refactor(lsp): move glob parsing to util (#26519)

refactor(lsp): move glob parsing to vim.glob

Moving the logic for using vim.lpeg to create a match pattern from a
glob into `vim.glob`. There are several places in the LSP spec that
use globs, and it's very useful to have glob matching as a
generally-available utility.

6 files changed, 97 insertions, 92 deletions

diff --git a/runtime/lua/vim/_init_packages.lua b/runtime/lua/vim/_init_packages.lua
index 4a961970cc..f8710f7fd7 100644
--- a/runtime/lua/vim/_init_packages.lua
+++ b/runtime/lua/vim/_init_packages.lua
@@ -55,6 +55,7 @@ vim._submodules = {
   inspect = true,
   version = true,
   fs = true,
+  glob = true,
   iter = true,
   re = true,
   text = true,
diff --git a/runtime/lua/vim/_meta.lua b/runtime/lua/vim/_meta.lua
index bb9ed722e2..4c50627fe4 100644
--- a/runtime/lua/vim/_meta.lua
+++ b/runtime/lua/vim/_meta.lua
@@ -11,6 +11,7 @@ vim.diagnostic = require('vim.diagnostic')
 vim.filetype = require('vim.filetype')
 vim.fs = require('vim.fs')
 vim.func = require('vim.func')
+vim.glob = require('vim.glob')
 vim.health = require('vim.health')
 vim.highlight = require('vim.highlight')
 vim.iter = require('vim.iter')
diff --git a/runtime/lua/vim/glob.lua b/runtime/lua/vim/glob.lua
new file mode 100644
index 0000000000..731179d727
--- /dev/null
+++ b/runtime/lua/vim/glob.lua
@@ -0,0 +1,81 @@
+local lpeg = vim.lpeg
+
+local M = {}
+
+--- Parses a raw glob into an |lpeg| pattern.
+---
+--- This uses glob semantics from LSP 3.17.0: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#pattern
+--- Glob patterns can have the following syntax:
+--- `*` to match one or more characters in a path segment
+--- `?` to match on one character in a path segment
+--- `**` to match any number of path segments, including none
+--- `{}` to group conditions (e.g. `**​/*.{ts,js}` matches all TypeScript and JavaScript files)
+--- `[]` to declare a range of characters to match in a path segment (e.g., `example.[0-9]` to match on `example.0`, `example.1`, …)
+--- `[!...]` to negate a range of characters to match in a path segment (e.g., `example.[!0-9]` to match on `example.a`, `example.b`, but not `example.0`)
+---@param pattern string The raw glob pattern
+---@return vim.lpeg.Pattern pattern An |lpeg| representation of the pattern
+function M.to_lpeg(pattern)
+  local l = lpeg
+
+  local P, S, V = lpeg.P, lpeg.S, lpeg.V
+  local C, Cc, Ct, Cf = lpeg.C, lpeg.Cc, lpeg.Ct, lpeg.Cf
+
+  local pathsep = '/'
+
+  local function class(inv, ranges)
+    for i, r in ipairs(ranges) do
+      ranges[i] = r[1] .. r[2]
+    end
+    local patt = l.R(unpack(ranges))
+    if inv == '!' then
+      patt = P(1) - patt
+    end
+    return patt
+  end
+
+  local function add(acc, a)
+    return acc + a
+  end
+
+  local function mul(acc, m)
+    return acc * m
+  end
+
+  local function star(stars, after)
+    return (-after * (l.P(1) - pathsep)) ^ #stars * after
+  end
+
+  local function dstar(after)
+    return (-after * l.P(1)) ^ 0 * after
+  end
+
+  local p = P({
+    'Pattern',
+    Pattern = V('Elem') ^ -1 * V('End'),
+    Elem = Cf(
+      (V('DStar') + V('Star') + V('Ques') + V('Class') + V('CondList') + V('Literal'))
+        * (V('Elem') + V('End')),
+      mul
+    ),
+    DStar = P('**') * (P(pathsep) * (V('Elem') + V('End')) + V('End')) / dstar,
+    Star = C(P('*') ^ 1) * (V('Elem') + V('End')) / star,
+    Ques = P('?') * Cc(l.P(1) - pathsep),
+    Class = P('[') * C(P('!') ^ -1) * Ct(Ct(C(1) * '-' * C(P(1) - ']')) ^ 1 * ']') / class,
+    CondList = P('{') * Cf(V('Cond') * (P(',') * V('Cond')) ^ 0, add) * '}',
+    -- TODO: '*' inside a {} condition is interpreted literally but should probably have the same
+    -- wildcard semantics it usually has.
+    -- Fixing this is non-trivial because '*' should match non-greedily up to "the rest of the
+    -- pattern" which in all other cases is the entire succeeding part of the pattern, but at the end of a {}
+    -- condition means "everything after the {}" where several other options separated by ',' may
+    -- exist in between that should not be matched by '*'.
+    Cond = Cf((V('Ques') + V('Class') + V('CondList') + (V('Literal') - S(',}'))) ^ 1, mul)
+      + Cc(l.P(0)),
+    Literal = P(1) / l.P,
+    End = P(-1) * Cc(l.P(-1)),
+  })
+
+  local lpeg_pattern = p:match(pattern) --[[@as vim.lpeg.Pattern?]]
+  return assert(lpeg_pattern, 'Invalid glob')
+end
+
+return M
diff --git a/runtime/lua/vim/lsp/_dynamic.lua b/runtime/lua/vim/lsp/_dynamic.lua
index 04040e8e28..4bee58559f 100644
--- a/runtime/lua/vim/lsp/_dynamic.lua
+++ b/runtime/lua/vim/lsp/_dynamic.lua
@@ -1,4 +1,4 @@
-local wf = require('vim.lsp._watchfiles')
+local glob = require('vim.glob')
 
