bpo-30495: IDLE: Modernize textview.py with docstrings and PEP8 names (#1839)

Patch by Cheryl Sabella.

3 files changed, 62 insertions, 42 deletions

diff --git a/Lib/idlelib/idle_test/test_help_about.py b/Lib/idlelib/idle_test/test_help_about.py
index b98405d..15d1b6b 100644
--- a/Lib/idlelib/idle_test/test_help_about.py
+++ b/Lib/idlelib/idle_test/test_help_about.py
@@ -45,10 +45,10 @@ class LiveDialogTest(unittest.TestCase):
             button.invoke()
             self.assertEqual(
                     printer._Printer__lines[0],
-                    dialog._current_textview.textView.get('1.0', '1.end'))
+                    dialog._current_textview.text.get('1.0', '1.end'))
             self.assertEqual(
                     printer._Printer__lines[1],
-                    dialog._current_textview.textView.get('2.0', '2.end'))
+                    dialog._current_textview.text.get('2.0', '2.end'))
             dialog._current_textview.destroy()
 
     def test_file_buttons(self):
@@ -64,10 +64,11 @@ class LiveDialogTest(unittest.TestCase):
             with open(fn) as f:
                 self.assertEqual(
                         f.readline().strip(),
-                        dialog._current_textview.textView.get('1.0', '1.end'))
+                        dialog._current_textview.text.get('1.0', '1.end'))
                 f.readline()
-                self.assertEqual(f.readline().strip(),
-                                 dialog._current_textview.textView.get('3.0', '3.end'))
+                self.assertEqual(
+                    f.readline().strip(),
+                    dialog._current_textview.text.get('3.0', '3.end'))
             dialog._current_textview.destroy()
 
 
diff --git a/Lib/idlelib/idle_test/test_textview.py b/Lib/idlelib/idle_test/test_textview.py
index 57b886a..7a2f7e4 100644
--- a/Lib/idlelib/idle_test/test_textview.py
+++ b/Lib/idlelib/idle_test/test_textview.py
@@ -41,7 +41,7 @@ class TV(tv.TextViewer):  # Used in TextViewTest.
 
 # Call wrapper class with mock wait_window.
 class TextViewTest(unittest.TestCase):
-    
+
     def setUp(self):
         TV.transient.__init__()
         TV.grab_set.__init__()
@@ -52,19 +52,19 @@ class TextViewTest(unittest.TestCase):
         self.assertTrue(TV.transient.called)
         self.assertTrue(TV.grab_set.called)
         self.assertTrue(TV.wait_window.called)
-        view.Ok()
+        view.ok()
 
     def test_init_nonmodal(self):
         view = TV(root, 'Title', 'test text', modal=False)
         self.assertFalse(TV.transient.called)
         self.assertFalse(TV.grab_set.called)
         self.assertFalse(TV.wait_window.called)
-        view.Ok()
+        view.ok()
 
     def test_ok(self):
         view = TV(root, 'Title', 'test text', modal=False)
         view.destroy = Func()
-        view.Ok()
+        view.ok()
         self.assertTrue(view.destroy.called)
         del view.destroy  # Unmask real function.
         view.destroy()
@@ -86,13 +86,13 @@ class ViewFunctionTest(unittest.TestCase):
     def test_view_text(self):
         view = tv.view_text(root, 'Title', 'test text', modal=False)
         self.assertIsInstance(view, tv.TextViewer)
-        view.Ok()
+        view.ok()
 
     def test_view_file(self):
         view = tv.view_file(root, 'Title', __file__, modal=False)
         self.assertIsInstance(view, tv.TextViewer)
-        self.assertIn('Test', view.textView.get('1.0', '1.end'))
-        view.Ok()
+        self.assertIn('Test', view.text.get('1.0', '1.end'))
+        view.ok()
 
     def test_bad_file(self):
         # Mock showerror will be used; view_file will return None.
@@ -131,7 +131,7 @@ class ButtonClickTest(unittest.TestCase):
 
         self.assertEqual(self.called, True)
         self.assertEqual(self.view.title(), 'TITLE_TEXT')
-        self.assertEqual(self.view.textView.get('1.0', '1.end'), 'COMMAND')
+        self.assertEqual(self.view.text.get('1.0', '1.end'), 'COMMAND')
 
     def test_view_file_bind_with_button(self):
         def _command():
@@ -144,10 +144,10 @@ class ButtonClickTest(unittest.TestCase):
         self.assertEqual(self.called, True)
         self.assertEqual(self.view.title(), 'TITLE_FILE')
         with open(__file__) as f:
-            self.assertEqual(self.view.textView.get('1.0', '1.end'),
+            self.assertEqual(self.view.text.get('1.0', '1.end'),
                              f.readline().strip())
             f.readline()
-            self.assertEqual(self.view.textView.get('3.0', '3.end'),
+            self.assertEqual(self.view.text.get('3.0', '3.end'),
                              f.readline().strip())
 
 
diff --git a/Lib/idlelib/textview.py b/Lib/idlelib/textview.py
index dc1a7bf..ab653a9 100644
--- a/Lib/idlelib/textview.py
+++ b/Lib/idlelib/textview.py
@@ -1,7 +1,9 @@
 """Simple text browser for IDLE
 
