Code cleanup and added unit tests.

Author: orbitalquark

README.md

@@ -16,12 +16,13 @@ Select "Tools > Lua REPL" to open the REPL. Typing the Enter key on any line eva
 line, unless that line is a continuation line. In that case, when finished, select the lines
 to evaluate and type Enter to evaluate the entire chunk.
 
-Lines may be optionally prefixed with '=' (similar to the Lua prompt) to print a result.
+Tab completion is available, as is cycling through history with the `Ctrl+Up`/`Ctrl+Down`
+and `Ctrl+P` and `Ctrl+N` keys.
 
-<a id="lua_repl.complete_lua"></a>
-## `lua_repl.complete_lua`()
+**Note:** if the Language Server Protocol (LSP) module is enabled, any completions coming
+from that module are separate from this module's completions.
 
-Shows a set of Lua code completions for the current position.
+Lines may be optionally prefixed with '=' (similar to the Lua prompt) to print a result.
 
 <a id="lua_repl.cycle_history_next"></a>
 ## `lua_repl.cycle_history_next`()
@@ -48,7 +49,6 @@ Lua command history.
 It has a numeric `pos` field that indicates where in the history the user currently is.
 
 Fields:
-
 - `pos`: 
 
 <a id="lua_repl.keys"></a>

init.lua

@@ -15,6 +15,12 @@
 -- line, unless that line is a continuation line. In that case, when finished, select the lines
 -- to evaluate and type Enter to evaluate the entire chunk.
 --
+-- Tab completion is available, as is cycling through history with the `Ctrl+Up`/`Ctrl+Down`
+-- and `Ctrl+P` and `Ctrl+N` keys.
+--
+-- **Note:** if the Language Server Protocol (LSP) module is enabled, any completions coming
+-- from that module are separate from this module's completions.
+--
 -- Lines may be optionally prefixed with '=' (similar to the Lua prompt) to print a result.
 -- @module lua_repl
 local M = {}
@@ -87,8 +93,9 @@ function M.evaluate_repl()
 	buffer:set_save_point()
 end
 
---- Shows a set of Lua code completions for the current position.
-function M.complete_lua()
+-- Autocompleter function for the Lua REPL.
+-- @function _G.textadept.editing.autocompleters.lua_repl
+textadept.editing.autocompleters.lua_repl = function()
 	local line, pos = buffer:get_cur_line()
 	local symbol, op, part = line:sub(1, pos - 1):match('([%w_.]-)([%.:]?)([%w_]*)$')
 	local ok, result = pcall((load(string.format('return (%s)', symbol), nil, 't', env)))
@@ -109,17 +116,12 @@ function M.complete_lua()
 			end
 		end
 	end
-	table.sort(cmpls)
-	buffer.auto_c_separator, buffer.auto_c_order = string.byte(' '), buffer.ORDER_PRESORTED
-	buffer:auto_c_show(#part - 1, table.concat(cmpls, ' '))
+	return #part - 1, cmpls
 end
 
 --- Cycle backward through command history, taking into account commands with multiple lines.
 function M.cycle_history_prev()
-	if buffer:auto_c_active() then
-		buffer:line_up()
-		return
-	end
+	if buffer:auto_c_active() then return false end -- propagate
 	if M.history.pos <= 1 then return end
 	for _ in (M.history[M.history.pos] or ''):gmatch('\n') do
 		buffer:line_delete()
@@ -132,10 +134,7 @@ end
 
 --- Cycle forward through command history, taking into account commands with multiple lines.
 function M.cycle_history_next()
-	if buffer:auto_c_active() then
-		buffer:line_down()
-		return
-	end
+	if buffer:auto_c_active() then return false end -- propagate
 	if M.history.pos >= #M.history then return end
 	for _ in (M.history[M.history.pos] or ''):gmatch('\n') do
 		buffer:line_delete()
@@ -153,21 +152,30 @@ end
 
 M.keys = {
 	['\n'] = M.evaluate_repl, --
-	['ctrl+ '] = M.complete_lua, --
-	['ctrl+up'] = M.cycle_history_prev, --
-	['ctrl+down'] = M.cycle_history_next, --
-	['ctrl+p'] = M.cycle_history_prev, --
-	['ctrl+n'] = M.cycle_history_next
+	['\t'] = function() textadept.editing.autocomplete('lua_repl') end,
+	['ctrl+up'] = M.cycle_history_prev, ['ctrl+p'] = M.cycle_history_prev, --
+	['ctrl+down'] = M.cycle_history_next, ['ctrl+n'] = M.cycle_history_next
 }
 
