Issue checkstyle#6308: made IndentLevel immutable

rnveach · Dec 22, 2018 · fd560ad · fd560ad
1 parent 4974cf9
commit fd560ad
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Showing 6 changed files with 44 additions and 28 deletions.
diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/ArrayInitHandler.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/ArrayInitHandler.java
@@ -70,8 +70,8 @@ protected DetailAST getLeftCurly() {
     @Override
     protected IndentLevel curlyIndent() {
         final IndentLevel level = new IndentLevel(getIndent(), getBraceAdjustment());
-        level.addAcceptedIndent(level.getLastIndentLevel() + getLineWrappingIndentation());
-        return level;
+        return IndentLevel.addAcceptable(level, level.getLastIndentLevel()
+                + getLineWrappingIndentation());
     }
 
     @Override
@@ -91,7 +91,7 @@ protected DetailAST getListChild() {
 
     @Override
     protected IndentLevel getChildrenExpectedIndent() {
-        final IndentLevel expectedIndent =
+        IndentLevel expectedIndent =
             new IndentLevel(getIndent(), getIndentCheck().getArrayInitIndent(),
                     getIndentCheck().getLineWrappingIndentation());
 
@@ -100,8 +100,8 @@ protected IndentLevel getChildrenExpectedIndent() {
         final int firstChildPos =
             getNextFirstNonBlankOnLineAfter(firstLine, lcurlyPos);
         if (firstChildPos >= 0) {
-            expectedIndent.addAcceptedIndent(firstChildPos);
-            expectedIndent.addAcceptedIndent(lcurlyPos + getLineWrappingIndentation());
+            expectedIndent = IndentLevel.addAcceptable(expectedIndent, firstChildPos, lcurlyPos
+                    + getLineWrappingIndentation());
         }
         return expectedIndent;
     }

diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/BlockParentHandler.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/BlockParentHandler.java
@@ -264,8 +264,8 @@ protected IndentLevel getChildrenExpectedIndent() {
             }
             else if (isOnStartOfLine(getRightCurly())) {
                 final IndentLevel level = new IndentLevel(curlyIndent(), getBasicOffset());
-                level.addAcceptedIndent(level.getFirstIndentLevel() + getLineWrappingIndent());
-                indentLevel = level;
+                indentLevel = IndentLevel.addAcceptable(level, level.getFirstIndentLevel()
+                        + getLineWrappingIndent());
             }
         }
         return indentLevel;

diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/IndentLevel.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/IndentLevel.java
@@ -24,13 +24,20 @@
 /**
  * Encapsulates representation of notion of expected indentation levels.
  * Provide a way to have multiple acceptable levels.
- *
+ * This class is immutable.
  */
 public class IndentLevel {
 
     /** Set of acceptable indentation levels. */
     private final BitSet levels = new BitSet();
 
+    /**
+     * Creates new instance with no acceptable indentation level.
+     * This is only used internally to combine multiple levels.
+     */
+    private IndentLevel() {
+    }
+
     /**
      * Creates new instance with one acceptable indentation level.
      * @param indent acceptable indentation level.
@@ -83,19 +90,29 @@ public boolean isGreaterThan(int indent) {
     }
 
     /**
-     * Adds one more acceptable indentation level.
-     * @param indent new acceptable indentation.
+     * Adds one or more acceptable indentation level.
+     * @param base class to add new indentations to.
+     * @param additions new acceptable indentation.
      */
-    public void addAcceptedIndent(int indent) {
-        levels.set(indent);
+    public static IndentLevel addAcceptable(IndentLevel base, int... additions) {
+        final IndentLevel result = new IndentLevel();
+        result.levels.or(base.levels);
+        for (int addition : additions) {
+            result.levels.set(addition);
+        }
+        return result;
     }
 
     /**
-     * Adds one more acceptable indentation level.
-     * @param indent new acceptable indentation.
+     * Combines 2 acceptable indentation level classes.
+     * @param base class to add new indentations to.
+     * @param addition new acceptable indentation.
      */
-    public void addAcceptedIndent(IndentLevel indent) {
-        levels.or(indent.levels);
+    public static IndentLevel addAcceptable(IndentLevel base, IndentLevel addition) {
+        final IndentLevel result = new IndentLevel();
+        result.levels.or(base.levels);
+        result.levels.or(addition.levels);
+        return result;
     }
 
     /**

diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/LabelHandler.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/LabelHandler.java
@@ -51,8 +51,7 @@ public LabelHandler(IndentationCheck indentCheck,
     @Override
     protected IndentLevel getIndentImpl() {
         final IndentLevel level = new IndentLevel(super.getIndentImpl(), -getBasicOffset());
-        level.addAcceptedIndent(super.getIndentImpl());
-        return level;
+        return IndentLevel.addAcceptable(level, super.getIndentImpl());
     }
 
     /**

diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/MethodCallHandler.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/MethodCallHandler.java
@@ -166,22 +166,22 @@ public IndentLevel getSuggestedChildIndent(AbstractExpressionHandler child) {
         // will not have the right line num, so just get the child name
 
         final DetailAST ident = getMethodIdentAst();
+        final DetailAST rparen = getMainAst().findFirstToken(TokenTypes.RPAREN);
         IndentLevel suggestedLevel = new IndentLevel(getLineStart(ident));
-        if (!areOnSameLine(child.getMainAst().getFirstChild(), ident)) {
-            suggestedLevel = new IndentLevel(suggestedLevel,
-                    getBasicOffset(),
-                    getIndentCheck().getLineWrappingIndentation());
-        }
 
         // If the right parenthesis is at the start of a line;
         // include line wrapping in suggested indent level.
-        final DetailAST rparen = getMainAst().findFirstToken(TokenTypes.RPAREN);
         if (getLineStart(rparen) == rparen.getColumnNo()) {
-            suggestedLevel.addAcceptedIndent(new IndentLevel(
+            suggestedLevel = IndentLevel.addAcceptable(suggestedLevel, new IndentLevel(
                     getParent().getSuggestedChildIndent(this),
                     getIndentCheck().getLineWrappingIndentation()
             ));
         }
+        else if (!areOnSameLine(child.getMainAst().getFirstChild(), ident)) {
+            suggestedLevel = new IndentLevel(suggestedLevel,
+                    getBasicOffset(),
+                    getIndentCheck().getLineWrappingIndentation());
+        }
 
         return suggestedLevel;
     }

diff --git a/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/ObjectBlockHandler.java b/src/main/java/com/puppycrawl/tools/checkstyle/checks/indentation/ObjectBlockHandler.java
@@ -66,7 +66,7 @@ protected IndentLevel getIndentImpl() {
         final DetailAST parentAST = getMainAst().getParent();
         IndentLevel indent = getParent().getIndent();
         if (parentAST.getType() == TokenTypes.LITERAL_NEW) {
-            indent.addAcceptedIndent(super.getIndentImpl());
+            indent = IndentLevel.addAcceptable(indent, super.getIndentImpl());
         }
         else if (parentAST.getType() == TokenTypes.ENUM_CONSTANT_DEF) {
             indent = super.getIndentImpl();
@@ -89,8 +89,8 @@ public void checkIndentation() {
     @Override
     protected IndentLevel curlyIndent() {
         final IndentLevel indent = super.curlyIndent();
-        indent.addAcceptedIndent(indent.getFirstIndentLevel() + getLineWrappingIndentation());
-        return indent;
+        return IndentLevel.addAcceptable(indent, indent.getFirstIndentLevel()
+                + getLineWrappingIndentation());
     }
 
     /**