bpo-1529353: IDLE: squeeze large output in the shell (GH-7626)

1 files changed, 52 insertions, 16 deletions

diff --git a/Lib/idlelib/textview.py b/Lib/idlelib/textview.py
index 464e6ac..4867a80 100644
--- a/Lib/idlelib/textview.py
+++ b/Lib/idlelib/textview.py
@@ -1,17 +1,37 @@
 """Simple text browser for IDLE
 
 """
-from tkinter import Toplevel, Text
+from tkinter import Toplevel, Text, TclError,\
+    HORIZONTAL, VERTICAL, N, S, E, W
 from tkinter.ttk import Frame, Scrollbar, Button
 from tkinter.messagebox import showerror
 
 from idlelib.colorizer import color_config
 
 
+class AutoHiddenScrollbar(Scrollbar):
+    """A scrollbar that is automatically hidden when not needed.
+
+    Only the grid geometry manager is supported.
+    """
+    def set(self, lo, hi):
+        if float(lo) > 0.0 or float(hi) < 1.0:
+            self.grid()
+        else:
+            self.grid_remove()
+        super().set(lo, hi)
+
+    def pack(self, **kwargs):
+        raise TclError(f'{self.__class__.__name__} does not support "pack"')
+
+    def place(self, **kwargs):
+        raise TclError(f'{self.__class__.__name__} does not support "place"')
+
+
 class TextFrame(Frame):
     "Display text with scrollbar."
 
-    def __init__(self, parent, rawtext):
+    def __init__(self, parent, rawtext, wrap='word'):
         """Create a frame for Textview.
 
         parent - parent widget for this frame
@@ -21,27 +41,39 @@ class TextFrame(Frame):
         self['relief'] = 'sunken'
         self['height'] = 700
 
-        self.text = text = Text(self, wrap='word', highlightthickness=0)
+        self.text = text = Text(self, wrap=wrap, highlightthickness=0)
         color_config(text)
-        self.scroll = scroll = Scrollbar(self, orient='vertical',
-                                         takefocus=False, command=text.yview)
-        text['yscrollcommand'] = scroll.set
+        text.grid(row=0, column=0, sticky=N+S+E+W)
+        self.grid_rowconfigure(0, weight=1)
+        self.grid_columnconfigure(0, weight=1)
         text.insert(0.0, rawtext)
         text['state'] = 'disabled'
         text.focus_set()
 
-        scroll.pack(side='right', fill='y')
-        text.pack(side='left', expand=True, fill='both')
+        # vertical scrollbar
+        self.yscroll = yscroll = AutoHiddenScrollbar(self, orient=VERTICAL,
+                                                     takefocus=False,
+                                                     command=text.yview)
+        text['yscrollcommand'] = yscroll.set
+        yscroll.grid(row=0, column=1, sticky=N+S)
+
+        if wrap == 'none':
+            # horizontal scrollbar
+            self.xscroll = xscroll = AutoHiddenScrollbar(self, orient=HORIZONTAL,
+                                                         takefocus=False,
+                                                         command=text.xview)
+            text['xscrollcommand'] = xscroll.set
+            xscroll.grid(row=1, column=0, sticky=E+W)
 
 
 class ViewFrame(Frame):
     "Display TextFrame and Close button."
-    def __init__(self, parent, text):
+    def __init__(self, parent, text, wrap='word'):
         super().__init__(parent)
         self.parent = parent
         self.bind('<Return>', self.ok)
         self.bind('<Escape>', self.ok)
-        self.textframe = TextFrame(self, text)
+        self.textframe = TextFrame(self, text, wrap=wrap)
         self.button_ok = button_ok = Button(
                 self, text='Close', command=self.ok, takefocus=False)
         self.textframe.pack(side='top', expand=True, fill='both')
@@ -55,7 +87,7 @@ class ViewFrame(Frame):
 class ViewWindow(Toplevel):
     "A simple text viewer dialog for IDLE."
 
-    def __init__(self, parent, title, text, modal=True,
+    def __init__(self, parent, title, text, modal=True, wrap='word',
                  *, _htest=False, _utest=False):
         """Show the given text in a scrollable window with a 'close' button.
 
@@ -65,6 +97,7 @@ class ViewWindow(Toplevel):
         parent - parent of this dialog
         title - string which is title of popup dialog
         text - text to display in dialog
+        wrap - type of text wrapping to use ('word', 'char' or 'none')
         _htest - bool; change box location when running htest.
         _utest - bool; don't wait_window when running unittest.
         """
@@ -76,7 +109,7 @@ class ViewWindow(Toplevel):
         self.geometry(f'=750x500+{x}+{y}')
 
         self.title(title)
-        self.viewframe = ViewFrame(self, text)
+        self.viewframe = ViewFrame(self, text, wrap=wrap)
         self.protocol("WM_DELETE_WINDOW", self.ok)
         self.button_ok = button_ok = Button(self, text='Close',
                                             command=self.ok, takefocus=False)
@@ -96,20 +129,22 @@ class ViewWindow(Toplevel):
         self.destroy()
 
 
-def view_text(parent, title, text, modal=True, _utest=False):
+def view_text(parent, title, text, modal=True, wrap='word', _utest=False):
     """Create text viewer for given text.
 
     parent - parent of this dialog
     title - string which is the title of popup dialog
     text - text to display in this dialog
+    wrap - type of text wrapping to use ('word', 'char' or 'none')
     modal - controls if users can interact with other windows while this
             dialog is displayed
     _utest - bool; controls wait_window on unittest
     """
-    return ViewWindow(parent, title, text, modal, _utest=_utest)
+    return ViewWindow(parent, title, text, modal, wrap=wrap, _utest=_utest)
 
 
-def view_file(parent, title, filename, encoding, modal=True, _utest=False):
+def view_file(parent, title, filename, encoding, modal=True, wrap='word',
+              _utest=False):
     """Create text viewer for text in filename.
 
     Return error message if file cannot be read.  Otherwise calls view_text
@@ -127,7 +162,8 @@ def view_file(parent, title, filename, encoding, modal=True, _utest=False):
                   message=str(err),
                   parent=parent)
     else:
-        return view_text(parent, title, contents, modal, _utest=_utest)
+        return view_text(parent, title, contents, modal, wrap=wrap,
+                         _utest=_utest)
     return None