fix(treesitter): correctly handle query quantifiers (#24738)

Query patterns can contain quantifiers (e.g. (foo)+ @bar), so a single
capture can map to multiple nodes. The iter_matches API can not handle
this situation because the match table incorrectly maps capture indices
to a single node instead of to an array of nodes.

The match table should be updated to map capture indices to an array of
nodes. However, this is a massively breaking change, so must be done
with a proper deprecation period.

`iter_matches`, `add_predicate` and `add_directive` must opt-in to the
correct behavior for backward compatibility. This is done with a new
"all" option. This option will become the default and removed after the
0.10 release.

Co-authored-by: Christian Clason <c.clason@uni-graz.at>
Co-authored-by: MDeiml <matthias@deiml.net>
Co-authored-by: Gregory Anders <greg@gpanders.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/test/functional/treesitter/highlight_spec.lua b/test/functional/treesitter/highlight_spec.lua
index 932af0332b..10fe08c549 100644
--- a/test/functional/treesitter/highlight_spec.lua
+++ b/test/functional/treesitter/highlight_spec.lua
@@ -731,6 +731,31 @@ describe('treesitter highlighting (C)', function()
     eq(3, get_hl '@foo.missing.exists.bar')
     eq(nil, get_hl '@total.nonsense.but.a.lot.of.dots')
   end)
+
+  it('supports multiple nodes assigned to the same capture #17060', function()
+    insert([[
+      int x = 4;
+      int y = 5;
+      int z = 6;
+    ]])
+
+    exec_lua([[
+      local query = '((declaration)+ @string)'
+      vim.treesitter.query.set('c', 'highlights', query)
+      vim.treesitter.highlighter.new(vim.treesitter.get_parser(0, 'c'))
+    ]])
+
+    screen:expect {
+      grid = [[
+        {5:int x = 4;}                                                     |
+        {5:int y = 5;}                                                     |
+        {5:int z = 6;}                                                     |
+      ^                                                                 |
+      {1:~                                                                }|*13
+                                                                       |
+    ]],
+    }
+  end)
 end)
 
 describe('treesitter highlighting (help)', function()