+--- Returns whether or not a buffer is the REPL buffer.
+local function is_repl_buf(buf) return buf._type == _L['[Lua REPL]'] end
+
+--- Helper function for getting the REPL view.
+local function get_repl_view()
+	for _, view in ipairs(_VIEWS) do if is_repl_buf(view.buffer) then return view end end
+end
+--- Helper function for getting the REPL buffer.
+local function get_repl_buffer()
+	for _, buffer in ipairs(_BUFFERS) do if is_repl_buf(buffer) then return buffer end end
+end
+
 --- Register REPL keys.
 local function register_keys()
-	if not keys.lua[next(M.keys)] then
-		for key, f in pairs(M.keys) do
-			keys.lua[key] = function()
-				if buffer._type ~= '[Lua REPL]' then return false end -- propagate
-				f()
-			end
+	if keys.lua[next(M.keys)] then return end -- already registered
+	for key, f in pairs(M.keys) do
+		keys.lua[key] = function()
+			if buffer._type == '[Lua REPL]' then return f() end
+			return false -- propagate
 		end
 	end
 end
@@ -176,19 +184,7 @@ events.connect(events.RESET_AFTER, register_keys)
 --- Creates or switches to a Lua REPL.
 -- @param[opt=false] new Create a new REPL even if one already exists.
 function M.open(new)
-	local repl_view, repl_buf = nil, nil
-	for i = 1, #_VIEWS do
-		if _VIEWS[i].buffer._type == '[Lua REPL]' then
-			repl_view = _VIEWS[i]
-			break
-		end
-	end
-	for i = 1, #_BUFFERS do
-		if _BUFFERS[i]._type == '[Lua REPL]' then
-			repl_buf = _BUFFERS[i]
-			break
-		end
-	end
+	local repl_view, repl_buf = get_repl_view(), get_repl_buffer()
 	if new or not (repl_view or repl_buf) then
 		buffer.new()._type = '[Lua REPL]'
 		buffer:set_lexer('lua')