 """
-from tkinter import *
+from tkinter import Toplevel, Frame, Button, Text
+from tkinter import DISABLED, SUNKEN, VERTICAL, WORD
+from tkinter import RIGHT, LEFT, TOP, BOTTOM, BOTH, X, Y
 from tkinter.ttk import Scrollbar
 from tkinter.messagebox import showerror
 
@@ -16,6 +18,9 @@ class TextViewer(Toplevel):
         If modal is left True, users cannot interact with other windows
         until the textview window is closed.
 
+        parent - parent of this dialog
+        title - string which is title of popup dialog
+        text - text to display in dialog
         _htest - bool; change box location when running htest.
         _utest - bool; don't wait_window when running unittest.
         """
@@ -29,16 +34,16 @@ class TextViewer(Toplevel):
         self.bg = '#ffffff'
         self.fg = '#000000'
 
-        self.CreateWidgets()
+        self.create_widgets()
         self.title(title)
-        self.protocol("WM_DELETE_WINDOW", self.Ok)
+        self.protocol("WM_DELETE_WINDOW", self.ok)
         self.parent = parent
-        self.textView.focus_set()
+        self.text.focus_set()
         # Bind keys for closing this dialog.
-        self.bind('<Return>',self.Ok)
-        self.bind('<Escape>',self.Ok)
-        self.textView.insert(0.0, text)
-        self.textView.config(state=DISABLED)
+        self.bind('<Return>', self.ok)
+        self.bind('<Escape>', self.ok)
+        self.text.insert(0.0, text)
+        self.text.config(state=DISABLED)
 
         if modal:
             self.transient(parent)
@@ -46,34 +51,48 @@ class TextViewer(Toplevel):
             if not _utest:
                 self.wait_window()
 
-    def CreateWidgets(self):
+    def create_widgets(self):
         "Create Frame with Text (with vertical Scrollbar) and Button."
-        frameText = Frame(self, relief=SUNKEN, height=700)
-        frameButtons = Frame(self)
-        self.buttonOk = Button(frameButtons, text='Close',
-                               command=self.Ok, takefocus=FALSE)
-        self.scrollbarView = Scrollbar(frameText, orient=VERTICAL,
-                                       takefocus=FALSE)
-        self.textView = Text(frameText, wrap=WORD, highlightthickness=0,
+        frame = Frame(self, relief=SUNKEN, height=700)
+        frame_buttons = Frame(self)
+        self.button_ok = Button(frame_buttons, text='Close',
+                                command=self.ok, takefocus=False)
+        self.scrollbar = Scrollbar(frame, orient=VERTICAL, takefocus=False)
+        self.text = Text(frame, wrap=WORD, highlightthickness=0,
                              fg=self.fg, bg=self.bg)
-        self.scrollbarView.config(command=self.textView.yview)
-        self.textView.config(yscrollcommand=self.scrollbarView.set)
-        self.buttonOk.pack()
-        self.scrollbarView.pack(side=RIGHT,fill=Y)
-        self.textView.pack(side=LEFT,expand=TRUE,fill=BOTH)
-        frameButtons.pack(side=BOTTOM,fill=X)
-        frameText.pack(side=TOP,expand=TRUE,fill=BOTH)
-
-    def Ok(self, event=None):
+        self.scrollbar.config(command=self.text.yview)
+        self.text.config(yscrollcommand=self.scrollbar.set)
+        
+        self.button_ok.pack()
+        self.scrollbar.pack(side=RIGHT, fill=Y)
+        self.text.pack(side=LEFT, expand=True, fill=BOTH)
+        frame_buttons.pack(side=BOTTOM, fill=X)
+        frame.pack(side=TOP, expand=True, fill=BOTH)
+
+    def ok(self, event=None):
+        """Dismiss text viewer dialog."""
         self.destroy()
 
 
 def view_text(parent, title, text, modal=True, _utest=False):
-    "Display text in a TextViewer."
+    """Create TextViewer for given text.
+
+    parent - parent of this dialog
+    title - string which is the title of popup dialog
+    text - text to display in this dialog
+    modal - controls if users can interact with other windows while this
+            dialog is displayed
+    _utest - bool; controls wait_window on unittest
+    """
     return TextViewer(parent, title, text, modal, _utest=_utest)
 
+
 def view_file(parent, title, filename, encoding=None, modal=True, _utest=False):
-    "Display file in a TextViever or show error message."
+    """Create TextViewer for text in filename.
+
+    Return error message if file cannot be read.  Otherwise calls view_text
+    with contents of the file.
+    """
     try:
         with open(filename, 'r', encoding=encoding) as file:
             contents = file.read()