WIP: Add readline util

.github/workflows/main.yml

@@ -214,7 +214,7 @@ jobs:
           retention-days: 1 # Minimum.
           path: |
             addons
-            !addons/godot-xterm
+            !addons/godot_xterm
  
 
   html5_export:
@@ -286,7 +286,7 @@ jobs:
         uses: actions/download-artifact@v2
         with:
           name: plugins
-          path: ./
+          path: ./addons
       - name: Run tests
         if: ${{ matrix.godot_version != 'v3.2-stable' }}
         shell: bash

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 [Unreleased]: https://github.com/lihop/godot-xterm/compare/v2.0.0...HEAD
+### Added
+- Basic readline utility that provides line editing capabilities similar to GNU Readline.
+
 ### Removed
 - TerminalSettings resource. Not currently used, and was showing up in every 'new resource' menu that is displayed after clicking on an empty Resource slot.
 

addons/godot_xterm/util/readline.gd

@@ -0,0 +1,108 @@
+# Copyright (c) 2021, Leroy Hopson (MIT License).
+tool
+extends Reference
+
+const KeyCodes = {
+	ESCAPE = "\u001b",
+	ENTER = "\r",
+	BACKSPACE = "\u0008",
+	UP_ARROW = "\u001b[A",
+	DOWN_ARROW = "\u001b[B",
+	LEFT_ARROW = "\u001b[D",
+	RIGHT_ARROW = "\u001b[C",
+}
+
+var terminal
+var _prompt: String
+var _cursor_pos_min: int
+var _cursor_pos: int
+var _line: String
+
+
+func _init(p_terminal) -> void:
+	terminal = p_terminal
+	assert(terminal.has_method("write"))
+	assert(terminal.has_signal("key_pressed"))
+	assert("cols" in terminal)
+	assert("rows" in terminal)
+
+
+func readline(prompt := "> ") -> String:
+	_prompt = prompt
+	_cursor_pos_min = prompt.length()
+	_cursor_pos = prompt.length()
+
+	terminal.write(_prompt)
+
+	var input = yield(terminal, "key_pressed")
+	while input[1].scancode != KEY_ENTER:
+		print(input[0])
+		match input[0]:
+			KeyCodes.BACKSPACE:
+				_backspace()
+			KeyCodes.UP_ARROW:
+				# TODO: History prev.
+				pass
+			KeyCodes.DOWN_ARROW:
+				# TODO: History next.
+				pass
+			KeyCodes.LEFT_ARROW, KeyCodes.RIGHT_ARROW:
+				# TODO: Implement Me!
+				pass
+			_:
+				terminal.write(input[0])
+				_line += input[0]
+				_cursor_pos += 1
+				if _cursor_pos > 0 and _cursor_pos % int(terminal.cols) == 0:
+					terminal.write("\u001bE")
+		input = yield(terminal, "key_pressed")
+
+	return _line
+
+
+func _backspace() -> void:
+	if _cursor_pos > _cursor_pos_min:
+		if _cursor_pos % int(terminal.cols) == 0:
+			terminal.write("\u001b[1A\u001b[%dC\u001b[K" % terminal.cols)
+		else:
+			terminal.write("\b \b")
+		_line = _line.substr(0, _cursor_pos - _cursor_pos_min - 1)
+		_cursor_pos -= 1
+
+
+func _refresh_line() -> void:
+	var num_rows := ceil(_cursor_pos / terminal.cols)
+	for _row in range(num_rows):
+		terminal.write("\r\u001b[2K\u001b[1A")
+	terminal.write("\r\u001b[1B%s%s" % [_prompt, _line])
+	_cursor_pos = _prompt.length()
+	_cursor_pos += _line.length()
+
+## TODO
+#func _add_history(line: String) -> void:
+#	_history.append(line)
+#
+#
+## TODO
+#func _load_history(filepath) -> int:
+#	var file := File.new()
+#	var err := file.open(filepath, File.READ)
+#	if err == OK:
+#		var line := file.get_line()
+#		while line != "":
+#			_history.append(line)
+#			line = file.get_line()
+#	file.close()
+#	return err
+#
+#
+## TODO
+#func _save_history(filepath) -> int:
+#	var file := File.new()
+#	var err := file.open(filepath, File.WRITE)
+#	if err == OK:
+#		for line in _history:
+#			assert(line is String)
+#			file.store_line(line)
+#	file.close()
+#	return err

examples/readline/readline.gd

@@ -0,0 +1,12 @@
+extends "res://addons/godot_xterm/terminal.gd"
+
+const Readline = preload("res://addons/godot_xterm/util/readline.gd")
+
+var rl: Readline
+
+
+func _ready():
+	rl = Readline.new(self)
+	while true:
+		var line: String = yield(rl.readline("Enter something (anything): "), "completed")
+		write("\r\nYou entered: %s\r\n" % line)

examples/readline/readline.tscn

@@ -0,0 +1,13 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://examples/readline/readline.gd" type="Script" id=1]
+
+[node name="Terminal" type="Control"]
+anchor_right = 1.0
+anchor_bottom = 1.0
+rect_pivot_offset = Vector2( -194.759, 935.803 )
+focus_mode = 2
+script = ExtResource( 1 )
+__meta__ = {
+"_edit_use_anchors_": false
+}