init_test.lua

@@ -0,0 +1,203 @@
+-- Copyright 2020-2025 Mitchell. See LICENSE.
+
+local lua_repl = require('lua_repl')
+
+test('lua_repl.open should open a REPL', function()
+	lua_repl.open()
+
+	test.assert_equal(buffer._type, _L['[Lua REPL]'])
+	test.assert_equal(buffer.lexer_language, 'lua')
+end)
+
+test('lua_repl.open should switch to an active REPL', function()
+	lua_repl.open()
+	view:goto_buffer(-1)
+
+	lua_repl.open()
+
+	test.assert_equal(buffer._type, _L['[Lua REPL]'])
+	test.assert_equal(#_BUFFERS, 2)
+end)
+
+test('lua_repl.open should switch to a REPL active in another view', function()
+	lua_repl.open()
+	view:split()
+	view:goto_buffer(-1)
+
+	lua_repl.open()
+
+	test.assert_equal(buffer._type, _L['[Lua REPL]'])
+	test.assert_equal(_VIEWS[view], 1)
+	test.assert_equal(_BUFFERS[_VIEWS[2].buffer], 1)
+end)
+
+local function get_previous_line() return buffer:get_line(buffer.line_count - 1):gsub('\r?\n', '') end
+local function get_current_line() return buffer:get_line(buffer.line_count) end
+
+test('lua_repl.open should always open a new REPL if told to do so', function()
+	lua_repl.open()
+	lua_repl.open(true)
+
+	test.assert_equal(#_BUFFERS, 3)
+end)
+
+test('Enter should evaluate the current line', function()
+	lua_repl.open()
+
+	test.type('1+2\n')
+
+	test.assert_equal(get_previous_line(), '--> 3')
+end)
+
+test('Enter should evaluate selected lines', function()
+	lua_repl.open()
+
+	test.type('1+\n')
+	test.type('2')
+	buffer:line_up_extend()
+	test.type('\n')
+
+	test.assert_equal(get_previous_line(), '--> 3')
+end)
+
+test('lua_repl.evaluate_repl should pretty-print tables', function()
+	lua_repl.open()
+
+	test.type('{1,2,3}\n')
+
+	test.assert_equal(get_previous_line(), '--> {1 = 1, 2 = 2, 3 = 3}')
+end)
+
+test('lua_repl.evaluate_repl should allow wrapping pretty-printed tables', function()
+	lua_repl.open()
+	local _<close> = test.mock(view, 'edge_column', 80)
+
+	test.type('buffer\n')
+
+	test.assert_equal(get_previous_line(), '--> }') -- result over multiple lines
+end)
+
+test('lua_repl.evaluate_repl should use its own print function', function()
+	lua_repl.open()
+
+	test.type('print(1,2,3)\n')
+
+	test.assert_equal(get_previous_line(), '--> 1\t2\t3')
+end)
+
+test('Tab should show completions', function()
+	lua_repl.open()
+	buffer:add_text('string.') -- avoid triggering LSP
+	local auto_c_show = test.stub()
+	local _<close> = test.mock(buffer, 'auto_c_show', auto_c_show)
+
+	test.type('\t')
+
+	test.assert_equal(auto_c_show.called, true)
+	test.assert_contains(auto_c_show.args[3], 'byte')
+end)
+
+test('Tab completions should include methods', function()
+	lua_repl.open()
+	buffer:add_text('buffer:get') -- avoid triggering LSP
+	local auto_c_show = test.stub()
+	local _<close> = test.mock(buffer, 'auto_c_show', auto_c_show)
+
+	test.type('\t')
+
+	test.assert_equal(auto_c_show.called, true)
+	test.assert_contains(auto_c_show.args[3], 'get_cur_line')
+end)
+
+test('ctrl+p should cycle backwards through history', function()
+	lua_repl.open()
+	test.type('1+2\n')
+
+	test.type('{1,2,3}')
+	test.type('ctrl+p')
+
+	test.assert_equal(get_current_line(), '1+2')
+end)
+
+test('ctrl+p history should support multi-line input', function()
+	lua_repl.open()
+	test.type('1+\n')
+	test.type('2')
+	buffer:line_up_extend()
+	test.type('\n')
+
+	test.type('ctrl+p')
+
+	test.assert_equal(get_previous_line(), '1+')
+	test.assert_equal(get_current_line(), '2')
+end)
+
+test('ctrl+p should stop cycling when there is no prior history', function()
+	lua_repl.open()
+	test.type('1+2\n')
+	test.type('ctrl+p')
+
+	test.type('ctrl+p')
+
+	test.assert_equal(get_current_line(), '1+2')
+end)
+
+test('ctrl+n should cycle forward through history', function()
+	lua_repl.open()
+	test.type('1+2\n')
+	test.type('{1,2,3}\n')
+	test.type('ctrl+p')
+	test.type('ctrl+p')
+
+	test.type('ctrl+n')
+
+	test.assert_equal(get_current_line(), '{1,2,3}')
+end)
+
+test('ctrl+n history should support multi-line input', function()
+	lua_repl.open()
+	test.type('1+\n')
+	test.type('2')
+	buffer:line_up_extend()
+	test.type('\n')
+	test.type('{1,2,3}\n')
+	test.type('ctrl+p')
+	test.type('ctrl+p')
+
+	test.type('ctrl+n')
+
+	test.assert_equal(get_previous_line(), '--> {1 = 1, 2 = 2, 3 = 3}')
+	test.assert_equal(get_current_line(), '{1,2,3}')
+end)
+
+test('ctrl+n should stop cycling when there is no more history', function()
+	lua_repl.open()
+	test.type('1+2\n')
+	test.type('{1,2,3}\n')
+	test.type('ctrl+p')
+	test.type('ctrl+p')
+	test.type('ctrl+n')
+
+	test.type('ctrl+n')
+
+	test.assert_equal(get_current_line(), '{1,2,3}')
+end)
+
+test('lua_repl functionality should survive a reset #skip', function()
+	lua_repl.open()
+
+	reset()
+	test.type('1+2')
+
+	test.assert_equal(get_previous_line(), '--> 3')
+end)
+
+-- Coverage tests.
+
+test('Enter should not do anything special in a Lua buffer', function()
+	buffer:set_lexer('lua')
+
+	test.type('\n')
+
+	test.assert_equal(buffer.line_count, 2)
+end)