (javaDocTags != null && javaDocTags.isEmpty() == false) {
+				printer.write(transfo.apply("")).writeln();
+				for (CtJavaDocTag docTag : javaDocTags) {
+					printJavaDocTag(printer, docTag, transfo);
+				}
+			}
+		}
+	}
+
+	static void printJavaDocTag(PrinterHelper printer, CtJavaDocTag docTag, Function<String, String> transfo) {
+		printer.write(transfo.apply(CtJavaDocTag.JAVADOC_TAG_PREFIX));
 		printer.write(docTag.getType().name().toLowerCase());
 		printer.write(" ");
 		if (docTag.getType().hasParam()) {
@@ -113,11 +127,8 @@ static void printJavaDocTag(PrinterHelper printer, CtJavaDocTag docTag) {
 		String[] tagLines = LINE_SEPARATORS_RE.split(docTag.getContent());
 		for (int i = 0; i < tagLines.length; i++) {
 			String com = tagLines[i];
-			if (i > 0 || docTag.getType().hasParam()) {
-				printer.write(DefaultJavaPrettyPrinter.COMMENT_STAR);
-			}
 			if (docTag.getType().hasParam()) {
-				printer.write("\t\t");
+				printer.write(transfo.apply("\t\t"));
 			}
 			printer.write(com.trim()).writeln();
 		}

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

@@ -980,7 +980,7 @@ public void visitCtJavaDocTag(CtJavaDocTag docTag) {
 		 * E.g. from CtJavaDocTag#toString
 		 * Write directly to PrinterHelper, because java doc tag is not a java token. Normally it is part of COMMENT token.
 		 */
-		CommentHelper.printJavaDocTag(printer.getPrinterHelper(), docTag);
+		CommentHelper.printJavaDocTag(printer.getPrinterHelper(), docTag, x -> { return x; });
 	}
 
 	@Override

src/main/java/spoon/support/reflect/declaration/CtElementImpl.java

@@ -21,8 +21,6 @@
 import spoon.reflect.ModelElementContainerDefaultCapacities;
 import spoon.reflect.annotations.MetamodelPropertyField;
 import spoon.reflect.code.CtComment;
-import spoon.reflect.code.CtJavaDoc;
-import spoon.reflect.code.CtJavaDocTag;
 import spoon.reflect.cu.CompilationUnit;
 import spoon.reflect.cu.SourcePosition;
 import spoon.reflect.declaration.CtAnnotation;
@@ -75,6 +73,8 @@
 import java.util.Map;
 import java.util.Set;
 
+import static spoon.reflect.visitor.CommentHelper.printComment;
+
 /**
  * Contains the default implementation of most CtElement methods.
  *
@@ -186,12 +186,7 @@ public List<CtAnnotation<? extends Annotation>> getAnnotations() {
 	public String getDocComment() {
 		for (CtComment ctComment : comments) {
 			if (ctComment.getCommentType() == CtComment.CommentType.JAVADOC) {
-				StringBuilder result = new StringBuilder();
-				result.append(ctComment.getContent() + System.lineSeparator());
-				for (CtJavaDocTag tag: ((CtJavaDoc) ctComment).getTags()) {
-					result.append(tag.toString()); // the tag already contains a new line
-				}
-				return result.toString();
+				return printComment(ctComment);
 			}
 		}
 		return "";

src/test/java/spoon/test/javadoc/JavaDocTest.java

@@ -68,7 +68,7 @@ public void testJavaDocReprint() {
 
 		// contract: getDocComment returns the comment content together with the tag content
 		CtMethod<?> method = aClass.getMethodsByName("create").get(0);
-		assertEquals("Creates an annotation type." + System.lineSeparator()
+		assertEquals("Creates an annotation type." + System.lineSeparator() + System.lineSeparator()
 				+ "@param owner" + System.lineSeparator()
 				+ "\t\tthe package of the annotation type" + System.lineSeparator()
 				+ "@param simpleName" + System.lineSeparator()