bpo-17535: IDLE editor line numbers

Doc/library/idle.rst

@@ -291,6 +291,10 @@ Zoom/Restore Height
    defaults to 40 lines by 80 chars unless changed on the General tab of the
    Configure IDLE dialog.
 
+Line Numbers (Editor Window only)
+   Open a column to the left of the edit window which shows the linenumber
+   of each line of text.
+
 Window menu (Shell and Editor)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

Lib/idlelib/config-extensions.def

@@ -17,6 +17,16 @@ style= expression
 flash-delay= 500
 bell= True
 
+# [LineNumber]
+# enable=1
+# enable_editor=1
+# # Should LineNumbering be visible on EditorWindow startup?
+# visible=0
+# bgcolor=Gray
+# fgcolor=Black
+# [LineNumber_bindings]
+# toggle-line-numbers=
+
 # IDLE reads several config files to determine user preferences.  This
 # file is the default configuration file for IDLE extensions settings.
 #

Lib/idlelib/config-highlight.def

@@ -22,6 +22,10 @@ hit-foreground= #ffffff
 hit-background= #000000
 error-foreground= #000000
 error-background= #ff7777
+context-foreground= #000000
+context-background= lightgray
+linenumber-foreground= gray
+linenumber-background= #ffffff
 #cursor (only foreground can be set, restart IDLE)
 cursor-foreground= black
 #shell window
@@ -31,8 +35,6 @@ stderr-foreground= red
 stderr-background= #ffffff
 console-foreground= #770000
 console-background= #ffffff
-context-foreground= #000000
-context-background= lightgray
 
 [IDLE New]
 normal-foreground= #000000
@@ -55,6 +57,10 @@ hit-foreground= #ffffff
 hit-background= #000000
 error-foreground= #000000
 error-background= #ff7777
+context-foreground= #000000
+context-background= lightgray
+linenumber-foreground= gray
+linenumber-background= #ffffff
 #cursor (only foreground can be set, restart IDLE)
 cursor-foreground= black
 #shell window
@@ -64,8 +70,6 @@ stderr-foreground= red
 stderr-background= #ffffff
 console-foreground= #770000
 console-background= #ffffff
-context-foreground= #000000
-context-background= lightgray
 
 [IDLE Dark]
 comment-foreground = #dd0000
@@ -97,3 +101,5 @@ comment-background = #002240
 break-foreground = #FFFFFF
 context-foreground= #ffffff
 context-background= #454545
+linenumber-foreground= gray
+linenumber-background= #002240

Lib/idlelib/config.py

@@ -336,6 +336,10 @@ def GetThemeDict(self, type, themeName):
                 'hit-background':'#000000',
                 'error-foreground':'#ffffff',
                 'error-background':'#000000',
+                'context-foreground':'#000000',
+                'context-background':'#ffffff',
+                'linenumber-foreground':'#000000',
+                'linenumber-background':'#ffffff',
                 #cursor (only foreground can be set)
                 'cursor-foreground':'#000000',
                 #shell window
@@ -345,8 +349,6 @@ def GetThemeDict(self, type, themeName):
                 'stderr-background':'#ffffff',
                 'console-foreground':'#000000',
                 'console-background':'#ffffff',
-                'context-foreground':'#000000',
-                'context-background':'#ffffff',
                 }
         for element in theme:
             if not cfgParser.has_option(themeName, element):

Lib/idlelib/configdialog.py

@@ -817,6 +817,7 @@ def create_page_highlight(self):
             'Shell Error Text': ('error', '12'),
             'Shell Stdout Text': ('stdout', '13'),
             'Shell Stderr Text': ('stderr', '14'),
+            'Line Number': ('linenumber', '16'),
             }
         self.builtin_name = tracers.add(
                 StringVar(self), self.var_changed_builtin_name)
@@ -864,6 +865,11 @@ def create_page_highlight(self):
             ('stderr', 'stderr'), ('\n\n', 'normal'))
         for texttag in text_and_tags:
             text.insert(END, texttag[0], texttag[1])
+        n_lines = len(text.get('1.0', END).splitlines())
+        for lineno in range(1, n_lines + 1):
+            text.insert(f'{lineno}.0',
+                        f'{lineno:{len(str(n_lines))}d} ',
+                        'linenumber')
         for element in self.theme_elements:
             def tem(event, elem=element):
                 # event.widget.winfo_top_level().highlight_target.set(elem)

Lib/idlelib/editor.py

@@ -54,6 +54,7 @@ class EditorWindow(object):
     from idlelib.calltip import Calltip
     from idlelib.codecontext import CodeContext
     from idlelib.paragraph import FormatParagraph
+    from idlelib.linenumbers import LineNumbers
     from idlelib.parenmatch import ParenMatch
     from idlelib.rstrip import Rstrip
     from idlelib.squeezer import Squeezer
@@ -62,6 +63,9 @@ class EditorWindow(object):
     filesystemencoding = sys.getfilesystemencoding()  # for file names
     help_url = None
 