test/unit/readline.test.gd

@@ -0,0 +1,196 @@
+extends "res://addons/gut/test.gd"
+
+
+class TestReadline:
+	extends "res://addons/gut/test.gd"
+	const Readline = preload("res://addons/godot_xterm/util/readline.gd")
+	const Terminal = preload("res://addons/godot_xterm/terminal.gd")
+
+	var rl: Readline
+	var terminal: Terminal
+	var thread: Thread
+
+	func before_each():
+		terminal = Terminal.new()
+		add_child_autoqfree(terminal)
+		rl = Readline.new(terminal)
+		thread = Thread.new()
+
+	func after_each():
+		if thread.is_active():
+			thread.wait_to_finish()
+
+	func press_keys(keys):
+		yield(get_tree(), "idle_frame")
+		for key in keys:
+			terminal.call_deferred("emit_signal", "key_pressed", key[0], key[1])
+
+	func key(string: String) -> Array:
+		var event = InputEventKey.new()
+
+		if string.length() == 1:
+			event.unicode = ord(string)
+
+		match string:
+			"\r":
+				event.scancode = KEY_ENTER
+			"\b":
+				event.scancode = KEY_BACKSPACE
+
+		return [string, event]
+
+
+class TestBasic:
+	extends TestReadline
+
+	func test_immediate_return():
+		thread.start(self, "press_keys", [key("\r")])
+		var line = yield(rl.readline("hello> "), "completed")
+		assert_eq(line, "")
+
+	func test_basic_input():
+		thread.start(
+			self,
+			"press_keys",
+			[
+				key("t"),
+				key("e"),
+				key("s"),
+				key("t"),
+				key("\r"),
+			]
+		)
+		var line = yield(rl.readline("test> "), "completed")
+		assert_eq(line, "test")
+
+	func test_basic_input_no_prompt():
+		thread.start(
+			self,
+			"press_keys",
+			[
+				key("o"),
+				key("k"),
+				key("\r"),
+			]
+		)
+		var line = yield(rl.readline(), "completed")
+		assert_eq(line, "ok")
+
+	func test_basic_input_empty_prompt():
+		thread.start(
+			self,
+			"press_keys",
+			[
+				key("h"),
+				key("i"),
+				key("\r"),
+			]
+		)
+		var line = yield(rl.readline(""), "completed")
+		assert_eq(line, "hi")
+
+	func test_backspace_in_line():
+		thread.start(
+			self,
+			"press_keys",
+			[
+				key("a"),
+				key("b"),
+				key("c"),
+				key("\b"),
+				key("d"),
+				key("\r"),
+			]
+		)
+		var line = yield(rl.readline("> "), "completed")
+		assert_eq(line, "abd")
+
+	func test_backspace_to_prompt():
+		thread.start(
+			self,
+			"press_keys",
+			[
+				key("a"),
+				key("\b"),
+				key("\b"),
+				key("\b"),
+				key("\b"),
+				key("b"),
+				key("\r"),
+			]
+		)
+		var line = yield(rl.readline("aprompt> "), "completed")
+		var buffer = terminal.copy_all()
+		assert_eq(buffer.strip_edges(false, true), "aprompt>")
+		assert_eq(line, "b")
+
+	func test_multi_line():
+		var keys = []
+		for _i in range(terminal.cols * 3):
+			keys.append(key("a"))
+		keys.append(key("\r"))
+
+		thread.start(self, "press_keys", keys)
+		var line = yield(rl.readline("> "), "completed")
+		assert_eq(line, "a".repeat(terminal.cols * 3))
+
+	func test_backspace_multi_line():
+		var keys = []
+		for _i in range(terminal.cols):
+			keys.append(key("a"))
+		for _j in range(terminal.cols):
+			keys.append(key("b"))
+		for _k in range(terminal.cols + 5):
+			keys.append(key("\b"))
+		keys.append(key("f"))
+		keys.append(key("\r"))
+
+		thread.start(self, "press_keys", keys)
+		var line = yield(rl.readline("> "), "completed")
+		assert_eq(line, "a".repeat(terminal.cols - 5) + "f")
+		var buffer = terminal.copy_all()
+		assert(buffer.strip_edges(false, true), "> " + "a".repeat(terminal.cols - 5) + "f")
+
+#class TestHistory:
+#	extends TestReadline
+#
+#	func test_add_history():
+#		rl.history = ["1", "2", "3"]
+#		rl.add_history("New line")
+#		assert_eq(rl.history, ["1", "2", "3", "New line"])
+#
+#	func test_add_history_max_len():
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 3
+#		rl.add_history("New line")
+#		assert_eq(rl.history, ["2", "3", "New line"])
+#
+#	func test_add_history_0_max_len():
+#		rl.history = []
+#		rl.history_max_len = 0
+#		rl.add_history("New line")
+#		assert_eq(rl.history, [])
+#
+#	func test_equal_max_len():
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 3
+#		assert_eq(rl.history, ["1", "2", "3"])
+#
+#	func test_larger_max_len():
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 4
+#		assert_eq(rl.history, ["1", "2", "3"])
+#
+#	func test_smaller_max_len():
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 2
+#		assert_eq(rl.history, ["2", "3"])
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 1
+#		assert_eq(rl.history, ["3"])
+#		rl.history = ["1", "2", "3"]
+#		rl.history_max_len = 0
+#		assert_eq(rl.history, [])
+#		rl.history = ["1"]
+#		rl.history_max_len = 0
+#		assert_eq(rl.history, [])