org.eclipse.xtext.parsetree.reconstr.impl.NodeIterator Java Examples

protected List<ILeafNode> findNextHiddenLeafs(final INode node) {
  ArrayList<ILeafNode> _xblockexpression = null;
  {
    final ArrayList<ILeafNode> result = CollectionLiterals.<ILeafNode>newArrayList();
    final NodeIterator ni = new NodeIterator(node);
    while (ni.hasNext()) {
      {
        final INode next = ni.next();
        if ((next instanceof ILeafNode)) {
          boolean _isHidden = ((ILeafNode)next).isHidden();
          if (_isHidden) {
            result.add(((ILeafNode)next));
          } else {
            return result;
          }
        }
      }
    }
    _xblockexpression = result;
  }
  return _xblockexpression;
}
 

/**
 * Returns the list of nodes that belong to 'root' node and follow the 'from' node.
 *
 * @param from
 *          node model element to start from, must not be {@code null}
 * @param root
 *          top-level node model element, must not be {@code null}
 * @return list of hiddens nodes, possibly empty, but never {@code null}
 */
private List<INode> getRemainingHiddenNodesInContainer(final INode from, final INode root) {
  if (from == null || root == null) {
    return Collections.emptyList();
  }
  List<INode> out = Lists.newArrayList();
  NodeIterator nodes = new NodeIterator(from);
  while (nodes.hasNext()) {
    INode next = nodes.next();
    if (next.getStartLine() > root.getEndLine()) {
      return out;
    } else if (tokenUtil.isWhitespaceOrCommentNode(next)) {
      out.add(next);
    } else if (tokenUtil.isToken(next)) {
      return out;
    }
  }
  return out;
}
 

/**
 * Returns trailing comments of the given leaf node.
 *
 * @param node
 *          leaf element of the node model to start looking from, must not be {@code null}
 * @return list of hidden tokens, can be empty, never {@code null}
 */
private List<INode> getTrailingCommentsIncludingWhitespace(final ILeafNode node) {
  List<INode> associatedNodes = Lists.newLinkedList();
  Set<INode> pendingWhitespace = Sets.newHashSet();
  INode lastLink = node;
  NodeIterator nodes = new NodeIterator(lastLink);
  while (nodes.hasNext()) {
    INode next = nodes.next();
    if (tokenUtil.isCommentNode(next)) {
      if (isTrailingCommentFor(next, lastLink)) {
        lastLink = next;
        associatedNodes.addAll(pendingWhitespace);
        pendingWhitespace.clear();
        associatedNodes.add(next);
      } else {
        break;
      }
    } else if (tokenUtil.isWhitespaceNode(next)) {
      pendingWhitespace.add(next);
    } else if (next instanceof ILeafNode) {
      break;
    }
  }
  return associatedNodes;
}
 

/**
 * Helper method that collects all the preceding hidden tokens for the given node.
 *
 * @param to
 *          node model element to get the tokens for, must not be {@code null}
 * @param deletedSemanticElements
 *          set of semantic elements that have been deleted from the model, must not be {@code null}
 * @return list of hidden tokens, never {@code null}, can be empty
 */
private List<INode> getPrecedingHiddenTokens(final INode to, final Set<EObject> deletedSemanticElements) {
  List<INode> result = Lists.newLinkedList();
  NodeIterator nodes = new NodeIterator(to);
  while (nodes.hasPrevious()) {
    INode previous = nodes.previous();
    if (previous.getTotalEndOffset() < rootOffset || previous.equals(lastEmittedNode)) {
      break;
    } else if (tokenUtil.isWhitespaceOrCommentNode(previous)) {
      if (!emittedComments.contains(previous)) {
        result.add(0, previous);
      }
    } else if (belongsToDeletedElement(previous)) {
      handleDeletedElement(result, deletedSemanticElements, previous);
      nodes.prune();
    } else {
      break;
    }
  }
  return result;
}
 