+    allow_code_context = True
+    allow_line_numbers = True
+
     def __init__(self, flist=None, filename=None, key=None, root=None):
         # Delay import: runscript imports pyshell imports EditorWindow.
         from idlelib.runscript import ScriptBinding
@@ -247,6 +251,7 @@ def __init__(self, flist=None, filename=None, key=None, root=None):
         self.good_load = False
         self.set_indentation_params(False)
         self.color = None # initialized below in self.ResetColorizer
+        self.line_numbers = None # optionally initialized later below
         if filename:
             if os.path.exists(filename) and not os.path.isdir(filename):
                 if io.loadfile(filename):
@@ -311,8 +316,19 @@ def __init__(self, flist=None, filename=None, key=None, root=None):
         text.bind("<<refresh-calltip>>", ctip.refresh_calltip_event)
         text.bind("<<force-open-calltip>>", ctip.force_open_calltip_event)
         text.bind("<<zoom-height>>", self.ZoomHeight(self).zoom_height_event)
-        text.bind("<<toggle-code-context>>",
-                  self.CodeContext(self).toggle_code_context_event)
+        if self.allow_code_context:
+            code_context = self.CodeContext(self)
+            text.bind("<<toggle-code-context>>",
+                      code_context.toggle_code_context_event)
+        else:
+            self.update_menu_state('options', '*Code Context', 'disabled')
+        if self.allow_line_numbers:
+            self.line_numbers = self.LineNumbers(self)
+            text.bind("<<toggle-line-numbers>>",
+                      self.line_numbers.toggle_line_numbers_event)
+            pass
+        else:
+            self.update_menu_state('options', '*Line Numbers', 'disabled')
 
     def _filename_to_unicode(self, filename):
         """Return filename as BMP unicode so displayable in Tk."""
@@ -771,6 +787,8 @@ def ResetColorizer(self):
         self._rmcolorizer()
         self._addcolorizer()
         EditorWindow.color_config(self.text)
+        if self.line_numbers is not None:
+            self.line_numbers.update_sidebar_text_font()
 
     IDENTCHARS = string.ascii_letters + string.digits + "_"
 
@@ -790,6 +808,8 @@ def ResetFont(self):
         # Called from configdialog.py
 
         self.text['font'] = idleConf.GetFont(self.root, 'main','EditorWindow')
+        if self.line_numbers is not None:
+            self.line_numbers.update_sidebar_text_font()
 
     def RemoveKeybindings(self):
         "Remove the keybindings before they are changed."

