fix(vim.opt): Add basic error handling

runtime/lua/vim/_meta.lua

@@ -311,6 +311,28 @@ local get_option_type = function(name, info)
 end
 
 
+-- Check whether the OptionTypes is allowed for vim.opt
+-- If it does not match, throw an error which indicates which option causes the error.
+local function assert_valid_value(name, value, types)
+  local type_of_value = type(value)
+  for _, valid_type in ipairs(types) do
+    if valid_type == type_of_value then
+      return
+    end
+  end
+
+  error(string.format("Invalid option type '%s' for '%s', should be %s", type_of_value, name, table.concat(types, " or ")))
+end
+
+local valid_types = {
+  [OptionTypes.BOOLEAN] = { "boolean" },
+  [OptionTypes.NUMBER]  = { "number" },
+  [OptionTypes.STRING]  = { "string" },
+  [OptionTypes.SET]     = { "string", "table" },
+  [OptionTypes.ARRAY]   = { "string", "table" },
+  [OptionTypes.MAP]     = { "string", "table" },
+}
+
 --- Convert a lua value to a vimoption_T value
 local convert_value_to_vim = (function()
   -- Map of functions to take a Lua style value and convert to vimoption_T style value.
@@ -340,7 +362,6 @@ local convert_value_to_vim = (function()
 
     [OptionTypes.MAP] = function(_, value)
       if type(value) == "string" then return value end
-      if type(value) == "function" then error(debug.traceback("asdf")) end
 
       local result = {}
       for opt_key, opt_value in pairs(value) do
@@ -353,7 +374,10 @@ local convert_value_to_vim = (function()
   }
 
   return function(name, info, value)
-    return to_vim_value[get_option_type(name, info)](info, value)
+    local option_type = get_option_type(name, info)
+    assert_valid_value(name, value, valid_types[option_type])
+
+    return to_vim_value[option_type](info, value)
   end
 end)()
 

test/functional/lua/vim_spec.lua

@@ -1592,6 +1592,128 @@ describe('lua stdlib', function()
 
       eq(wildmode, 'full,list,full')
     end)
+
+    describe('option types', function()
+      it('should allow to set option with numeric value', function()
+        eq(4, exec_lua [[
+          vim.opt.tabstop = 4
+          return vim.bo.tabstop
+        ]])
+
+        matches("Invalid option type 'string' for 'tabstop'", pcall_err(exec_lua, [[
+          vim.opt.tabstop = '4'
+        ]]))
+        matches("Invalid option type 'boolean' for 'tabstop'", pcall_err(exec_lua, [[
+          vim.opt.tabstop = true
+        ]]))
+        matches("Invalid option type 'table' for 'tabstop'", pcall_err(exec_lua, [[
+          vim.opt.tabstop = {4, 2}
+        ]]))
+        matches("Invalid option type 'function' for 'tabstop'", pcall_err(exec_lua, [[
+          vim.opt.tabstop = function()
+            return 4
+          end
+        ]]))
+      end)
+
+      it('should allow to set option with boolean value', function()
+        eq(true, exec_lua [[
+          vim.opt.undofile = true
+          return vim.bo.undofile
+        ]])
+
+        matches("Invalid option type 'number' for 'undofile'", pcall_err(exec_lua, [[
+          vim.opt.undofile = 0
+        ]]))
+        matches("Invalid option type 'table' for 'undofile'", pcall_err(exec_lua, [[
+          vim.opt.undofile = {true}
+        ]]))
+        matches("Invalid option type 'string' for 'undofile'", pcall_err(exec_lua, [[
+          vim.opt.undofile = 'true'
+        ]]))
+        matches("Invalid option type 'function' for 'undofile'", pcall_err(exec_lua, [[
+          vim.opt.undofile = function()
+            return true
+          end
+        ]]))
+      end)
+
+      it('should allow to set option with array or string value', function()
+        eq('indent,eol,start', exec_lua [[
+          vim.opt.backspace = {'indent','eol','start'}
+          return vim.go.backspace
+        ]])
+        eq('indent,eol,start', exec_lua [[
+          vim.opt.backspace = 'indent,eol,start'
+          return vim.go.backspace
+        ]])
+
+        matches("Invalid option type 'boolean' for 'backspace'", pcall_err(exec_lua, [[
+          vim.opt.backspace = true
+        ]]))
+        matches("Invalid option type 'number' for 'backspace'", pcall_err(exec_lua, [[
+          vim.opt.backspace = 2
+        ]]))
+        matches("Invalid option type 'function' for 'backspace'", pcall_err(exec_lua, [[
+          vim.opt.backspace = function()
+            return 'indent,eol,start'
+          end
+        ]]))
+      end)
+
+      it('should allow set option with map or string value', function()
+        eq("eol:~,space:.", exec_lua [[
+          vim.opt.listchars = {
+            eol = "~",
+            space = ".",
+          }
+          return vim.o.listchars
+        ]])
+        eq("eol:~,space:.,tab:>~", exec_lua [[
+          vim.opt.listchars = "eol:~,space:.,tab:>~"
+          return vim.o.listchars
+        ]])
+
+        matches("Invalid option type 'boolean' for 'listchars'", pcall_err(exec_lua, [[
+          vim.opt.listchars = true
+        ]]))
+        matches("Invalid option type 'number' for 'listchars'", pcall_err(exec_lua, [[
+          vim.opt.listchars = 2
+        ]]))
+        matches("Invalid option type 'function' for 'listchars'", pcall_err(exec_lua, [[
+          vim.opt.listchars = function()
+            return "eol:~,space:.,tab:>~"
+          end
+        ]]))
+      end)
+
+      it('should allow set option with set or string value', function()
+        local ww = exec_lua [[
+          vim.opt.whichwrap = {
+            b = true,
+            s = 1,
+          }
+          return vim.go.whichwrap
+        ]]
+        eq(true, ww == "bs" or ww == "sb")
+        eq("b,s,<,>,[,]", exec_lua [[
+          vim.opt.whichwrap = "b,s,<,>,[,]"
+          return vim.go.whichwrap
+        ]])
+
+        matches("Invalid option type 'boolean' for 'whichwrap'", pcall_err(exec_lua, [[
+          vim.opt.whichwrap = true
+        ]]))
+        matches("Invalid option type 'number' for 'whichwrap'", pcall_err(exec_lua, [[
+          vim.opt.whichwrap = 2
+        ]]))
+        matches("Invalid option type 'function' for 'whichwrap'", pcall_err(exec_lua, [[
+          vim.opt.whichwrap = function()
+            return "b,s,<,>,[,]"
+          end
+        ]]))
+      end)
+    end)
   end) -- vim.opt
 
   it('vim.cmd', function()