/**
 * Helper method that collects all the hidden tokens that follow the given node.
 *
 * @param from
 *          starting point in the node model, must not be {@code null}
 * @param deletedSemanticElements
 *          set of semantic elements that have been deleted from the model, must not be {@code null}
 * @return list of hidden tokens, never {@code null}, can be empty
 */
private List<INode> getFollowingHiddenTokens(final INode from, final Set<EObject> deletedSemanticElements) {
  List<INode> result = Lists.newArrayList();
  NodeIterator nodes = new NodeIterator(from);
  while (nodes.hasNext()) {
    INode next = nodes.next();
    if (next.getTotalOffset() > rootEndOffset || next.equals(lastEmittedNode)) {
      break;
    } else if (tokenUtil.isWhitespaceOrCommentNode(next)) {
      if (!emittedComments.contains(next)) {
        result.add(next);
      }
    } else if (belongsToDeletedElement(next)) {
      handleDeletedElement(result, deletedSemanticElements, next);
      nodes.prune();
    } else {
      break;
    }
  }
  return result;
}
 

public EmitterNodeIterator(INode fromNode, INode toNode, boolean passAbsorber, boolean allowHidden) {
	if (fromNode != null) {
		this.iterator = new NodeIterator(fromNode);
		this.passAbsorber = passAbsorber;
		if (toNode != null) {
			if (toNode == fromNode)
				this.end = toNode.getOffset() + toNode.getLength();
			else if (toNode.getOffset() < fromNode.getOffset())
				this.end = toNode.getOffset() + toNode.getLength();
			else
				this.end = toNode.getOffset();
		} else
			this.end = Integer.MAX_VALUE;
		this.allowHidden = allowHidden;
		next();
	}
}
 

protected List<INode> getRemainingHiddenNodesInContainer(INode from, INode root) {
	if (from == null || root == null)
		return Collections.emptyList();
	List<INode> out = Lists.newArrayList();
	NodeIterator ni = new NodeIterator(from);
	while (ni.hasNext()) {
		INode next = ni.next();
		if (next.getTotalOffset() > root.getTotalEndOffset())
			return out;
		else if (tokenUtil.isWhitespaceOrCommentNode(next)) {
			out.add(next);
		} else if (tokenUtil.isToken(next))
			return Collections.emptyList();
	}
	return out;
}
 

protected Set<INode> getTrailingCommentsIncludingWhitespace(ILeafNode node) {
	Set<INode> associatedNodes = Sets.newHashSet();
	Set<INode> pendingWhitespace = Sets.newHashSet();
	INode lastLink = node;
	NodeIterator ni = new NodeIterator(lastLink);
	while(ni.hasNext()) {
		INode next = ni.next();
		if (tokenUtil.isCommentNode(next)) {
			if (isTrailingCommentFor(next, lastLink)) {
				lastLink = next;
				associatedNodes.addAll(pendingWhitespace);
				associatedNodes.add(next);
			} else {
				break;
			}
		} else if (tokenUtil.isWhitespaceNode(next)) {
			pendingWhitespace.add(next);
		} else if (next instanceof ILeafNode){
			break;
		}
	}
	return associatedNodes;
}
 

protected Set<INode> getLeadingCommentsIncludingWhitespace(ILeafNode node) {
	Set<INode> associatedNodes = Sets.newHashSet();
	Set<INode> pendingWhitespace = Sets.newHashSet();
	INode lastLink = node;
	NodeIterator ni = new NodeIterator(lastLink);
	while(ni.hasPrevious()) {
		INode prev = ni.previous();
		if (tokenUtil.isCommentNode(prev)) {
			if (isLeadingCommentFor(prev, lastLink)) {
				lastLink = prev;
				associatedNodes.addAll(pendingWhitespace);
				associatedNodes.add(prev);
			} else {
				break;
			}
		} else if (tokenUtil.isWhitespaceNode(prev)) {
			pendingWhitespace.add(prev);
		} else if (prev instanceof ILeafNode){
			break;
		}
	}
	return associatedNodes;
}
 

protected ILeafNode findPreviousLeaf(final INode node, final Function1<? super ILeafNode, ? extends Boolean> matches) {
  INode current = node;
  while ((current instanceof ICompositeNode)) {
    current = ((ICompositeNode)current).getLastChild();
  }
  if (((current instanceof ILeafNode) && (matches.apply(((ILeafNode) current))).booleanValue())) {
    return ((ILeafNode) current);
  }
  if ((current != null)) {
    final NodeIterator ni = new NodeIterator(current);
    while (ni.hasPrevious()) {
      {
        final INode previous = ni.previous();
        if (((previous instanceof ILeafNode) && (matches.apply(((ILeafNode) previous))).booleanValue())) {
          return ((ILeafNode) previous);
        }
      }
    }
  }
  return null;
}
 

