Merge remote-tracking branch 'upstream/master' into aucmd_textputpostaucmd_textputpost

15 files changed, 2804 insertions, 494 deletions

diff --git a/test/functional/plugin/editorconfig_spec.lua b/test/functional/plugin/editorconfig_spec.lua
index e6a2550aba..ac78003a8c 100644
--- a/test/functional/plugin/editorconfig_spec.lua
+++ b/test/functional/plugin/editorconfig_spec.lua
@@ -3,9 +3,9 @@ local clear = helpers.clear
 local command = helpers.command
 local eq = helpers.eq
 local pathsep = helpers.get_pathsep()
-local curbufmeths = helpers.curbufmeths
 local funcs = helpers.funcs
 local meths = helpers.meths
+local exec_lua = helpers.exec_lua
 
 local testdir = 'Xtest-editorconfig'
 
@@ -13,7 +13,7 @@ local function test_case(name, expected)
   local filename = testdir .. pathsep .. name
   command('edit ' .. filename)
   for opt, val in pairs(expected) do
-    eq(val, curbufmeths.get_option(opt), name)
+    eq(val, meths.get_option_value(opt, {buf=0}), name)
   end
 end
 
@@ -160,8 +160,8 @@ describe('editorconfig', function()
   end)
 
   it('sets newline options', function()
-    test_case('with_newline.txt', { fixendofline = true, endofline = true })
-    test_case('without_newline.txt', { fixendofline = false, endofline = false })
+    test_case('with_newline.txt', { fixendofline = true })
+    test_case('without_newline.txt', { fixendofline = false })
   end)
 
   it('respects trim_trailing_whitespace', function()
@@ -207,4 +207,15 @@ But not this one
     test_case('3_space.txt', { shiftwidth = 42 })
     test_case('4_space.py', { shiftwidth = 4 })
   end)
+
+  it('does not operate on invalid buffers', function()
+    local ok, err = unpack(exec_lua([[
+      vim.cmd.edit('test.txt')
+      local bufnr = vim.api.nvim_get_current_buf()
+      vim.cmd.bwipeout(bufnr)
+      return {pcall(require('editorconfig').config, bufnr)}
+    ]]))
+
+    eq(true, ok, err)
+  end)
 end)
diff --git a/test/functional/plugin/health_spec.lua b/test/functional/plugin/health_spec.lua
index 97d32313e5..50b1d03f36 100644
--- a/test/functional/plugin/health_spec.lua
+++ b/test/functional/plugin/health_spec.lua
@@ -1,5 +1,4 @@
 local helpers = require('test.functional.helpers')(after_each)
-local global_helpers = require('test.helpers')
 local Screen = require('test.functional.ui.screen')
 
 local clear = helpers.clear
@@ -43,20 +42,17 @@ end)
 describe('health.vim', function()
   before_each(function()
     clear{args={'-u', 'NORC'}}
-    -- Provides functions:
-    --    health#broken#check()
-    --    health#success1#check()
-    --    health#success2#check()
+    -- Provides healthcheck functions
     command("set runtimepath+=test/functional/fixtures")
   end)
 
   describe(":checkhealth", function()
-    it("functions health#report_*() render correctly", function()
+    it("functions report_*() render correctly", function()
       command("checkhealth full_render")
       helpers.expect([[
 
       ==============================================================================
-      full_render: health#full_render#check
+      test_plug.full_render: require("test_plug.full_render.health").check()
 
       report 1 ~
       - OK life is fine
@@ -79,7 +75,7 @@ describe('health.vim', function()
       helpers.expect([[
 
         ==============================================================================
-        success1: health#success1#check
+        test_plug: require("test_plug.health").check()
 
         report 1 ~
         - OK everything is fine
@@ -88,36 +84,19 @@ describe('health.vim', function()
         - OK nothing to see here
 
         ==============================================================================
-        success2: health#success2#check
-
-        another 1 ~
-        - OK ok
-
-        ==============================================================================
-        test_plug: require("test_plug.health").check()
+        test_plug.success1: require("test_plug.success1.health").check()
 
         report 1 ~
         - OK everything is fine
 
         report 2 ~
         - OK nothing to see here
-        ]])
-    end)
-
-    it("lua plugins, skips vimscript healthchecks with the same name", function()
-      command("checkhealth test_plug")
-      -- Existing file in test/functional/fixtures/lua/test_plug/autoload/health/test_plug.vim
-      -- and the Lua healthcheck is used instead.
-      helpers.expect([[
 