 --- @class lsp.DynamicCapabilities
 --- @field capabilities table<string, lsp.Registration[]>
@@ -97,7 +97,7 @@ function M.match(bufnr, documentSelector)
     if matches and filter.scheme and not vim.startswith(uri, filter.scheme .. ':') then
       matches = false
     end
-    if matches and filter.pattern and not wf._match(filter.pattern, fname) then
+    if matches and filter.pattern and not glob.to_lpeg(filter.pattern):match(fname) then
       matches = false
     end
     if matches then
diff --git a/runtime/lua/vim/lsp/_watchfiles.lua b/runtime/lua/vim/lsp/_watchfiles.lua
index 1fd112631d..af4cc65f71 100644
--- a/runtime/lua/vim/lsp/_watchfiles.lua
+++ b/runtime/lua/vim/lsp/_watchfiles.lua
@@ -1,4 +1,5 @@
 local bit = require('bit')
+local glob = require('vim.glob')
 local watch = require('vim._watch')
 local protocol = require('vim.lsp.protocol')
 local ms = protocol.Methods
@@ -6,88 +7,6 @@ local lpeg = vim.lpeg
 
 local M = {}
 
---- Parses the raw pattern into an |lpeg| pattern. LPeg patterns natively support the "this" or "that"
---- alternative constructions described in the LSP spec that cannot be expressed in a standard Lua pattern.
----
----@param pattern string The raw glob pattern
----@return vim.lpeg.Pattern? pattern An |lpeg| representation of the pattern, or nil if the pattern is invalid.
-local function parse(pattern)
-  local l = lpeg
-
-  local P, S, V = lpeg.P, lpeg.S, lpeg.V
-  local C, Cc, Ct, Cf = lpeg.C, lpeg.Cc, lpeg.Ct, lpeg.Cf
-
-  local pathsep = '/'
-
-  local function class(inv, ranges)
-    for i, r in ipairs(ranges) do
-      ranges[i] = r[1] .. r[2]
-    end
-    local patt = l.R(unpack(ranges))
-    if inv == '!' then
-      patt = P(1) - patt
-    end
-    return patt
-  end
-
-  local function add(acc, a)
-    return acc + a
-  end
-
-  local function mul(acc, m)
-    return acc * m
-  end
-
-  local function star(stars, after)
-    return (-after * (l.P(1) - pathsep)) ^ #stars * after
-  end
-
-  local function dstar(after)
-    return (-after * l.P(1)) ^ 0 * after
-  end
-
-  local p = P({
-    'Pattern',
-    Pattern = V('Elem') ^ -1 * V('End'),
-    Elem = Cf(
-      (V('DStar') + V('Star') + V('Ques') + V('Class') + V('CondList') + V('Literal'))
-        * (V('Elem') + V('End')),
-      mul
-    ),
-    DStar = P('**') * (P(pathsep) * (V('Elem') + V('End')) + V('End')) / dstar,
-    Star = C(P('*') ^ 1) * (V('Elem') + V('End')) / star,
-    Ques = P('?') * Cc(l.P(1) - pathsep),
-    Class = P('[') * C(P('!') ^ -1) * Ct(Ct(C(1) * '-' * C(P(1) - ']')) ^ 1 * ']') / class,
-    CondList = P('{') * Cf(V('Cond') * (P(',') * V('Cond')) ^ 0, add) * '}',
-    -- TODO: '*' inside a {} condition is interpreted literally but should probably have the same
-    -- wildcard semantics it usually has.
-    -- Fixing this is non-trivial because '*' should match non-greedily up to "the rest of the
-    -- pattern" which in all other cases is the entire succeeding part of the pattern, but at the end of a {}
-    -- condition means "everything after the {}" where several other options separated by ',' may
-    -- exist in between that should not be matched by '*'.
-    Cond = Cf((V('Ques') + V('Class') + V('CondList') + (V('Literal') - S(',}'))) ^ 1, mul)
-      + Cc(l.P(0)),
-    Literal = P(1) / l.P,
-    End = P(-1) * Cc(l.P(-1)),
-  })
-
-  return p:match(pattern) --[[@as vim.lpeg.Pattern?]]
-end
-
----@private
---- Implementation of LSP 3.17.0's pattern matching: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#pattern
----
----@param pattern string|vim.lpeg.Pattern The glob pattern (raw or parsed) to match.
----@param s string The string to match against pattern.
----@return boolean Whether or not pattern matches s.
-function M._match(pattern, s)
-  if type(pattern) == 'string' then
-    local p = assert(parse(pattern))
-    return p:match(s) ~= nil
-  end
-  return pattern:match(s) ~= nil
-end
-
 M._watchfunc = (vim.fn.has('win32') == 1 or vim.fn.has('mac') == 1) and watch.watch or watch.poll
 
