Issue #12288: Consider '0' and '0.0' as valid initialvalue for tkinter SimpleDialog.

Lib/tkinter/simpledialog.py

@@ -282,7 +282,7 @@ def body(self, master):
         self.entry = Entry(master, name="entry")
         self.entry.grid(row=1, padx=5, sticky=W+E)
 
-        if self.initialvalue:
+        if self.initialvalue is not None:
             self.entry.insert(0, self.initialvalue)
             self.entry.select_range(0, END)
 

Misc/ACKS

@@ -700,6 +700,7 @@ Piotr Meyer
 Alexis Métaireau
 Steven Miale
 Trent Mick
+Tom Middleton
 Stan Mihai
 Stefan Mihaila
 Aristotelis Mikropoulos

Misc/NEWS

@@ -339,6 +339,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #12288: Consider '0' and '0.0' as valid initialvalue
+  for tkinter SimpleDialog.
+
 - Issue #15489: Add a __sizeof__ implementation for BytesIO objects.
   Patch by Serhiy Storchaka.