Lib/idlelib/idle_test/test_linenumbers.py

@@ -0,0 +1,197 @@
+"""Unittest for idlelib.LineNumber"""
+from itertools import chain
+import unittest
+from test.support import requires
+import tkinter as tk
+
+from idlelib.delegator import Delegator
+from idlelib.percolator import Percolator
+from idlelib.linenumbers import LineNumbers
+
+
+class Dummy_editwin:
+    def __init__(self, text):
+        self.text = text
+        self.text_frame = self.text.master
+        self.per = Percolator(text)
+        self.undo = Delegator()
+        self.per.insertfilter(self.undo)
+
+    def setvar(self, name, value):
+        pass
+
+
+class LineNumberTest(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        requires('gui')
+        cls.root = tk.Tk()
+        cls.text = tk.Text(cls.root)
+        cls.editwin = Dummy_editwin(cls.text)
+        cls.editwin.vbar = tk.Scrollbar(cls.root)
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.editwin.per.close()
+        cls.text.destroy()
+        cls.root.destroy()
+        del cls.text, cls.editwin, cls.root
+
+    def setUp(self):
+        self.linenumber = LineNumbers(self.editwin)
+
+    def tearDown(self):
+        self.text.delete('1.0', 'end')
+
+    def assert_state_disabled(self):
+        state = self.linenumber.sidebar_text.config()['state']
+        self.assertEqual(state[-1], tk.DISABLED)
+
+    def get_sidebar_text_contents(self):
+        return self.linenumber.sidebar_text.get('1.0', tk.END)
+
+    def assert_sidebar_n_lines(self, n_lines):
+        expected = '\n'.join(chain(map(str, range(1, n_lines + 1)), ['']))
+        self.assertEqual(self.get_sidebar_text_contents(), expected)
+
+    def assert_text_equals(self, expected):
+        return self.assertEqual(self.text.get('1.0', 'end'), expected)
+
+    def test_init_empty(self):
+        self.assert_sidebar_n_lines(1)
+
+    def test_init_not_empty(self):
+        self.text.insert('insert', 'foo bar\n'*3)
+        self.assert_text_equals('foo bar\n'*3 + '\n')
+        self.assert_sidebar_n_lines(4)
+
+    def test_toggle_linenumbering(self):
+        self.assertEqual(self.linenumber.side, tk.LEFT)
+        self.linenumber.toggle_line_numbers_event(None)
+        self.assertEqual(self.linenumber.side, None)
+        self.linenumber.toggle_line_numbers_event(None)
+        self.assertEqual(self.linenumber.side, tk.LEFT)
+
+    def test_insert(self):
+        self.text.insert('insert', 'foobar')
+        self.assert_text_equals('foobar\n')
+        self.assert_sidebar_n_lines(1)
+        self.assert_state_disabled()
+
+        self.text.insert('insert', '\nfoo')
+        self.assert_text_equals('foobar\nfoo\n')
+        self.assert_sidebar_n_lines(2)
+        self.assert_state_disabled()
+
+        self.text.insert('insert', 'hello\n'*2)
+        self.assert_text_equals('foobar\nfoohello\nhello\n\n')
+        self.assert_sidebar_n_lines(4)
+        self.assert_state_disabled()
+
+        self.text.insert('insert', '\nworld')
+        self.assert_text_equals('foobar\nfoohello\nhello\n\nworld\n')
+        self.assert_sidebar_n_lines(5)
+        self.assert_state_disabled()
+
+    def test_delete(self):
+        self.text.insert('insert', 'foobar')
+        self.assert_text_equals('foobar\n')
+        self.text.delete('1.1', '1.3')
+        self.assert_text_equals('fbar\n')
+        self.assert_sidebar_n_lines(1)
+        self.assert_state_disabled()
+
+        self.text.insert('insert', 'foo\n'*2)
+        self.assert_text_equals('fbarfoo\nfoo\n\n')
+        self.assert_sidebar_n_lines(3)
+        self.assert_state_disabled()
+
+        # note: deleting up to "2.end" doesn't delete the final newline
+        self.text.delete('2.0', '2.end')
+        self.assert_text_equals('fbarfoo\n\n\n')
+        self.assert_sidebar_n_lines(3)
+        self.assert_state_disabled()
+
+        self.text.delete('1.3', 'end')
+        self.assert_text_equals('fba\n')
+        self.assert_sidebar_n_lines(1)
+        self.assert_state_disabled()
+
+        # note: Text widgets always keep a single '\n' character at the end
+        self.text.delete('1.0', 'end')
+        self.assert_text_equals('\n')
+        self.assert_sidebar_n_lines(1)
+        self.assert_state_disabled()
+
+    def test_sidebar_text_width(self):
+        """
+        Test that linenumber text widget is always at the minimum
+        width
+        """
+        def get_width():
+            return self.linenumber.sidebar_text.config()['width'][-1]
+
+        self.assert_sidebar_n_lines(1)
+        self.assertEqual(get_width(), 1)
+
+        self.text.insert('insert', 'foo')
+        self.assert_sidebar_n_lines(1)
+        self.assertEqual(get_width(), 1)
+
+        self.text.insert('insert', 'foo\n'*8)
+        self.assert_sidebar_n_lines(9)
+        self.assertEqual(get_width(), 1)
+
+        self.text.insert('insert', 'foo\n')
+        self.assert_sidebar_n_lines(10)
+        self.assertEqual(get_width(), 2)
+
+        self.text.insert('insert', 'foo\n')
+        self.assert_sidebar_n_lines(11)
+        self.assertEqual(get_width(), 2)
+
+        self.text.delete('insert -1l linestart', 'insert linestart')
+        self.assert_sidebar_n_lines(10)
+        self.assertEqual(get_width(), 2)
+
+        self.text.delete('insert -1l linestart', 'insert linestart')
+        self.assert_sidebar_n_lines(9)
+        self.assertEqual(get_width(), 1)
+
+        self.text.insert('insert', 'foo\n'*90)
+        self.assert_sidebar_n_lines(99)
+        self.assertEqual(get_width(), 2)
+
+        self.text.insert('insert', 'foo\n')
+        self.assert_sidebar_n_lines(100)
+        self.assertEqual(get_width(), 3)
+
+        self.text.insert('insert', 'foo\n')
+        self.assert_sidebar_n_lines(101)
+        self.assertEqual(get_width(), 3)
+
+        self.text.delete('insert -1l linestart', 'insert linestart')
+        self.assert_sidebar_n_lines(100)
+        self.assertEqual(get_width(), 3)
+
+        self.text.delete('insert -1l linestart', 'insert linestart')
+        self.assert_sidebar_n_lines(99)
+        self.assertEqual(get_width(), 2)
+
+        self.text.delete('50.0 -1c', 'end -1c')
+        self.assert_sidebar_n_lines(49)
+        self.assertEqual(get_width(), 2)
+
+        self.text.delete('5.0 -1c', 'end -1c')
+        self.assert_sidebar_n_lines(4)
+        self.assertEqual(get_width(), 1)
+
+        # note: Text widgets always keep a single '\n' character at the end
+        self.text.delete('1.0', 'end -1c')
+        self.assert_sidebar_n_lines(1)
+        self.assertEqual(get_width(), 1)
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)