feat(lsp): static registration support (#34371)

runtime/lua/vim/lsp/client.lua

@@ -554,6 +554,8 @@ function Client:initialize()
       assert(result.capabilities, "initialize result doesn't contain capabilities")
     self.server_capabilities = assert(lsp.protocol.resolve_capabilities(self.server_capabilities))
 
+    self:_process_static_registrations()
+
     if self.server_capabilities.positionEncoding then
       self.offset_encoding = self.server_capabilities.positionEncoding
     end
@@ -585,6 +587,48 @@ function Client:initialize()
   end)
 end
 
+-- Server capabilities for methods that support static registration.
+local static_registration_capabilities = {
+  [ms.textDocument_prepareCallHierarchy] = 'callHierarchyProvider',
+  [ms.textDocument_documentColor] = 'colorProvider',
+  [ms.textDocument_declaration] = 'declarationProvider',
+  [ms.textDocument_diagnostic] = 'diagnosticProvider',
+  [ms.textDocument_foldingRange] = 'foldingRangeProvider',
+  [ms.textDocument_implementation] = 'implementationProvider',
+  [ms.textDocument_inlayHint] = 'inlayHintProvider',
+  [ms.textDocument_inlineValue] = 'inlineValueProvider',
+  [ms.textDocument_linkedEditingRange] = 'linkedEditingRangeProvider',
+  [ms.textDocument_moniker] = 'monikerProvider',
+  [ms.textDocument_selectionRange] = 'selectionRangeProvider',
+  [ms.textDocument_semanticTokens_full] = 'semanticTokensProvider',
+  [ms.textDocument_typeDefinition] = 'typeDefinitionProvider',
+  [ms.textDocument_prepareTypeHierarchy] = 'typeHierarchyProvider',
+}
+
+--- @private
+function Client:_process_static_registrations()
+  local static_registrations = {} ---@type lsp.Registration[]
+
+  for method, capability in pairs(static_registration_capabilities) do
+    if
+      vim.tbl_get(self.server_capabilities, capability, 'id')
+      and self:_supports_registration(method)
+    then
+      static_registrations[#static_registrations + 1] = {
+        id = self.server_capabilities[capability].id,
+        method = method,
+        registerOptions = {
+          documentSelector = self.server_capabilities[capability].documentSelector, ---@type lsp.DocumentSelector?
+        },
+      }
+    end
+  end
+
+  if next(static_registrations) then
+    self:_register_dynamic(static_registrations)
+  end
+end
+
 --- @private
 --- Returns the handler associated with an LSP method.
 --- Returns the default handler if the user hasn't set a custom one.

test/functional/plugin/lsp_spec.lua

@@ -5727,6 +5727,28 @@ describe('LSP', function()
       eq({ method = 'textDocument/rangeFormatting', supported = true, fname = tmpfile }, result[4])
       eq({ method = 'textDocument/completion', supported = false }, result[5])
     end)
+
+    it('supports static registration', function()
+      exec_lua(create_server_definition)
+
+      local client_id = exec_lua(function()
+        local server = _G._create_server({
+          capabilities = {
+            colorProvider = { id = 'color-registration' },
+          },
+        })
+
+        return assert(vim.lsp.start({ name = 'dynamic-test', cmd = server.cmd }))
+      end)
+
+      eq(
+        true,
+        exec_lua(function()
+          local client = assert(vim.lsp.get_client_by_id(client_id))
+          return client.dynamic_capabilities:get('textDocument/documentColor') ~= nil
+        end)
+      )
+    end)
   end)
 
   describe('vim.lsp._watchfiles', function()