feat(lsp): implement workspace/didChangeWatchedFiles (#21293)

test/functional/lua/watch_spec.lua

@@ -0,0 +1,195 @@
+local helpers = require('test.functional.helpers')(after_each)
+local eq = helpers.eq
+local exec_lua = helpers.exec_lua
+local clear = helpers.clear
+local is_os = helpers.is_os
+local lfs = require('lfs')
+
+describe('vim._watch', function()
+  before_each(function()
+    clear()
+  end)
+
+  describe('watch', function()
+    it('detects file changes', function()
+      local root_dir = helpers.tmpname()
+      os.remove(root_dir)
+      lfs.mkdir(root_dir)
+
+      local result = exec_lua(
+        [[
+        local root_dir = ...
+
+        local events = {}
+
+        local expected_events = 0
+        local function wait_for_events()
+          assert(vim.wait(100, function() return #events == expected_events end), 'Timed out waiting for expected number of events. Current events seen so far: ' .. vim.inspect(events))
+        end
+
+        local stop = vim._watch.watch(root_dir, {}, function(path, change_type)
+          table.insert(events, { path = path, change_type = change_type })
+        end)
+
+        -- Only BSD seems to need some extra time for the watch to be ready to respond to events
+        if vim.fn.has('bsd') then
+          vim.wait(50)
+        end
+
+        local watched_path = root_dir .. '/file'
+        local watched, err = io.open(watched_path, 'w')
+        assert(not err, err)
+
+        expected_events = expected_events + 1
+        wait_for_events()
+
+        watched:close()
+        os.remove(watched_path)
+
+        expected_events = expected_events + 1
+        wait_for_events()
+
+        stop()
+        -- No events should come through anymore
+
+        local watched_path = root_dir .. '/file'
+        local watched, err = io.open(watched_path, 'w')
+        assert(not err, err)
+
+        vim.wait(50)
+
+        watched:close()
+        os.remove(watched_path)
+
+        vim.wait(50)
+
+        return events
+      ]],
+        root_dir
+      )
+
+      local expected = {
+        {
+          change_type = exec_lua([[return vim._watch.FileChangeType.Created]]),
+          path = root_dir .. '/file',
+        },
+        {
+          change_type = exec_lua([[return vim._watch.FileChangeType.Deleted]]),
+          path = root_dir .. '/file',
+        },
+      }
+
+      -- kqueue only reports events on the watched path itself, so creating a file within a
+      -- watched directory results in a "rename" libuv event on the directory.
+      if is_os('bsd') then
+        expected = {
+          {
+            change_type = exec_lua([[return vim._watch.FileChangeType.Created]]),
+            path = root_dir,
+          },
+          {
+            change_type = exec_lua([[return vim._watch.FileChangeType.Created]]),
+            path = root_dir,
+          },
+        }
+      end
+
+      eq(expected, result)
+    end)
+  end)
+
+  describe('poll', function()
+    it('detects file changes', function()
+      local root_dir = helpers.tmpname()
+      os.remove(root_dir)
+      lfs.mkdir(root_dir)
+
+      local result = exec_lua(
+        [[
+        local root_dir = ...
+
+        local events = {}
+
+        local poll_interval_ms = 1000
+        local poll_wait_ms = poll_interval_ms+200
+
+        local expected_events = 0
+        local function wait_for_events()
+          assert(vim.wait(poll_wait_ms, function() return #events == expected_events end), 'Timed out waiting for expected number of events. Current events seen so far: ' .. vim.inspect(events))
+        end
+
+        local stop = vim._watch.poll(root_dir, { interval = poll_interval_ms }, function(path, change_type)
+          table.insert(events, { path = path, change_type = change_type })
+        end)
+
+        -- polling generates Created events for the existing entries when it starts.
+        expected_events = expected_events + 1
+        wait_for_events()
+
+        local watched_path = root_dir .. '/file'
+        local watched, err = io.open(watched_path, 'w')
+        assert(not err, err)
+
+        expected_events = expected_events + 2
+        wait_for_events()
+
+        watched:close()
+        os.remove(watched_path)
+
+        expected_events = expected_events + 2
+        wait_for_events()
+
+        stop()
+        -- No events should come through anymore
+
+        local watched_path = root_dir .. '/file'
+        local watched, err = io.open(watched_path, 'w')
+        assert(not err, err)
+
+        vim.wait(poll_wait_ms)
+
+        watched:close()
+        os.remove(watched_path)
+
+        return events
+      ]],
+        root_dir
+      )
+
+      eq(5, #result)
+      eq({
+        change_type = exec_lua([[return vim._watch.FileChangeType.Created]]),
+        path = root_dir,
+      }, result[1])
+      eq({
+        change_type = exec_lua([[return vim._watch.FileChangeType.Created]]),
+        path = root_dir .. '/file',
+      }, result[2])
+      eq({
+        change_type = exec_lua([[return vim._watch.FileChangeType.Changed]]),
+        path = root_dir,
+      }, result[3])
+      -- The file delete and corresponding directory change events do not happen in any
+      -- particular order, so allow either
+      if result[4].path == root_dir then
+        eq({
+          change_type = exec_lua([[return vim._watch.FileChangeType.Changed]]),
+          path = root_dir,
+        }, result[4])
+        eq({
+          change_type = exec_lua([[return vim._watch.FileChangeType.Deleted]]),
+          path = root_dir .. '/file',
+        }, result[5])
+      else
+        eq({
+          change_type = exec_lua([[return vim._watch.FileChangeType.Deleted]]),
+          path = root_dir .. '/file',
+        }, result[4])
+        eq({
+          change_type = exec_lua([[return vim._watch.FileChangeType.Changed]]),
+          path = root_dir,
+        }, result[5])
+      end
+    end)
+  end)
+end)