feat(treesitter)!: default to correct behavior for quantified captures (#30193)

For context, see https://github.com/neovim/neovim/pull/24738. Before
that PR, Nvim did not correctly handle captures with quantifiers. That
PR made the correct behavior opt-in to minimize breaking changes, with
the intention that the correct behavior would eventually become the
default. Users can still opt-in to the old (incorrect) behavior for now,
but this option will eventually be removed completely.

BREAKING CHANGE: Any plugin which uses `Query:iter_matches()` must
update their call sites to expect an array of nodes in the `match`
table, rather than a single node.

9 files changed, 42 insertions, 68 deletions

diff --git a/runtime/doc/news.txt b/runtime/doc/news.txt
index b7e1e0c84f..21a8d2bd91 100644
--- a/runtime/doc/news.txt
+++ b/runtime/doc/news.txt
@@ -89,7 +89,11 @@ PLUGINS
 
 TREESITTER
 
-• TODO
+• |Query:iter_matches()| correctly returns all matching nodes in a match
+  instead of only the last node. This means that the returned table maps
+  capture IDs to a list of nodes that need to be iterated over. For
+  backwards compatibility, an option `all=false` (only return the last
+  matching node) is provided that will be removed in a future release.
 
 TUI
 
diff --git a/runtime/doc/treesitter.txt b/runtime/doc/treesitter.txt
index d9b71c4b5b..fea469e63b 100644
--- a/runtime/doc/treesitter.txt
+++ b/runtime/doc/treesitter.txt
@@ -1036,9 +1036,8 @@ add_directive({name}, {handler}, {opts})
                      the same name
                    • {all}? (`boolean`) Use the correct implementation of the
                      match table where capture IDs map to a list of nodes
-                     instead of a single node. Defaults to false (for backward
-                     compatibility). This option will eventually become the
-                     default and removed.
+                     instead of a single node. Defaults to true. This option
+                     will be removed in a future release.
 
                                         *vim.treesitter.query.add_predicate()*
 add_predicate({name}, {handler}, {opts})
@@ -1049,14 +1048,13 @@ add_predicate({name}, {handler}, {opts})
       • {handler}  (`fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata)`)
                    • see |vim.treesitter.query.add_directive()| for argument
                      meanings
-      • {opts}     (`table`) A table with the following fields:
+      • {opts}     (`table?`) A table with the following fields:
                    • {force}? (`boolean`) Override an existing predicate of
                      the same name
                    • {all}? (`boolean`) Use the correct implementation of the
                      match table where capture IDs map to a list of nodes
-                     instead of a single node. Defaults to false (for backward
-                     compatibility). This option will eventually become the
-                     default and removed.
+                     instead of a single node. Defaults to true. This option
+                     will be removed in a future release.
 
 edit({lang})                                     *vim.treesitter.query.edit()*
     Opens a live editor to query the buffer you started from.
@@ -1216,14 +1214,8 @@ Query:iter_matches({node}, {source}, {start}, {stop}, {opts})
     indices to a list of nodes, and metadata from any directives processing
     the match.
 
-    WARNING: Set `all=true` to ensure all matching nodes in a match are
-    returned, otherwise only the last node in a match is returned, breaking
-    captures involving quantifiers such as `(comment)+ @comment`. The default
-    option `all=false` is only provided for backward compatibility and will be
-    removed after Nvim 0.10.
-
     Example: >lua
-        for pattern, match, metadata in cquery:iter_matches(tree:root(), bufnr, 0, -1, { all = true }) do
+        for pattern, match, metadata in cquery:iter_matches(tree:root(), bufnr, 0, -1) do
           for id, nodes in pairs(match) do
             local name = query.captures[id]
             for _, node in ipairs(nodes) do
@@ -1248,12 +1240,11 @@ Query:iter_matches({node}, {source}, {start}, {stop}, {opts})
                     start depth for each match. This is used to prevent
                     traversing too deep into a tree.
                   • match_limit (integer) Set the maximum number of
-                    in-progress matches (Default: 256).
-                  • all (boolean) When set, the returned match table maps
-                    capture IDs to a list of nodes. Older versions of
-                    iter_matches incorrectly mapped capture IDs to a single
-                    node, which is incorrect behavior. This option will
-                    eventually become the default and removed.
+                    in-progress matches (Default: 256). all (boolean) When
+                    `false` (default `true`), the returned table maps capture
+                    IDs to a single (last) node instead of the full list of
+                    matching nodes. This option is only for backward
+                    compatibility and will be removed in a future release.
 
