get_changed_ranges.h File Reference

#include "./tree_cursor.h"
#include "./subtree.h"

Go to the source code of this file.

Functions
typedef	Array (TSRange) TSRangeArray
void	ts_range_array_get_changed_ranges (const TSRange *old_ranges, unsigned old_range_count, const TSRange *new_ranges, unsigned new_range_count, TSRangeArray *differences)
bool	ts_range_array_intersects (const TSRangeArray *self, unsigned start_index, uint32_t start_byte, uint32_t end_byte)
unsigned	ts_subtree_get_changed_ranges (const Subtree *old_tree, const Subtree *new_tree, TreeCursor *cursor1, TreeCursor *cursor2, const TSLanguage *language, const TSRangeArray *included_range_differences, TSRange **ranges)

Function Documentation

Array()

typedef Array

(

TSRange

)

ts_range_array_get_changed_ranges()

void ts_range_array_get_changed_ranges	(	const TSRange *	old_ranges,
		unsigned	old_range_count,
		const TSRange *	new_ranges,
		unsigned	new_range_count,
		TSRangeArray *	differences
	)

Definition at line 46 of file get_changed_ranges.c.

  {
  unsigned new_index = 0;
  unsigned old_index = 0;
  Length current_position = length_zero();
  bool in_old_range = false;
  bool in_new_range = false;
 
  while (old_index < old_range_count || new_index < new_range_count) {
    const TSRange *old_range = &old_ranges[old_index];
    const TSRange *new_range = &new_ranges[new_index];
 
    Length next_old_position;
    if (in_old_range) {
      next_old_position = (Length) {old_range->end_byte, old_range->end_point};
    } else if (old_index < old_range_count) {
      next_old_position = (Length) {old_range->start_byte, old_range->start_point};
    } else {
      next_old_position = LENGTH_MAX;
    }
 
    Length next_new_position;
    if (in_new_range) {
      next_new_position = (Length) {new_range->end_byte, new_range->end_point};
    } else if (new_index < new_range_count) {
      next_new_position = (Length) {new_range->start_byte, new_range->start_point};
    } else {
      next_new_position = LENGTH_MAX;
    }
 
    if (next_old_position.bytes < next_new_position.bytes) {
      if (in_old_range != in_new_range) {
        ts_range_array_add(differences, current_position, next_old_position);
      }
      if (in_old_range) old_index++;
      current_position = next_old_position;
      in_old_range = !in_old_range;
    } else if (next_new_position.bytes < next_old_position.bytes) {
      if (in_old_range != in_new_range) {
        ts_range_array_add(differences, current_position, next_new_position);
      }
      if (in_new_range) new_index++;
      current_position = next_new_position;
      in_new_range = !in_new_range;
    } else {
      if (in_old_range != in_new_range) {
        ts_range_array_add(differences, current_position, next_new_position);
      }
      if (in_old_range) old_index++;
      if (in_new_range) new_index++;
      in_old_range = !in_old_range;
      in_new_range = !in_new_range;
      current_position = next_new_position;
    }
  }
}

References Length::bytes, TSRange::end_byte, TSRange::end_point, LENGTH_MAX, length_zero(), TSRange::start_byte, TSRange::start_point, and ts_range_array_add().

Referenced by ts_parser_parse(), and ts_tree_get_changed_ranges().

ts_range_array_intersects()

bool ts_range_array_intersects	(	const TSRangeArray *	self,
		unsigned	start_index,
		uint32_t	start_byte,
		uint32_t	end_byte
	)

Definition at line 30 of file get_changed_ranges.c.

  {
  for (unsigned i = start_index; i < self->size; i++) {
    TSRange *range = &self->contents[i];
    if (range->end_byte > start_byte) {
      if (range->start_byte >= end_byte) break;
      return true;
    }
  }
  return false;
}

References i, and capstone::range.

Referenced by ts_parser__has_included_range_difference(), and ts_subtree_get_changed_ranges().

ts_subtree_get_changed_ranges()

unsigned ts_subtree_get_changed_ranges	(	const Subtree *	old_tree,
		const Subtree *	new_tree,
		TreeCursor *	cursor1,
		TreeCursor *	cursor2,
		const TSLanguage *	language,
		const TSRangeArray *	included_range_differences,
		TSRange **	ranges
	)

Definition at line 357 of file get_changed_ranges.c.

