platform/lang-impl/src/com/intellij/indentation/IndentationAnnotatorVisitor.java

   1 package com.intellij.indentation;
   2
   3 import com.intellij.lang.annotation.AnnotationHolder;
   4 import com.intellij.psi.PsiElement;
   5 import com.intellij.psi.PsiElementVisitor;
   6 import com.intellij.psi.PsiFile;
   7 import com.intellij.psi.tree.IElementType;
   8 import com.intellij.psi.util.PsiTreeUtil;
   9 import org.jetbrains.annotations.NotNull;
  10
  11 /**
  12  * @author oleg
  13  */
  14 public class IndentationAnnotatorVisitor extends PsiElementVisitor {
  15   protected final AnnotationHolder myHolder;
  16   private final IElementType myIndentTokenType;
  17   private final IElementType myEolTokenType;
  18
  19   public IndentationAnnotatorVisitor(@NotNull final AnnotationHolder holder,
  20                                      final IElementType indentTokenType,
  21                                      final IElementType eolTokenType) {
  22     myHolder = holder;
  23     myIndentTokenType = indentTokenType;
  24     myEolTokenType = eolTokenType;
  25   }
  26
  27   @SuppressWarnings({"ConstantConditions"})
  28   @Override
  29   public void visitFile(final PsiFile file) {
  30     int lastIndent = 0;
  31     IndentInfo indentInfo = null;
  32     PsiElement leaf = PsiTreeUtil.getDeepestFirst(file);
  33     if (leaf == null || leaf instanceof PsiFile){
  34       return;
  35     }
  36     PsiElement nextLeaf = PsiTreeUtil.nextLeaf(leaf);
  37
  38     // First leaf check
  39     if (leaf.getNode().getElementType() == myIndentTokenType){
  40       myHolder.createErrorAnnotation(leaf, "Indenting at the beginning of the document is illegal");
  41     }
  42     leaf = nextLeaf;
  43     nextLeaf = leaf != null ? PsiTreeUtil.nextLeaf(leaf) : null;
  44
  45     // Iterating over leafs
  46     while (leaf != null) {
  47       final IElementType leafType = leaf.getNode().getElementType();
  48       if (leafType == myIndentTokenType && nextLeaf!=null && nextLeaf.getNode().getElementType() != myEolTokenType){
  49         final String currentIndentText = leaf.getText();
  50         final IndentInfo currentIndent = getIndent(currentIndentText);
  51         final int currentIndentLength = currentIndent.length;
  52         // Check if spaces and tabs are mixed
  53         if (currentIndentLength == -1){
  54           myHolder.createErrorAnnotation(leaf, "Indentation can't use both tabs and spaces");
  55         }
  56         else
  57         if (currentIndentLength > 0) {
  58           // If we don't have indent info registered
  59           if (indentInfo == null){
  60             indentInfo = currentIndent;
  61             lastIndent = currentIndentLength;
  62           } else {
  63             final Boolean useTab = indentInfo.useTab;
  64             final int indentInfoLength = indentInfo.length;
  65             // If indent and current indent use different space and tabs
  66             if (useTab && currentIndentText.contains(" ") || !useTab && currentIndentText.contains("\t")) {
  67               final String message = useTab
  68                                      ? "Inconsistent indentation: " + currentIndentLength +
  69                                        " spaces were used for indentation, but the rest of the document was indented using " +
  70                                        indentInfoLength + " tabs"
  71                                      : "Inconsistent indentation: " + currentIndentLength +
  72                                        " tabs were used for indentation, but the rest of the document was indented using " +
  73                                        indentInfoLength + " spaces";
  74               myHolder.createErrorAnnotation(leaf, message);
  75             } else {
  76               // Check indent length
  77               final int delta = currentIndentLength - lastIndent;
  78               if (currentIndentLength % indentInfoLength != 0 || delta > indentInfoLength) {
  79                 final String message = useTab
  80                                        ? currentIndentLength + " tabs were used for indentation. Must be indented using " + indentInfoLength + " tabs"
  81                                        : currentIndentLength + " spaces were used for indentation. Must be indented using " + indentInfoLength + " spaces";
  82                 myHolder.createErrorAnnotation(leaf, message);
  83               }
  84               lastIndent = currentIndentLength / indentInfoLength * indentInfoLength;
  85             }
  86           }
  87         }
  88       }
  89       leaf = nextLeaf;
  90       nextLeaf = leaf != null ? PsiTreeUtil.nextLeaf(leaf) : null;
  91     }
  92   }
  93
  94
  95   private class IndentInfo {
  96     final int length;
  97     final boolean useTab;
  98
  99     private IndentInfo(final int length, final boolean useTab) {
 100       this.length = length;
 101       this.useTab = useTab;
 102     }
 103   }
 104
 105
 106   private IndentInfo getIndent(final String text) {
 107     if (text.length() == 0){
 108       return new IndentInfo(0, false);
 109     }
 110     if (text.contains("\t ") || text.contains(" \t")){
 111       return new IndentInfo(-1, false);
 112     }
 113     return new IndentInfo(text.length(), text.contains("\t"));
 114   }
 115 }