functests: Add some tests

test/functional/lua/api_spec.lua

@@ -0,0 +1,36 @@
+-- Test suite for testing interactions with API bindings
+local helpers = require('test.functional.helpers')(after_each)
+
+local funcs = helpers.funcs
+local clear = helpers.clear
+local NIL = helpers.NIL
+local eq = helpers.eq
+
+before_each(clear)
+
+describe('luaeval(vim.api.…)', function()
+  describe('with channel_id and buffer handle', function()
+    describe('nvim_buf_get_lines', function()
+      it('works', function()
+        funcs.setline(1, {"abc", "def", "a\nb", "ttt"})
+        eq({{_TYPE={}, _VAL={'a\nb'}}},
+           funcs.luaeval('vim.api.nvim_buf_get_lines(1, 2, 3, false)'))
+      end)
+    end)
+    describe('nvim_buf_set_lines', function()
+      it('works', function()
+        funcs.setline(1, {"abc", "def", "a\nb", "ttt"})
+        eq(NIL, funcs.luaeval('vim.api.nvim_buf_set_lines(1, 1, 2, false, {"b\\0a"})'))
+        eq({'abc', {_TYPE={}, _VAL={'b\na'}}, {_TYPE={}, _VAL={'a\nb'}}, 'ttt'},
+           funcs.luaeval('vim.api.nvim_buf_get_lines(1, 0, 4, false)'))
+      end)
+    end)
+  end)
+  describe('with errors', function()
+    it('transforms API errors into lua errors', function()
+      funcs.setline(1, {"abc", "def", "a\nb", "ttt"})
+      eq({false, 'string cannot contain newlines'},
+         funcs.luaeval('{pcall(vim.api.nvim_buf_set_lines, 1, 1, 2, false, {"b\\na"})}'))
+    end)
+  end)
+end)