     Return: ~
         (`fun(): integer, table<integer, TSNode[]>, vim.treesitter.query.TSMetadata`)
diff --git a/runtime/lua/vim/treesitter/_fold.lua b/runtime/lua/vim/treesitter/_fold.lua
index 27590eff5d..7375beaf9d 100644
--- a/runtime/lua/vim/treesitter/_fold.lua
+++ b/runtime/lua/vim/treesitter/_fold.lua
@@ -131,9 +131,7 @@ local function compute_folds_levels(bufnr, info, srow, erow, parse_injections)
 
     -- Collect folds starting from srow - 1, because we should first subtract the folds that end at
     -- srow - 1 from the level of srow - 1 to get accurate level of srow.
-    for _, match, metadata in
-      query:iter_matches(tree:root(), bufnr, math.max(srow - 1, 0), erow, { all = true })
-    do
+    for _, match, metadata in query:iter_matches(tree:root(), bufnr, math.max(srow - 1, 0), erow) do
       for id, nodes in pairs(match) do
         if query.captures[id] == 'fold' then
           local range = ts.get_range(nodes[1], bufnr, metadata[id])
diff --git a/runtime/lua/vim/treesitter/_query_linter.lua b/runtime/lua/vim/treesitter/_query_linter.lua
index 8654b89c9b..ea1ae5416a 100644
--- a/runtime/lua/vim/treesitter/_query_linter.lua
+++ b/runtime/lua/vim/treesitter/_query_linter.lua
@@ -176,7 +176,7 @@ function M.lint(buf, opts)
     parser:parse()
     parser:for_each_tree(function(tree, ltree)
       if ltree:lang() == 'query' then
-        for _, match, _ in query:iter_matches(tree:root(), buf, 0, -1, { all = true }) do
+        for _, match, _ in query:iter_matches(tree:root(), buf, 0, -1) do
           local lang_context = {
             lang = lang,
             parser_info = parser_info,
diff --git a/runtime/lua/vim/treesitter/languagetree.lua b/runtime/lua/vim/treesitter/languagetree.lua
index d43a0a5d0b..cc9ffeaa29 100644
--- a/runtime/lua/vim/treesitter/languagetree.lua
+++ b/runtime/lua/vim/treesitter/languagetree.lua
@@ -833,13 +833,7 @@ function LanguageTree:_get_injections()
     local start_line, _, end_line, _ = root_node:range()
 
     for pattern, match, metadata in
-      self._injection_query:iter_matches(
-        root_node,
-        self._source,
-        start_line,
-        end_line + 1,
-        { all = true }
-      )
+      self._injection_query:iter_matches(root_node, self._source, start_line, end_line + 1)
     do
       local lang, combined, ranges = self:_get_injection(match, metadata)
       if lang then
diff --git a/runtime/lua/vim/treesitter/query.lua b/runtime/lua/vim/treesitter/query.lua
index 8e21353154..bd0574b8b7 100644
--- a/runtime/lua/vim/treesitter/query.lua
+++ b/runtime/lua/vim/treesitter/query.lua
@@ -620,8 +620,8 @@ local directive_handlers = {
 --- @field force? boolean
 ---
 --- Use the correct implementation of the match table where capture IDs map to
---- a list of nodes instead of a single node. Defaults to false (for backward
---- compatibility). This option will eventually become the default and removed.
+--- a list of nodes instead of a single node. Defaults to true. This option will
+--- be removed in a future release.
 --- @field all? boolean
 
