2 files changed, 81 insertions, 0 deletions
diff --git a/test/functional/fixtures/fake-lsp-server.lua b/test/functional/fixtures/fake-lsp-server.lua
index bd59e5dc1f..5403405905 100644
--- a/test/functional/fixtures/fake-lsp-server.lua
+++ b/test/functional/fixtures/fake-lsp-server.lua
@@ -744,6 +744,26 @@ function tests.clientside_commands()
   }
 end
 
+
+function tests.basic_formatting()
+  skeleton {
+    on_init = function()
+      return {
+        capabilities = {
+          documentFormattingProvider = true,
+        }
+      }
+    end;
+    body = function()
+      notify('start')
+      expect_request('textDocument/formatting', function()
+        return nil, {}
+      end)
+      notify('shutdown')
+    end;
+  }
+end
+
 -- Tests will be indexed by TEST_NAME
 
 local kill_timer = vim.loop.new_timer()
diff --git a/test/functional/plugin/lsp_spec.lua b/test/functional/plugin/lsp_spec.lua
index 6cde96ceaf..6e28946cc4 100644
--- a/test/functional/plugin/lsp_spec.lua
+++ b/test/functional/plugin/lsp_spec.lua
@@ -2773,4 +2773,65 @@ describe('LSP', function()
       }
     end)
   end)
+
+  describe("vim.lsp.buf.format", function()
+    it("Aborts with notify if no client matches filter", function()
+      local client
+      test_rpc_server {
+        test_name = "basic_init",
+        on_init = function(c)
+          client = c
+        end,
+        on_handler = function()
+          local notify_msg = exec_lua([[
+            local bufnr = vim.api.nvim_get_current_buf()
+            vim.lsp.buf_attach_client(bufnr, TEST_RPC_CLIENT_ID)
+            local notify_msg
+            local notify = vim.notify
+            vim.notify = function(msg, log_level)
+              notify_msg = msg
+            end
+            vim.lsp.buf.format({ name = 'does-not-exist' })
+            vim.notify = notify
+            return notify_msg
+          ]])
+          eq("[LSP] Format request failed, no matching language servers.", notify_msg)
+          client.stop()
+        end,
+      }
+    end)
+    it("Sends textDocument/formatting request to format buffer", function()
+      local expected_handlers = {
+        {NIL, {}, {method="shutdown", client_id=1}};
+        {NIL, {}, {method="start", client_id=1}};
+      }
+      local client
+      test_rpc_server {
+        test_name = "basic_formatting",
+        on_init = function(c)
+          client = c
+        end,
+        on_handler = function(_, _, ctx)
+          table.remove(expected_handlers)
+          if ctx.method == "start" then
+            local notify_msg = exec_lua([[
+              local bufnr = vim.api.nvim_get_current_buf()
+              vim.lsp.buf_attach_client(bufnr, TEST_RPC_CLIENT_ID)
+              local notify_msg
+              local notify = vim.notify
+              vim.notify = function(msg, log_level)
+                notify_msg = msg
+              end
+              vim.lsp.buf.format({ bufnr = bufnr })
+              vim.notify = notify
+              return notify_msg
+            ]])
+            eq(NIL, notify_msg)
+          elseif ctx.method == "shutdown" then
+            client.stop()
+          end
+        end,
+      }
+    end)
+  end)
 end)