  {
  TSRangeArray results = array_new();
 
  Iterator old_iter = iterator_new(cursor1, old_tree, language);
  Iterator new_iter = iterator_new(cursor2, new_tree, language);
 
  unsigned included_range_difference_index = 0;
 
  Length position = iterator_start_position(&old_iter);
  Length next_position = iterator_start_position(&new_iter);
  if (position.bytes < next_position.bytes) {
    ts_range_array_add(&results, position, next_position);
    position = next_position;
  } else if (position.bytes > next_position.bytes) {
    ts_range_array_add(&results, next_position, position);
    next_position = position;
  }
 
  do {
    #ifdef DEBUG_GET_CHANGED_RANGES
    printf("At [%-2u, %-2u] Compare ", position.extent.row + 1, position.extent.column);
    iterator_print_state(&old_iter);
    printf("\tvs\t");
    iterator_print_state(&new_iter);
    puts("");
    #endif
 
    // Compare the old and new subtrees.
    IteratorComparison comparison = iterator_compare(&old_iter, &new_iter);
 
    // Even if the two subtrees appear to be identical, they could differ
    // internally if they contain a range of text that was previously
    // excluded from the parse, and is now included, or vice-versa.
    if (comparison == IteratorMatches && ts_range_array_intersects(
      included_range_differences,
      included_range_difference_index,
      position.bytes,
      iterator_end_position(&old_iter).bytes
    )) {
      comparison = IteratorMayDiffer;
    }
 
    bool is_changed = false;
    switch (comparison) {
      // If the subtrees are definitely identical, move to the end
      // of both subtrees.
      case IteratorMatches:
        next_position = iterator_end_position(&old_iter);
        break;
 
      // If the subtrees might differ internally, descend into both
      // subtrees, finding the first child that spans the current position.
      case IteratorMayDiffer:
        if (iterator_descend(&old_iter, position.bytes)) {
          if (!iterator_descend(&new_iter, position.bytes)) {
            is_changed = true;
            next_position = iterator_end_position(&old_iter);
          }
        } else if (iterator_descend(&new_iter, position.bytes)) {
          is_changed = true;
          next_position = iterator_end_position(&new_iter);
        } else {
          next_position = length_min(
            iterator_end_position(&old_iter),
            iterator_end_position(&new_iter)
          );
        }
        break;
 
      // If the subtrees are different, record a change and then move
      // to the end of both subtrees.
      case IteratorDiffers:
        is_changed = true;
        next_position = length_min(
          iterator_end_position(&old_iter),
          iterator_end_position(&new_iter)
        );
        break;
    }
 
    // Ensure that both iterators are caught up to the current position.
    while (
      !iterator_done(&old_iter) &&
      iterator_end_position(&old_iter).bytes <= next_position.bytes
    ) iterator_advance(&old_iter);
    while (
      !iterator_done(&new_iter) &&
      iterator_end_position(&new_iter).bytes <= next_position.bytes
    ) iterator_advance(&new_iter);
 
    // Ensure that both iterators are at the same depth in the tree.
    while (old_iter.visible_depth > new_iter.visible_depth) {
      iterator_ascend(&old_iter);
    }
    while (new_iter.visible_depth > old_iter.visible_depth) {
      iterator_ascend(&new_iter);
    }
 
    if (is_changed) {
      #ifdef DEBUG_GET_CHANGED_RANGES
      printf(
        "  change: [[%u, %u] - [%u, %u]]\n",
        position.extent.row + 1, position.extent.column,
        next_position.extent.row + 1, next_position.extent.column
      );
      #endif
 
      ts_range_array_add(&results, position, next_position);
    }
 
    position = next_position;
 
    // Keep track of the current position in the included range differences
    // array in order to avoid scanning the entire array on each iteration.
    while (included_range_difference_index < included_range_differences->size) {
      const TSRange *range = &included_range_differences->contents[
        included_range_difference_index
      ];
      if (range->end_byte <= position.bytes) {
        included_range_difference_index++;
      } else {
        break;
      }
    }
  } while (!iterator_done(&old_iter) && !iterator_done(&new_iter));
 
  Length old_size = ts_subtree_total_size(*old_tree);
  Length new_size = ts_subtree_total_size(*new_tree);
  if (old_size.bytes < new_size.bytes) {
    ts_range_array_add(&results, old_size, new_size);
  } else if (new_size.bytes < old_size.bytes) {
    ts_range_array_add(&results, new_size, old_size);
  }
 
  *cursor1 = old_iter.cursor;
  *cursor2 = new_iter.cursor;
  *ranges = results.contents;
  return results.size;
}

References array_new, bytes, Length::bytes, TSPoint::column, Iterator::cursor, Length::extent, iterator_advance(), iterator_ascend(), iterator_compare(), iterator_descend(), iterator_done(), iterator_end_position(), iterator_new(), iterator_start_position(), IteratorDiffers, IteratorMatches, IteratorMayDiffer, length_min(), printf(), capstone::range, TSPoint::row, ts_range_array_add(), ts_range_array_intersects(), ts_subtree_total_size(), and Iterator::visible_depth.

Referenced by ts_tree_get_changed_ranges().