@Test public void testPruneComposite() throws Exception {
	NodeIterator nodeIterator = new NodeIterator(nodes[3]);
	nodeIterator.prune();
	assertEquals(nodes[6], nodeIterator.next());
	assertEquals(nodes[3], nodeIterator.previous());
	assertEquals(nodes[2], nodeIterator.previous());
	assertEquals(nodes[1], nodeIterator.previous());
}
 

@Test public void testPruneLeaf() throws Exception {
	// pruning a leaf should not have any effect
	NodeIterator nodeIterator = new NodeIterator(nodes[8]);
	nodeIterator.prune();
	assertEquals(nodes[9], nodeIterator.next());
	assertEquals(nodes[8], nodeIterator.previous());
	assertEquals(nodes[7], nodeIterator.previous());
	assertEquals(nodes[6], nodeIterator.previous());
}
 

protected void checkAscending(int index) {
	int i = index;
	NodeIterator nodeIterator = new NodeIterator(nodes[i]);
	while (nodeIterator.hasNext()) {
		assertEquals("Ascending " + i, nodes[++i], nodeIterator.next());
	}
}
 

protected void checkDescending(int index) {
	int i = index;
	NodeIterator nodeIterator = new NodeIterator(nodes[i]);
	while (nodeIterator.hasPrevious()) {
		assertEquals(nodes[--i], nodeIterator.previous());
	}
}
 

protected List<ILeafNode> findPreviousHiddenLeafs(final INode node) {
  List<ILeafNode> _xblockexpression = null;
  {
    INode current = node;
    while ((current instanceof ICompositeNode)) {
      current = ((ICompositeNode)current).getLastChild();
    }
    final ArrayList<ILeafNode> result = CollectionLiterals.<ILeafNode>newArrayList();
    if ((current != null)) {
      final NodeIterator ni = new NodeIterator(current);
      while (ni.hasPrevious()) {
        {
          final INode previous = ni.previous();
          if (((!Objects.equal(previous, current)) && (previous instanceof ILeafNode))) {
            boolean _isHidden = ((ILeafNode) previous).isHidden();
            if (_isHidden) {
              result.add(((ILeafNode) previous));
            } else {
              return ListExtensions.<ILeafNode>reverse(result);
            }
          }
        }
      }
    }
    _xblockexpression = ListExtensions.<ILeafNode>reverse(result);
  }
  return _xblockexpression;
}
 

/**
 * Collects & emits the set of comments/whitespaces that logically belong to a container of some objects and <b>not</b> to the first child of the container.
 *
 * @param container
 *          node model element that represents a container, must not be {@code null}
 */
private void emitContainerComments(final INode container) {
  List<INode> containerComments = Lists.newArrayList();
  Set<INode> firstElementComments = getHiddenNodesBelongingTo(NodeModelUtils.findActualSemanticObjectFor(container));
  NodeIterator nodes = new NodeIterator(container);
  while (nodes.hasNext()) {
    INode next = nodes.next();
    if (firstElementComments.contains(next) || tokenUtil.isToken(next)) {
      break;
    } else if (tokenUtil.isWhitespaceOrCommentNode(next)) {
      containerComments.add(next);
    }
  }
  emitHiddenTokens(containerComments);
}
 

/**
 * Returns the leading comments of the given leaf node.
 *
 * @param node
 *          leaf element of the node model to look up to, must not be {@code null}
 * @return list of hidden tokens, can be empty, never {@code null}
 */
private List<INode> getLeadingCommentsIncludingWhitespace(final ILeafNode node) {
  List<INode> associatedNodes = Lists.newLinkedList();
  Set<INode> pendingWhitespace = Sets.newHashSet();
  INode lastLink = node;
  NodeIterator nodes = new NodeIterator(lastLink);
  while (nodes.hasPrevious()) {
    INode prev = nodes.previous();
    if (tokenUtil.isCommentNode(prev)) {
      if (isLeadingCommentFor(prev, lastLink)) {
        lastLink = prev;
        associatedNodes.addAll(0, pendingWhitespace);
        pendingWhitespace.clear();
        associatedNodes.add(0, prev);
      } else {
        break;
      }
    } else if (tokenUtil.isWhitespaceNode(prev)) {
      pendingWhitespace.add(prev);
    } else if (prev instanceof ILeafNode) {
      break;
    }
  }
  associatedNodes.addAll(0, pendingWhitespace);
  // We want trailing comments to have precedence over leading comments
  // Therefore all the trailing comments of the previous node must be computed
  // and deleted from the results, as they have been already output in previous call of 'emitTrailingTokens' method
  EObject nodeObject = NodeModelUtils.findActualSemanticObjectFor(node);
  ICompositeNode actualNode = NodeModelUtils.findActualNodeFor(nodeObject);
  INode previousNode = actualNode.getPreviousSibling();
  if (previousNode instanceof ICompositeNode) {
    associatedNodes.removeAll(getTrailingCommentsIncludingWhitespace(previousNode));
  }

