traxys/tree-sitter
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Allow queries to match on supertypes

Browse source 
Co-authored-by: Ayman Nadeem <aymannadeem@github.com>
This commit is contained in:
Max Brunsfeld 2020-09-21 12:34:48 -07:00
parent f10a8448ed
commit b5a9adb555
8 changed files with 155 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

44
lib/src/tree_cursor.c
View file

@ -352,6 +352,50 @@ TSFieldId ts_tree_cursor_current_status(
return result;
}
bool ts_tree_cursor_has_supertype(
const TSTreeCursor *_self,
TSSymbol supertype_symbol
) {
const TreeCursor *self = (const TreeCursor *)_self;
// Walk up the tree, visiting the current node and its invisible ancestors,
// because fields can refer to nodes through invisible *wrapper* nodes,
for (unsigned i = self->stack.size - 1; i > 0; i--) {
TreeCursorEntry *entry = &self->stack.contents[i];
TreeCursorEntry *parent_entry = &self->stack.contents[i - 1];
const TSSymbol *alias_sequence = ts_language_alias_sequence(
self->tree->language,
parent_entry->subtree->ptr->production_id
);
// If the subtree is visible, return its public-facing symbol.
// Otherwise, return zero.
#define subtree_visible_symbol(subtree, structural_child_index) \
(( \
!ts_subtree_extra(subtree) && \
alias_sequence && \
alias_sequence[structural_child_index] \
) ? \
alias_sequence[structural_child_index] : \
ts_subtree_visible(subtree) ? \
ts_subtree_symbol(subtree) : \
0) \
// Stop walking up when a visible ancestor is found.
if (
i != self->stack.size - 1 &&
subtree_visible_symbol(*entry->subtree, entry->structural_child_index)
) break;
if (ts_subtree_symbol(*entry->subtree) == supertype_symbol) {
return true;
}
}
return false;
}
TSFieldId ts_tree_cursor_current_field_id(const TSTreeCursor *_self) {
const TreeCursor *self = (const TreeCursor *)_self;