         ==============================================================================
-        test_plug: require("test_plug.health").check()
-
-        report 1 ~
-        - OK everything is fine
+        test_plug.success2: require("test_plug.success2.health").check()
 
-        report 2 ~
-        - OK nothing to see here
+        another 1 ~
+        - OK ok
         ]])
     end)
 
@@ -136,57 +115,6 @@ describe('health.vim', function()
         ]])
     end)
 
-    it("lua plugins submodules with expression '*'", function()
-      command("checkhealth test_plug*")
-      local buf_lines = helpers.curbuf('get_lines', 0, -1, true)
-      -- avoid dealing with path separators
-      local received = table.concat(buf_lines, '\n', 1, #buf_lines - 5)
-      local expected = helpers.dedent([[
-
-        ==============================================================================
-        test_plug: require("test_plug.health").check()
-
-        report 1 ~
-        - OK everything is fine
-
-        report 2 ~
-        - OK nothing to see here
-
-        ==============================================================================
-        test_plug.submodule: require("test_plug.submodule.health").check()
-
-        report 1 ~
-        - OK everything is fine
-
-        report 2 ~
-        - OK nothing to see here
-
-        ==============================================================================
-        test_plug.submodule_empty: require("test_plug.submodule_empty.health").check()
-
-        - ERROR The healthcheck report for "test_plug.submodule_empty" plugin is empty.
-
-        ==============================================================================
-        test_plug.submodule_failed: require("test_plug.submodule_failed.health").check()
-
-        - ERROR Failed to run healthcheck for "test_plug.submodule_failed" plugin. Exception:
-          function health#check, line 25]])
-      eq(expected, received)
-    end)
-
-    it("gracefully handles broken healthcheck", function()
-      command("checkhealth broken")
-      helpers.expect([[
-
-        ==============================================================================
-        broken: health#broken#check
-
-        - ERROR Failed to run healthcheck for "broken" plugin. Exception:
-          function health#check[25]..health#broken#check, line 1
-          caused an error
-        ]])
-    end)
-
     it("... including empty reports", function()
       command("checkhealth test_plug.submodule_empty")
       helpers.expect([[
@@ -198,36 +126,17 @@ describe('health.vim', function()
       ]])
     end)
 
-    it("gracefully handles broken lua healthcheck", function()
-      command("checkhealth test_plug.submodule_failed")
-      local buf_lines = helpers.curbuf('get_lines', 0, -1, true)
-      local received = table.concat(buf_lines, '\n', 1, #buf_lines - 5)
-      -- avoid dealing with path separators
-      local lua_err = "attempt to perform arithmetic on a nil value"
-      local last_line = buf_lines[#buf_lines - 4]
-      assert(string.find(last_line, lua_err) ~= nil, "Lua error not present")
-
-      local expected = global_helpers.dedent([[
-
-        ==============================================================================
-        test_plug.submodule_failed: require("test_plug.submodule_failed.health").check()
-
-        - ERROR Failed to run healthcheck for "test_plug.submodule_failed" plugin. Exception:
-          function health#check, line 25]])
-      eq(expected, received)
-    end)
-
     it("highlights OK, ERROR", function()
       local screen = Screen.new(50, 12)
       screen:attach()
       screen:set_default_attr_ids({
-        Ok = { foreground = Screen.colors.Grey3, background = 6291200 },
-        Error = { foreground = Screen.colors.Grey100, background = Screen.colors.Red },
+        Ok = { foreground = Screen.colors.LightGreen },
+        Error = { foreground = Screen.colors.Red },
         Heading = { foreground = tonumber('0x6a0dad') },
         Bar = { foreground = Screen.colors.LightGrey, background = Screen.colors.DarkGrey },
       })
       command("checkhealth foo success1")
-      command("set nowrap laststatus=0")
+      command("set nofoldenable nowrap laststatus=0")
       screen:expect{grid=[[
         ^                                                  |
         {Bar:──────────────────────────────────────────────────}|
@@ -236,7 +145,7 @@ describe('health.vim', function()
         - {Error:ERROR} No healthcheck found for "foo" plugin.    |
                                                           |
         {Bar:──────────────────────────────────────────────────}|
-        {Heading:success1: health#success1#check}                   |
+        {Heading:test_plug.success1: require("test_plug.success1.he}|
                                                           |
         {Heading:report 1}                                          |
         - {Ok:OK} everything is fine                           |
@@ -244,6 +153,22 @@ describe('health.vim', function()
       ]]}
     end)
 