 --- Adds a new predicate to be used in queries
@@ -629,7 +629,7 @@ local directive_handlers = {
 ---@param name string Name of the predicate, without leading #
 ---@param handler fun(match: table<integer,TSNode[]>, pattern: integer, source: integer|string, predicate: any[], metadata: vim.treesitter.query.TSMetadata)
 ---   - see |vim.treesitter.query.add_directive()| for argument meanings
----@param opts vim.treesitter.query.add_predicate.Opts
+---@param opts? vim.treesitter.query.add_predicate.Opts
 function M.add_predicate(name, handler, opts)
   -- Backward compatibility: old signature had "force" as boolean argument
   if type(opts) == 'boolean' then
@@ -642,7 +642,7 @@ function M.add_predicate(name, handler, opts)
     error(string.format('Overriding existing predicate %s', name))
   end
 
-  if opts.all then
+  if opts.all ~= false then
     predicate_handlers[name] = handler
   else
     --- @param match table<integer, TSNode[]>
@@ -894,16 +894,10 @@ end
 --- index of the pattern in the query, a table mapping capture indices to a list
 --- of nodes, and metadata from any directives processing the match.
 ---
---- WARNING: Set `all=true` to ensure all matching nodes in a match are
---- returned, otherwise only the last node in a match is returned, breaking captures
---- involving quantifiers such as `(comment)+ @comment`. The default option
---- `all=false` is only provided for backward compatibility and will be removed
---- after Nvim 0.10.
----
 --- Example:
 ---
 --- ```lua
---- for pattern, match, metadata in cquery:iter_matches(tree:root(), bufnr, 0, -1, { all = true }) do
+--- for pattern, match, metadata in cquery:iter_matches(tree:root(), bufnr, 0, -1) do
 ---   for id, nodes in pairs(match) do
 ---     local name = query.captures[id]
 ---     for _, node in ipairs(nodes) do
@@ -925,9 +919,9 @@ end
 ---   - max_start_depth (integer) if non-zero, sets the maximum start depth
 ---     for each match. This is used to prevent traversing too deep into a tree.
 ---   - match_limit (integer) Set the maximum number of in-progress matches (Default: 256).
----   - all (boolean) When set, the returned match table maps capture IDs to a list of nodes.
----     Older versions of iter_matches incorrectly mapped capture IDs to a single node, which is
----     incorrect behavior. This option will eventually become the default and removed.
+--- - all (boolean) When `false` (default `true`), the returned table maps capture IDs to a single
+---   (last) node instead of the full list of matching nodes. This option is only for backward
+---   compatibility and will be removed in a future release.
 ---
 ---@return (fun(): integer, table<integer, TSNode[]>, vim.treesitter.query.TSMetadata): pattern id, match, metadata
 function Query:iter_matches(node, source, start, stop, opts)
@@ -960,10 +954,10 @@ function Query:iter_matches(node, source, start, stop, opts)
 
     local captures = match:captures()
 
-    if not opts.all then
+    if opts.all == false then
       -- Convert the match table into the old buggy version for backward
-      -- compatibility. This is slow. Plugin authors, if you're reading this, set the "all"
-      -- option!
+      -- compatibility. This is slow, but we only do it when the caller explicitly opted into it by
+      -- setting `all` to `false`.
       local old_match = {} ---@type table<integer, TSNode>
       for k, v in pairs(captures or {}) do
         old_match[k] = v[#v]
diff --git a/runtime/lua/vim/ui.lua b/runtime/lua/vim/ui.lua
index c2b19e92c0..2d3b828ea1 100644
--- a/runtime/lua/vim/ui.lua
+++ b/runtime/lua/vim/ui.lua
@@ -196,7 +196,7 @@ function M._get_urls()
     local query = vim.treesitter.query.get(lang, 'highlights')
     if query then
       local tree = assert(ltree:tree_for_range(range))
-      for _, match, metadata in query:iter_matches(tree:root(), bufnr, row, row + 1, { all = true }) do
+      for _, match, metadata in query:iter_matches(tree:root(), bufnr, row, row + 1) do
         for id, nodes in pairs(match) do
           for _, node in ipairs(nodes) do
             if vim.treesitter.node_contains(node, range) then
diff --git a/test/functional/treesitter/parser_spec.lua b/test/functional/treesitter/parser_spec.lua
index 46e6a6002a..4aa8beebae 100644
--- a/test/functional/treesitter/parser_spec.lua
+++ b/test/functional/treesitter/parser_spec.lua
@@ -591,8 +591,7 @@ print()
             vim.treesitter.query.parse('c', '((number_literal) @number (#set! "key" "value"))')
           local parser = vim.treesitter.get_parser(0, 'c')
 
