Allow to indent and align with tabs instead of spaces

javaparser-core-testing/src/test/java/com/github/javaparser/printer/PrettyPrinterTest.java

@@ -29,7 +29,10 @@
 import com.github.javaparser.ast.type.PrimitiveType;
 import org.junit.Test;
 
-import static com.github.javaparser.JavaParser.*;
+import static com.github.javaparser.JavaParser.parse;
+import static com.github.javaparser.JavaParser.parseBodyDeclaration;
+import static com.github.javaparser.printer.PrettyPrinterConfiguration.IndentType.TABS;
+import static com.github.javaparser.printer.PrettyPrinterConfiguration.IndentType.TABS_WITH_SPACE_ALIGN;
 import static com.github.javaparser.utils.TestUtils.assertEqualsNoEol;
 import static org.junit.Assert.assertEquals;
 
@@ -222,4 +225,56 @@ public void prettyAlignMethodCallChainsIndentsArgumentsWithBlocksCorrectly() {
                 "    }\n" +
                 "}\n", printed);
     }
+
+    @Test
+    public void indentWithTabsAsFarAsPossible() {
+
+        CompilationUnit cu = JavaParser.parse("class Foo { void bar() { foo().bar().baz(() -> { boo().baa().bees(a, b, c); }).bam(); } }");
+        String printed = new PrettyPrinter(new PrettyPrinterConfiguration()
+                .setColumnAlignFirstMethodChain(true)
+                .setColumnAlignParameters(true)
+                .setIndentType(TABS)
+                .setIndentSize(1))
+                .print(cu);
+
+        assertEqualsNoEol("class Foo {\n" +
+                "\n" +
+                "\tvoid bar() {\n" +
+                "\t\tfoo().bar()\n" +
+                "\t\t\t .baz(() -> {\n" +
+                "\t\t\t\t\t  boo().baa()\n" +
+                "\t\t\t\t\t\t   .bees(a,\n" +
+                "\t\t\t\t\t\t\t\t b,\n" +
+                "\t\t\t\t\t\t\t\t c);\n" +
+                "\t\t\t\t  })\n" +
+                "\t\t\t .bam();\n" +
+                "\t}\n" +
+                "}\n", printed);
+    }
+
+    @Test
+    public void indentWithTabsAlignWithSpaces() {
+
+        CompilationUnit cu = JavaParser.parse("class Foo { void bar() { foo().bar().baz(() -> { boo().baa().bee(a, b, c); }).bam(); } }");
+        String printed = new PrettyPrinter(new PrettyPrinterConfiguration()
+                .setColumnAlignFirstMethodChain(true)
+                .setColumnAlignParameters(true)
+                .setIndentType(TABS_WITH_SPACE_ALIGN)
+                .setIndentSize(1))
+                .print(cu);
+
+        assertEqualsNoEol("class Foo {\n" +
+                "\n" +
+                "\tvoid bar() {\n" +
+                "\t\tfoo().bar()\n" +
+                "\t\t     .baz(() -> {\n" +
+                "\t\t          \tboo().baa()\n" +
+                "\t\t          \t     .bee(a,\n" +
+                "\t\t          \t          b,\n" +
+                "\t\t          \t          c);\n" +
+                "\t\t          })\n" +
+                "\t\t     .bam();\n" +
+                "\t}\n" +
+                "}\n", printed);
+    }
 }

javaparser-core/src/main/java/com/github/javaparser/printer/ConcreteSyntaxModel.java

@@ -42,7 +42,6 @@
 import static com.github.javaparser.ast.observer.ObservableProperty.*;
 import static com.github.javaparser.printer.concretesyntaxmodel.CsmConditional.Condition.*;
 import static com.github.javaparser.printer.concretesyntaxmodel.CsmElement.*;
-import static com.github.javaparser.utils.Utils.EOL;
 
 /**
  * The Concrete Syntax Model for a single node type. It knows the syntax used to represent a certain element in Java
@@ -934,7 +933,7 @@ public static void genericPrettyPrint(Node node, SourcePrinter printer) {
     }
 
     public static String genericPrettyPrint(Node node) {
-        SourcePrinter sourcePrinter = new SourcePrinter("    ", EOL);
+        SourcePrinter sourcePrinter = new SourcePrinter();
         forClass(node.getClass()).prettyPrint(node, sourcePrinter);
         return sourcePrinter.getSource();
     }

javaparser-core/src/main/java/com/github/javaparser/printer/PrettyPrintVisitor.java

@@ -56,7 +56,7 @@ public class PrettyPrintVisitor implements VoidVisitor<Void> {
 
     public PrettyPrintVisitor(PrettyPrinterConfiguration prettyPrinterConfiguration) {
         configuration = prettyPrinterConfiguration;
-        printer = new SourcePrinter(configuration.getIndent(), configuration.getEndOfLineCharacter());
+        printer = new SourcePrinter(configuration);
     }
 
     public String getSource() {
@@ -133,7 +133,7 @@ private void printTypeParameters(final NodeList<TypeParameter> args, final Void
     private void printArguments(final NodeList<Expression> args, final Void arg) {
         printer.print("(");
         if (configuration.isColumnAlignParameters()) {
-            printer.indentTo(printer.getCursor().column);
+            printer.indentWithAlignTo(printer.getCursor().column);
         }
         if (!isNullOrEmpty(args)) {
             for (final Iterator<Expression> i = args.iterator(); i.hasNext(); ) {
@@ -721,8 +721,7 @@ public void visit(final MethodCallExpr n, final Void arg) {
             scope.accept(this, arg);
             if (configuration.isColumnAlignFirstMethodChain()) {
                 if (!(scope instanceof MethodCallExpr) || !((MethodCallExpr) scope).getScope().isPresent()) {
-                    printer.unindent();
-                    printer.indentToCursor();
+                    printer.reindentWithAlignToCursor();
                 } else {
                     printer.println();
                 }

javaparser-core/src/main/java/com/github/javaparser/printer/PrettyPrinterConfiguration.java

