api/lua: add on_detach to nvim_buf_attach

test/functional/lua/buffer_updates_spec.lua

@@ -0,0 +1,92 @@
+-- Test suite for testing interactions with API bindings
+local helpers = require('test.functional.helpers')(after_each)
+
+local command = helpers.command
+local meths = helpers.meths
+local clear = helpers.clear
+local eq = helpers.eq
+
+local origlines = {"original line 1",
+                   "original line 2",
+                   "original line 3",
+                   "original line 4",
+                   "original line 5",
+                   "original line 6"}
+
+describe('lua: buffer event callbacks', function()
+  before_each(function()
+    clear()
+    meths.execute_lua([[
+      local events = {}
+
+      function test_register(bufnr, id, changedtick)
+        local function callback(...)
+          table.insert(events, {id, ...})
+          if test_unreg == id then
+            return true
+          end
+        end
+        local opts = {on_lines=callback, on_detach=callback}
+        if changedtick then
+          opts.on_changedtick = callback
+        end
+        vim.api.nvim_buf_attach(bufnr, false, opts)
+      end
+
+      function get_events()
+        local ret_events = events
+        events = {}
+        return ret_events
+      end
+    ]], {})
+  end)
+
+  it('works', function()
+    meths.buf_set_lines(0, 0, -1, true, origlines)
+    meths.execute_lua("return test_register(...)", {0, "test1"})
+    local tick = meths.buf_get_changedtick(0)
+
+    command('normal! GyyggP')
+    tick = tick + 1
+    eq({{ "test1", "lines", 1, tick, 0, 0, 1 }},
+       meths.execute_lua("return get_events(...)", {}))
+
+    meths.buf_set_lines(0, 3, 5, true, {"changed line"})
+    tick = tick + 1
+    eq({{ "test1", "lines", 1, tick, 3, 5, 4 }},
+       meths.execute_lua("return get_events(...)", {}))
+
+    meths.execute_lua("return test_register(...)", {0, "test2", true})
+    tick = tick + 1
+    command('undo')
+
+    -- plugins can opt in to receive changedtick events, or choose
+    -- to only recieve actual changes.
+    eq({{ "test1", "lines", 1, tick, 3, 4, 5 },
+        { "test2", "lines", 1, tick, 3, 4, 5 },
+        { "test2", "changedtick", 1, tick+1 } },
+       meths.execute_lua("return get_events(...)", {}))
+    tick = tick + 1
+
+    -- simulate next callback returning true
+    meths.execute_lua("test_unreg = 'test1'", {})
+
+    meths.buf_set_lines(0, 6, 7, true, {"x1","x2","x3"})
+    tick = tick + 1
+
+    -- plugins can opt in to receive changedtick events, or choose
+    -- to only recieve actual changes.
+    eq({{ "test1", "lines", 1, tick, 6, 7, 9 },
+        { "test2", "lines", 1, tick, 6, 7, 9 }},
+       meths.execute_lua("return get_events(...)", {}))
+
+    meths.buf_set_lines(0, 1, 1, true, {"added"})
+    tick = tick + 1
+    eq({{ "test2", "lines", 1, tick, 1, 1, 2 }},
+       meths.execute_lua("return get_events(...)", {}))
+
+    command('bwipe!')
+    eq({{ "test2", "detach", 1 }},
+       meths.execute_lua("return get_events(...)", {}))
+  end)
+end)