-          local _, _, metadata =
-            query:iter_matches(parser:parse()[1]:root(), 0, 0, -1, { all = true })()
+          local _, _, metadata = query:iter_matches(parser:parse()[1]:root(), 0, 0, -1)()
           return metadata.key
         end)
 
@@ -612,8 +611,7 @@ print()
             )
             local parser = vim.treesitter.get_parser(0, 'c')
 
-            local _, _, metadata =
-              query:iter_matches(parser:parse()[1]:root(), 0, 0, -1, { all = true })()
+            local _, _, metadata = query:iter_matches(parser:parse()[1]:root(), 0, 0, -1)()
             local _, nested_tbl = next(metadata)
             return nested_tbl.key
           end)
@@ -633,8 +631,7 @@ print()
             )
             local parser = vim.treesitter.get_parser(0, 'c')
 
-            local _, _, metadata =
-              query:iter_matches(parser:parse()[1]:root(), 0, 0, -1, { all = true })()
+            local _, _, metadata = query:iter_matches(parser:parse()[1]:root(), 0, 0, -1)()
             local _, nested_tbl = next(metadata)
             return nested_tbl
           end)
diff --git a/test/functional/treesitter/query_spec.lua b/test/functional/treesitter/query_spec.lua
index 00e8071738..d8338c1335 100644
--- a/test/functional/treesitter/query_spec.lua
+++ b/test/functional/treesitter/query_spec.lua
@@ -138,7 +138,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14, { all = true }) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14) do
         -- can't transmit node over RPC. just check the name and range
         local mrepr = {}
         for cid, nodes in pairs(match) do
@@ -211,7 +211,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14, { all = true }) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14) do
         -- can't transmit node over RPC. just check the name and range
         local mrepr = {}
         for cid, nodes in pairs(match) do
@@ -260,7 +260,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14, { all = true }) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14) do
         -- can't transmit node over RPC. just check the name and range
         local mrepr = {}
         for cid, nodes in pairs(match) do
@@ -307,7 +307,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 0, -1, { all = true }) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 0, -1) do
         -- can't transmit node over RPC. just check the name and range
         local mrepr = {}
         for cid, nodes in pairs(match) do
@@ -418,7 +418,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 0, -1, { all = true }) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 0, -1) do
         -- can't transmit node over RPC. just check the name and range
         local mrepr = {}
         for cid, nodes in pairs(match) do
@@ -464,11 +464,7 @@ void ui_refresh(void)
 
         local parser = vim.treesitter.get_parser(0, 'c')
 
-        -- Time bomb: update this in 0.12
-        if vim.fn.has('nvim-0.12') == 1 then
-          return 'Update this test to remove this message and { all = true } from add_predicate'
-        end
-        query.add_predicate('is-main?', is_main, { all = true })
+        query.add_predicate('is-main?', is_main)
 
         local query0 = query.parse('c', custom_query0)
 
@@ -496,7 +492,7 @@ void ui_refresh(void)
 
         local parser = vim.treesitter.get_parser(0, 'c')
 
-        query.add_predicate('is-main?', is_main, true)
+        query.add_predicate('is-main?', is_main, { all = false, force = true })
 
         local query0 = query.parse('c', custom_query0)
 
@@ -650,7 +646,7 @@ void ui_refresh(void)
       local parser = vim.treesitter.get_parser(0, 'c')
       local tree = parser:parse()[1]
       local res = {}
-      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14) do
+      for pattern, match in cquery:iter_matches(tree:root(), 0, 7, 14, { all = false }) do
         local mrepr = {}
         for cid, node in pairs(match) do
           table.insert(mrepr, { '@' .. cquery.captures[cid], node:type(), node:range() })