@@ -25,20 +25,62 @@
 
 import java.util.function.Function;
 
+import static com.github.javaparser.printer.PrettyPrinterConfiguration.IndentType.SPACES;
+import static com.github.javaparser.printer.PrettyPrinterConfiguration.IndentType.TABS;
 import static com.github.javaparser.utils.Utils.EOL;
+import static com.github.javaparser.utils.Utils.assertNonNegative;
 import static com.github.javaparser.utils.Utils.assertNotNull;
+import static com.github.javaparser.utils.Utils.assertPositive;
 
 /**
  * Configuration options for the {@link PrettyPrinter}.
  */
 public class PrettyPrinterConfiguration {
+    public enum IndentType {
+        /**
+         * Indent with spaces.
+         */
+        SPACES,
+
+        /**
+         * Indent with tabs as far as possible.
+         * For proper aligning, the tab width is necessary and by default 4.
+         */
+        TABS,
+
+        /**
+         * Indent with tabs but align with spaces when wrapping and aligning
+         * method call chains and method call parameters.
+         *
+         * <p/><i>Example result:</i>
+         * <pre>
+         * class Foo {
+         *
+         * \tvoid bar() {
+         * \t\tfoo().bar()
+         * \t\t......baz(() -> {
+         * \t\t..........\tboo().baa()
+         * \t\t..........\t......bee(a,
+         * \t\t..........\t..........b,
+         * \t\t..........\t..........c);
+         * \t\t..........})
+         * \t\t......bam();
+         * \t}
+         * }
+         * </pre>
+         */
+        TABS_WITH_SPACE_ALIGN
+    }
+
     public static final int DEFAULT_MAX_ENUM_CONSTANTS_TO_ALIGN_HORIZONTALLY = 5;
 
     private boolean orderImports = false;
     private boolean printComments = true;
     private boolean printJavadoc = true;
     private boolean columnAlignParameters = false;
     private boolean columnAlignFirstMethodChain = false;
+    private IndentType indentType = SPACES;
+    private int tabWidth = 4;
     private int indentSize = 4;
     private String endOfLineCharacter = EOL;
     private Function<PrettyPrinterConfiguration, PrettyPrintVisitor> visitorFactory = PrettyPrintVisitor::new;
@@ -47,12 +89,20 @@ public class PrettyPrinterConfiguration {
     /**
      * Set the string to use for indenting. For example: "\t", "    ", "".
      *
-     * @deprecated use setIndentSize. Tabs are no longer supported.
+     * @deprecated use {@link #setIndentSize(int)} and {@link #setIndentType(IndentType)}.
      */
     @Deprecated
     public PrettyPrinterConfiguration setIndent(String indent) {
         System.err.println("PrettyPrinterConfiguration.setIndent is deprecated, please review the changes.");
-        indentSize = indent.length();
+        if (indent.matches(" *")) {
+            indentSize = indent.length();
+            indentType = SPACES;
+        } else if (indent.matches("\\t+")) {
+            indentSize = indent.length();
+            indentType = TABS;
+        } else {
+            throw new NotImplementedException();
+        }
         return this;
     }
 
@@ -61,8 +111,22 @@ public PrettyPrinterConfiguration setIndent(String indent) {
      */
     public String getIndent() {
         StringBuilder indentString = new StringBuilder();
+        char indentChar;
+        switch (indentType) {
+            case SPACES:
+                indentChar = ' ';
+                break;
+
+            case TABS:
+            case TABS_WITH_SPACE_ALIGN:
+                indentChar = '\t';
+                break;
+
+            default:
+                throw new AssertionError("Unhandled indent type");
+        }
         for (int i = 0; i < indentSize; i++) {
-            indentString.append(' ');
+            indentString.append(indentChar);
         }
         return indentString.toString();
     }
@@ -72,13 +136,40 @@ public int getIndentSize() {
     }
 
     /**
-     * Set the size of the indent in spaces.
+     * Set the size of the indent in characters.
      */
-    public PrettyPrinterConfiguration setIndentSize(int size) {
-        if (size < 0) {
-            throw new IllegalArgumentException("Indent must be >= 0");
-        }
-        this.indentSize = size;
+    public PrettyPrinterConfiguration setIndentSize(int indentSize) {
+        this.indentSize = assertNonNegative(indentSize);
+        return this;
+    }
+
+    /**
+     * Get the type of indent to produce.
+     */
+    public IndentType getIndentType() {
+        return indentType;
+    }
+
+    /**
+     * Set the type of indent to produce.
+     */
+    public PrettyPrinterConfiguration setIndentType(IndentType indentType) {
+        this.indentType = assertNotNull(indentType);
+        return this;
+    }
+
+    /**
+     * Get the tab width for pretty aligning.
+     */
+    public int getTabWidth() {
+        return tabWidth;
+    }
+
+    /**
+     * Set the tab width for pretty aligning.
+     */
+    public PrettyPrinterConfiguration setTabWidth(int tabWidth) {
+        this.tabWidth = assertPositive(tabWidth);
         return this;
     }