+    it("fold healthchecks", function()
+      local screen = Screen.new(50, 7)
+      screen:attach()
+      command("checkhealth foo success1")
+      command("set nowrap laststatus=0")
+      screen:expect{grid=[[
+        ^                                                  |
+        ──────────────────────────────────────────────────|
+        +WE  4 lines: foo: ·······························|
+        ──────────────────────────────────────────────────|
+        +--  8 lines: test_plug.success1: require("test_pl|
+        ~                                                 |
+                                                          |
+      ]]}
+    end)
+
     it("gracefully handles invalid healthcheck", function()
       command("checkhealth non_existent_healthcheck")
       -- luacheck: ignore 613
diff --git a/test/functional/plugin/lsp/completion_spec.lua b/test/functional/plugin/lsp/completion_spec.lua
new file mode 100644
index 0000000000..9354654afe
--- /dev/null
+++ b/test/functional/plugin/lsp/completion_spec.lua
@@ -0,0 +1,239 @@
+---@diagnostic disable: no-unknown
+local helpers = require('test.functional.helpers')(after_each)
+local eq = helpers.eq
+local exec_lua = helpers.exec_lua
+
+
+--- Convert completion results.
+---
+---@param line string line contents. Mark cursor position with `|`
+---@param candidates lsp.CompletionList|lsp.CompletionItem[]
+---@param lnum? integer 0-based, defaults to 0
+---@return {items: table[], server_start_boundary: integer?}
+local function complete(line, candidates, lnum)
+  lnum = lnum or 0
+  -- nvim_win_get_cursor returns 0 based column, line:find returns 1 based
+  local cursor_col = line:find("|") - 1
+  line = line:gsub("|", "")
+  return exec_lua([[
+    local line, cursor_col, lnum, result = ...
+    local line_to_cursor = line:sub(1, cursor_col)
+    local client_start_boundary = vim.fn.match(line_to_cursor, '\\k*$')
+    local items, server_start_boundary = require("vim.lsp._completion")._convert_results(
+      line,
+      lnum,
+      cursor_col,
+      client_start_boundary,
+      nil,
+      result,
+      "utf-16"
+    )
+    return {
+      items = items,
+      server_start_boundary = server_start_boundary
+    }
+  ]], line, cursor_col, lnum, candidates)
+end
+
+
+describe("vim.lsp._completion", function()
+  before_each(helpers.clear)
+
+  -- https://microsoft.github.io/language-server-protocol/specifications/specification-current/#textDocument_completion
+  it('prefers textEdit over label as word', function()
+    local range0 = {
+      start = { line = 0, character = 0 },
+      ["end"] = { line = 0, character = 0 },
+    }
+    local completion_list = {
+      -- resolves into label
+      { label = 'foobar', sortText = 'a', documentation = 'documentation' },
+      {
+        label = 'foobar',
+        sortText = 'b',
+        documentation = { value = 'documentation' },
+      },
+      -- resolves into insertText
+      { label = 'foocar', sortText = 'c', insertText = 'foobar' },
+      { label = 'foocar', sortText = 'd', insertText = 'foobar' },
+      -- resolves into textEdit.newText
+      { label = 'foocar', sortText = 'e', insertText = 'foodar', textEdit = { newText = 'foobar', range = range0 } },
+      { label = 'foocar', sortText = 'f', textEdit = { newText = 'foobar', range = range0 } },
+      -- real-world snippet text
+      {
+        label = 'foocar',
+        sortText = 'g',
+        insertText = 'foodar',
+        insertTextFormat = 2,
+        textEdit = { newText = 'foobar(${1:place holder}, ${2:more ...holder{\\}})', range = range0 },
+      },
+      {
+        label = 'foocar',
+        sortText = 'h',
+        insertText = 'foodar(${1:var1} typ1, ${2:var2} *typ2) {$0\\}',
+        insertTextFormat = 2,
+      },
+      -- nested snippet tokens
+      {
+        label = 'foocar',
+        sortText = 'i',
+        insertText = 'foodar(${1:${2|typ1,typ2|}}) {$0\\}',
+        insertTextFormat = 2,
+      },
+      -- braced tabstop