  // Following line is need to insert a new line after the leading comments if it is needed, but wasn't originally present
  // See also usage in 'emitHiddenTokens'
  associatedNodes.add(0, new LeadingCommentsMarkerNode());
  return associatedNodes;
}
 

public ILeafNode findNextLeaf(INode node, Function1<? super ILeafNode, ? extends Boolean> matches) {
	if (node != null) {
		if (node instanceof ILeafNode && matches.apply((ILeafNode) node)) {
			return (ILeafNode) node;
		}
		NodeIterator ni = new NodeIterator(node);
		while (ni.hasNext()) {
			INode next = ni.next();
			if (next instanceof ILeafNode && matches.apply((ILeafNode) next)) {
				return (ILeafNode) next;
			}
		}
	}
	return null;
}
 

/**
 * Collects all the hidden tokens between two given nodes of the node model.
 *
 * @param from
 *          node that serves as a start point, must not be {@code null}
 * @param to
 *          search end point, must not be {@code null}
 * @param deletedSemanticElements
 *          set of the deleted semantic elements, must not be {@code null}
 * @return list of hidden tokens, never {@code null}, but can be empty
 */
private List<INode> getHiddenTokensBetween(final INode from, final INode to, final Set<EObject> deletedSemanticElements) {
  EObject fromElement = NodeModelUtils.findActualSemanticObjectFor(from);
  if (from.equals(NodeModelUtils.getNode(fromElement))) {
    // If the starting node represents some container, emit the comments that belong to it
    // This is needed to correctly handle some edge cases like ImportList in AvqScript
    // Logic for distinguishing between container's comments and the ones of first element is expected to be implemented in 'isLeadingCommentFor'
    emitContainerComments(from);
  }
  List<INode> result = Lists.newArrayList();
  boolean handleReordering = from.getTotalOffset() > to.getTotalOffset();
  if (!handleReordering) {
    // Elements are not reordered
    // Just going through the interval and collecting comments, unless they have already been emitted
    NodeIterator nodes = new NodeIterator(from);
    while (nodes.hasNext()) {
      INode next = nodes.next();
      if (tokenUtil.isWhitespaceOrCommentNode(next)) {
        if (!emittedComments.contains(next)) {
          result.add(next);
        }
      } else if (next.equals(to)) {
        // We have hit the 'to' node
        // If it is a composite one, we have to iterate through its children
        // and collect whitespaces/comments until we encounter first token (keyword, identifier...)
        if (next instanceof ICompositeNode && (GrammarUtil.isDatatypeRuleCall(next.getGrammarElement())
            || GrammarUtil.isEnumRuleCall(next.getGrammarElement()) || next.getGrammarElement() instanceof CrossReference)) {
          while (nodes.hasNext()) {
            INode lastNodeChild = nodes.next();
            if (tokenUtil.isWhitespaceOrCommentNode(lastNodeChild)) {
              if (!emittedComments.contains(lastNodeChild)) {
                result.add(lastNodeChild);
              }
            } else if (lastNodeChild instanceof ILeafNode) {
              break;
            }
          }
          break;
        } else {
          // 'to' node is not a composite one, nothing to do here, just exit the loop
          break;
        }
      } else if (belongsToDeletedElement(next)) {
        handleDeletedElement(result, deletedSemanticElements, next);
        nodes.prune();
      } else if (tokenUtil.isToken(next)) {
        // We have encountered some token, but not the one we expected
        // Will be handled by invoking 'getLeadingCommentsIncludingWhitespace' method later
        handleReordering = true;
        break;
      }
    }
  }
  if (handleReordering) {
    return getLeadingCommentsIncludingWhitespace(to);
  }
  return result;
}