 ---@type table<integer, table<string, function[]>> client id -> registration id -> cancel function
@@ -112,9 +31,9 @@ local to_lsp_change_type = {
 --- Default excludes the same as VSCode's `files.watcherExclude` setting.
 --- https://github.com/microsoft/vscode/blob/eef30e7165e19b33daa1e15e92fa34ff4a5df0d3/src/vs/workbench/contrib/files/browser/files.contribution.ts#L261
 ---@type vim.lpeg.Pattern parsed Lpeg pattern
-M._poll_exclude_pattern = parse('**/.git/{objects,subtree-cache}/**')
-  + parse('**/node_modules/*/**')
-  + parse('**/.hg/store/**')
+M._poll_exclude_pattern = glob.to_lpeg('**/.git/{objects,subtree-cache}/**')
+  + glob.to_lpeg('**/node_modules/*/**')
+  + glob.to_lpeg('**/.hg/store/**')
 
 --- Registers the workspace/didChangeWatchedFiles capability dynamically.
 ---
@@ -143,7 +62,7 @@ function M.register(reg, ctx)
     local glob_pattern = w.globPattern
 
     if type(glob_pattern) == 'string' then
-      local pattern = parse(glob_pattern)
+      local pattern = glob.to_lpeg(glob_pattern)
       if not pattern then
         error('Cannot parse pattern: ' .. glob_pattern)
       end
@@ -155,7 +74,7 @@ function M.register(reg, ctx)
       local base_uri = glob_pattern.baseUri
       local uri = type(base_uri) == 'string' and base_uri or base_uri.uri
       local base_dir = vim.uri_to_fname(uri)
-      local pattern = parse(glob_pattern.pattern)
+      local pattern = glob.to_lpeg(glob_pattern.pattern)
       if not pattern then
         error('Cannot parse pattern: ' .. glob_pattern.pattern)
       end
diff --git a/test/functional/plugin/lsp/watchfiles_spec.lua b/test/functional/lua/glob_spec.lua
index a8260e0c98..ce38d25e46 100644
--- a/test/functional/plugin/lsp/watchfiles_spec.lua
+++ b/test/functional/lua/glob_spec.lua
@@ -1,14 +1,17 @@
 local helpers = require('test.functional.helpers')(after_each)
-
 local eq = helpers.eq
 local exec_lua = helpers.exec_lua
 
-describe('vim.lsp._watchfiles', function()
+describe('glob', function()
   before_each(helpers.clear)
   after_each(helpers.clear)
 
   local match = function(...)
-    return exec_lua('return require("vim.lsp._watchfiles")._match(...)', ...)
+    return exec_lua([[
+      local pattern = select(1, ...)
+      local str = select(2, ...)
+      return require("vim.glob").to_lpeg(pattern):match(str) ~= nil
+    ]], ...)
   end
 
   describe('glob matching', function()