+      { label = 'foocar', sortText = 'j', insertText = 'foodar()${0}', insertTextFormat = 2},
+      -- plain text
+      {
+        label = 'foocar',
+        sortText = 'k',
+        insertText = 'foodar(${1:var1})',
+        insertTextFormat = 1,
+      },
+    }
+    local expected = {
+      {
+        abbr = 'foobar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foobar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foobar',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foobar(place holder, more ...holder{})',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foodar(var1 typ1, var2 *typ2) {}',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foodar(typ1) {}',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foodar()',
+      },
+      {
+        abbr = 'foocar',
+        word = 'foodar(${1:var1})',
+      },
+    }
+    local result = complete('|', completion_list)
+    result = vim.tbl_map(function(x)
+      return {
+        abbr = x.abbr,
+        word = x.word
+      }
+    end, result.items)
+    eq(expected, result)
+  end)
+  it("uses correct start boundary", function()
+    local completion_list = {
+      isIncomplete = false,
+      items = {
+        {
+          filterText = "this_thread",
+          insertText = "this_thread",
+          insertTextFormat = 1,
+          kind = 9,
+          label = " this_thread",
+          score = 1.3205767869949,
+          sortText = "4056f757this_thread",
+          textEdit = {
+            newText = "this_thread",
+            range = {
+              start = { line = 0, character = 7 },
+              ["end"] = { line = 0, character = 11 },
+            },
+          }
+        },
+      }
+    }
+    local expected = {
+      abbr = ' this_thread',
+      dup = 1,
+      empty = 1,
+      icase = 1,
+      kind = 'Module',
+      menu = '',
+      word = 'this_thread',
+    }
+    local result = complete("  std::this|", completion_list)
+    eq(7, result.server_start_boundary)
+    local item = result.items[1]
+    item.user_data = nil
+    eq(expected, item)
+  end)
+
+  it("should search from start boundary to cursor position", function()
+    local completion_list = {
+      isIncomplete = false,
+      items = {
+        {
+          filterText = "this_thread",
+          insertText = "this_thread",
+          insertTextFormat = 1,
+          kind = 9,
+          label = " this_thread",
+          score = 1.3205767869949,
+          sortText = "4056f757this_thread",
+          textEdit = {
+            newText = "this_thread",
+            range = {
+              start = { line = 0, character = 7 },
+              ["end"] = { line = 0, character = 11 },
+            },
+          }
+        },
+        {
+          filterText = "notthis_thread",
+          insertText = "notthis_thread",
+          insertTextFormat = 1,
+          kind = 9,
+          label = " notthis_thread",
+          score = 1.3205767869949,
+          sortText = "4056f757this_thread",
+          textEdit = {
+            newText = "notthis_thread",
+            range = {
+              start = { line = 0, character = 7 },
+              ["end"] = { line = 0, character = 11 },
+            },
+          }
+        },
+      }
+    }
+    local expected = {
+      abbr = ' this_thread',
+      dup = 1,
+      empty = 1,
+      icase = 1,
+      kind = 'Module',
+      menu = '',
+      word = 'this_thread',
+    }
+    local result = complete("  std::this|is", completion_list)
+    eq(1, #result.items)
+    local item = result.items[1]
+    item.user_data = nil
+    eq(expected, item)
+  end)
+end)
diff --git a/test/functional/plugin/lsp/diagnostic_spec.lua b/test/functional/plugin/lsp/diagnostic_spec.lua
index f73ffc29b0..1da0222114 100644
--- a/test/functional/plugin/lsp/diagnostic_spec.lua
+++ b/test/functional/plugin/lsp/diagnostic_spec.lua
@@ -1,10 +1,13 @@
 local helpers = require('test.functional.helpers')(after_each)
+local lsp_helpers = require('test.functional.plugin.lsp.helpers')
 
 local clear = helpers.clear
 local exec_lua = helpers.exec_lua
 local eq = helpers.eq
 local neq = require('test.helpers').neq
 
+local create_server_definition = lsp_helpers.create_server_definition
+
 describe('vim.lsp.diagnostic', function()
   local fake_uri
 
@@ -81,6 +84,7 @@ describe('vim.lsp.diagnostic', function()
       local lines = {"1st line of text", "2nd line of text", "wow", "cool", "more", "lines"}
       vim.fn.bufload(diagnostic_bufnr)
       vim.api.nvim_buf_set_lines(diagnostic_bufnr, 0, 1, false, lines)
+      vim.api.nvim_win_set_buf(0, diagnostic_bufnr)
       return diagnostic_bufnr
     ]], fake_uri)
   end)
@@ -97,7 +101,6 @@ describe('vim.lsp.diagnostic', function()
         }
 
         diagnostics[1].code = 42
-        diagnostics[1].tags = {"foo", "bar"}
         diagnostics[1].data = "Hello world"
 
         vim.lsp.diagnostic.on_publish_diagnostics(nil, {
@@ -110,10 +113,9 @@ describe('vim.lsp.diagnostic', function()
           vim.lsp.diagnostic.get_line_diagnostics(diagnostic_bufnr, 1)[1],
         }
       ]]
-      eq({code = 42, tags = {"foo", "bar"}, data = "Hello world"}, result[1].user_data.lsp)
+      eq({code = 42, data = "Hello world"}, result[1].user_data.lsp)
       eq(42, result[1].code)
       eq(42, result[2].code)
-      eq({"foo", "bar"}, result[2].tags)
       eq("Hello world", result[2].data)
     end)
   end)
@@ -267,4 +269,155 @@ describe('vim.lsp.diagnostic', function()
       eq(exec_lua([[return #vim.diagnostic.get(...)]], bufnr), 0)
     end)
   end)
+
+  describe('vim.lsp.diagnostic.on_diagnostic', function()
+    before_each(function()
+      exec_lua(create_server_definition)
+      exec_lua([[
+        server = _create_server({
+          capabilities = {
+            diagnosticProvider = {
+            }
+          }
+        })
+
+        function get_extmarks(bufnr, client_id)
+          local namespace = vim.lsp.diagnostic.get_namespace(client_id, true)
+          local ns = vim.diagnostic.get_namespace(namespace)
+          local extmarks = {}
+          if ns.user_data.virt_text_ns then
+            for _, e in pairs(vim.api.nvim_buf_get_extmarks(bufnr, ns.user_data.virt_text_ns, 0, -1, {details=true})) do
+              table.insert(extmarks, e)
+            end
+          end
+          if ns.user_data.underline_ns then
+            for _, e in pairs(vim.api.nvim_buf_get_extmarks(bufnr, ns.user_data.underline_ns, 0, -1, {details=true})) do
+              table.insert(extmarks, e)
+            end
+          end
+          return extmarks
+        end
+
+        client_id = vim.lsp.start({ name = 'dummy', cmd = server.cmd })
+      ]])
+    end)
+
+    it('adds diagnostics to vim.diagnostics', function()
+      local diags = exec_lua([[
+        vim.lsp.diagnostic.on_diagnostic(nil,
+          {
+            kind = 'full',
+            items = {
+              make_error('Pull Diagnostic', 4, 4, 4, 4),
+            }
+          },
+          {
+            params = {
+              textDocument = { uri = fake_uri },
+            },
+            uri = fake_uri,
+            client_id = client_id,
+          },
+          {}
+        )
+
+        return vim.diagnostic.get(diagnostic_bufnr)
+      ]])
+      eq(1, #diags)
+      eq('Pull Diagnostic', diags[1].message)
+    end)
+
+    it('allows configuring the virtual text via vim.lsp.with', function()
+      local expected_spacing = 10
+      local extmarks = exec_lua(
+        [[
+        Diagnostic = vim.lsp.with(vim.lsp.diagnostic.on_diagnostic, {
+          virtual_text = {
+            spacing = ...,
+          },
+        })
+
+        Diagnostic(nil,
+          {
+            kind = 'full',
+            items = {
+              make_error('Pull Diagnostic', 4, 4, 4, 4),
+            }
+          },
+          {
+            params = {
+              textDocument = { uri = fake_uri },
+            },
+            uri = fake_uri,
+            client_id = client_id,
+          },
+          {}
+        )
+
+        return get_extmarks(diagnostic_bufnr, client_id)
+      ]],
+        expected_spacing
+      )
+      eq(2, #extmarks)
+      eq(expected_spacing, #extmarks[1][4].virt_text[1][1])
+    end)
+
+    it('clears diagnostics when client detaches', function()
+      exec_lua([[
+        vim.lsp.diagnostic.on_diagnostic(nil,
+          {
+            kind = 'full',
+            items = {
+              make_error('Pull Diagnostic', 4, 4, 4, 4),
+            }
+          },
+          {
+            params = {
+              textDocument = { uri = fake_uri },
+            },
+            uri = fake_uri,
+            client_id = client_id,
+          },
+          {}
+        )
+      ]])
+      local diags = exec_lua([[return vim.diagnostic.get(diagnostic_bufnr)]])
+      eq(1, #diags)
+
+      exec_lua([[ vim.lsp.stop_client(client_id) ]])
+
+      diags = exec_lua([[return vim.diagnostic.get(diagnostic_bufnr)]])
+      eq(0, #diags)
+    end)
+
+    it('keeps diagnostics when one client detaches and others still are attached', function()
+      exec_lua([[
+        client_id2 = vim.lsp.start({ name = 'dummy2', cmd = server.cmd })
+
+        vim.lsp.diagnostic.on_diagnostic(nil,
+          {
+            kind = 'full',
+            items = {
+              make_error('Pull Diagnostic', 4, 4, 4, 4),
+            }
+          },
+          {
+            params = {
+              textDocument = { uri = fake_uri },
+            },
+            uri = fake_uri,
+            client_id = client_id,
+          },
+          {}
+        )
+      ]])
+      local diags = exec_lua([[return vim.diagnostic.get(diagnostic_bufnr)]])
+      eq(1, #diags)
+
+      exec_lua([[ vim.lsp.stop_client(client_id2) ]])
+
+      diags = exec_lua([[return vim.diagnostic.get(diagnostic_bufnr)]])
+      eq(1, #diags)
+    end)
+  end)
 end)
diff --git a/test/functional/plugin/lsp/helpers.lua b/test/functional/plugin/lsp/helpers.lua
index caab174b4d..15e6a62781 100644
--- a/test/functional/plugin/lsp/helpers.lua
+++ b/test/functional/plugin/lsp/helpers.lua
@@ -13,6 +13,7 @@ function M.clear_notrace()
   -- solution: don't look too closely for dragons
   clear {env={
     NVIM_LUA_NOTRACK="1";
+    NVIM_APPNAME="nvim_lsp_test";
     VIMRUNTIME=os.getenv"VIMRUNTIME";
   }}
 end
@@ -85,6 +86,7 @@ local function fake_lsp_server_setup(test_name, timeout_ms, options, settings)
       cmd_env = {
         NVIM_LOG_FILE = fake_lsp_logfile;
         NVIM_LUA_NOTRACK = "1";
+        NVIM_APPNAME = "nvim_lsp_test";
       };
       cmd = {
         vim.v.progpath, '-l', fake_lsp_code, test_name, tostring(timeout),
@@ -97,7 +99,7 @@ local function fake_lsp_server_setup(test_name, timeout_ms, options, settings)
         end;
       });
       workspace_folders = {{
-          uri = 'file://' .. vim.loop.cwd(),
+          uri = 'file://' .. vim.uv.cwd(),
           name = 'test_folder',
       }};
       on_init = function(client, result)
diff --git a/test/functional/plugin/lsp/incremental_sync_spec.lua b/test/functional/plugin/lsp/incremental_sync_spec.lua
index 4985da9cd7..724b3efb97 100644
--- a/test/functional/plugin/lsp/incremental_sync_spec.lua
+++ b/test/functional/plugin/lsp/incremental_sync_spec.lua
@@ -21,7 +21,7 @@ before_each(function ()
     --   ["mac"] = '\r',
     -- }
 
-    -- local line_ending = format_line_ending[vim.api.nvim_buf_get_option(0, 'fileformat')]
+    -- local line_ending = format_line_ending[vim.api.nvim_get_option_value('fileformat', {})]
 
 
     function test_register(bufnr, id, offset_encoding, line_ending)
diff --git a/test/functional/plugin/lsp/inlay_hint_spec.lua b/test/functional/plugin/lsp/inlay_hint_spec.lua
new file mode 100644
index 0000000000..d0d55df72b
--- /dev/null
+++ b/test/functional/plugin/lsp/inlay_hint_spec.lua
@@ -0,0 +1,204 @@
+local helpers = require('test.functional.helpers')(after_each)
+local lsp_helpers = require('test.functional.plugin.lsp.helpers')
+local Screen = require('test.functional.ui.screen')
+
+local eq = helpers.eq
+local dedent = helpers.dedent
+local exec_lua = helpers.exec_lua
+local insert = helpers.insert
+
+local clear_notrace = lsp_helpers.clear_notrace
+local create_server_definition = lsp_helpers.create_server_definition
+
+local text = dedent([[
+auto add(int a, int b) { return a + b; }
+
+int main() {
+    int x = 1;
+    int y = 2;
+    return add(x,y);
+}
+}]])
+
+local response = [==[
+[
+{"kind":1,"paddingLeft":false,"label":"-> int","position":{"character":22,"line":0},"paddingRight":false},
+{"kind":2,"paddingLeft":false,"label":"a:","position":{"character":15,"line":5},"paddingRight":true},
+{"kind":2,"paddingLeft":false,"label":"b:","position":{"character":17,"line":5},"paddingRight":true}
+]
+]==]
+
+local grid_without_inlay_hints = [[
+  auto add(int a, int b) { return a + b; }          |
+                                                    |
+  int main() {                                      |
+      int x = 1;                                    |
+      int y = 2;                                    |
+      return add(x,y);                              |
+  }                                                 |
+  ^}                                                 |
+                                                    |
+]]
+
+local grid_with_inlay_hints =  [[
+  auto add(int a, int b)-> int { return a + b; }    |
+                                                    |
+  int main() {                                      |
+      int x = 1;                                    |
+      int y = 2;                                    |
+      return add(a: x,b: y);                        |
+  }                                                 |
+  ^}                                                 |
+                                                    |
+]]
+
+--- @type test.functional.ui.screen
+local screen
+before_each(function()
+  clear_notrace()
+  screen = Screen.new(50, 9)
+  screen:attach()
+
+  exec_lua(create_server_definition)
+  exec_lua([[
+    local response = ...
+    server = _create_server({
+      capabilities = {
+        inlayHintProvider = true,
+      },
+      handlers = {
+        ['textDocument/inlayHint'] = function()
+          return vim.json.decode(response)
+        end,
+      }
+    })
+
+    bufnr = vim.api.nvim_get_current_buf()
+    vim.api.nvim_win_set_buf(0, bufnr)
+
+    client_id = vim.lsp.start({ name = 'dummy', cmd = server.cmd })
+  ]], response)
+
+  insert(text)
+  exec_lua([[vim.lsp.inlay_hint.enable(bufnr)]])
+  screen:expect({ grid = grid_with_inlay_hints })
+end)
+
+after_each(function()
+  exec_lua("vim.api.nvim_exec_autocmds('VimLeavePre', { modeline = false })")
+end)
+
+describe('vim.lsp.inlay_hint', function()
+  it('clears inlay hints when sole client detaches', function()
+    exec_lua([[vim.lsp.stop_client(client_id)]])
+    screen:expect({ grid = grid_without_inlay_hints, unchanged = true })
+  end)
+
+  it('does not clear inlay hints when one of several clients detaches', function()
+    exec_lua([[
+      server2 = _create_server({
+        capabilities = {
+          inlayHintProvider = true,
+        },
+        handlers = {
+          ['textDocument/inlayHint'] = function()
+            return {}
+          end,
+        }
+      })
+      client2 = vim.lsp.start({ name = 'dummy2', cmd = server2.cmd })
+      vim.lsp.inlay_hint.enable(bufnr)
+    ]])
+
+    exec_lua([[ vim.lsp.stop_client(client2) ]])
+    screen:expect({ grid = grid_with_inlay_hints, unchanged = true })
+  end)
+
+  describe('enable()', function()
+    it('clears/applies inlay hints when passed false/true/nil', function()
+      exec_lua([[vim.lsp.inlay_hint.enable(bufnr, false)]])
+      screen:expect({ grid = grid_without_inlay_hints, unchanged = true })
+
+      exec_lua([[vim.lsp.inlay_hint.enable(bufnr, true)]])
+      screen:expect({ grid = grid_with_inlay_hints, unchanged = true })
+
+      exec_lua([[vim.lsp.inlay_hint.enable(bufnr, not vim.lsp.inlay_hint.is_enabled(bufnr))]])
+      screen:expect({ grid = grid_without_inlay_hints, unchanged = true })
+
+      exec_lua([[vim.lsp.inlay_hint.enable(bufnr)]])
+      screen:expect({ grid = grid_with_inlay_hints, unchanged = true })
+    end)
+  end)
+
+  describe('get()', function()
+    it('returns filtered inlay hints', function()
+      --- @type lsp.InlayHint[]