bpo-38041: Refine IDLE Shell restart lines. (GH-15709)
Restart lines now always start with '=' and never end with ' ' and fill the width of the window unless that would require ending with ' ', which could be wrapped by itself and possible confusing the user.
diff --git a/Lib/idlelib/pyshell.py b/Lib/idlelib/pyshell.py
index ea94655..08716a9 100755
--- a/Lib/idlelib/pyshell.py
+++ b/Lib/idlelib/pyshell.py
@@ -387,6 +387,19 @@
"Override the base class - just re-raise EOFError"
raise EOFError
+def restart_line(width, filename): # See bpo-38141.
+ """Return width long restart line formatted with filename.
+
+ Fill line with balanced '='s, with any extras and at least one at
+ the beginning. Do not end with a trailing space.
+ """
+ tag = f"= RESTART: {filename or 'Shell'} ="
+ if width >= len(tag):
+ div, mod = divmod((width -len(tag)), 2)
+ return f"{(div+mod)*'='}{tag}{div*'='}"
+ else:
+ return tag[:-2] # Remove ' ='.
+
class ModifiedInterpreter(InteractiveInterpreter):
@@ -491,9 +504,8 @@
console.stop_readline()
# annotate restart in shell window and mark it
console.text.delete("iomark", "end-1c")
- tag = 'RESTART: ' + (filename if filename else 'Shell')
- halfbar = ((int(console.width) -len(tag) - 4) // 2) * '='
- console.write("\n{0} {1} {0}".format(halfbar, tag))
+ console.write('\n')
+ console.write(restart_line(console.width, filename))
console.text.mark_set("restart", "end-1c")
console.text.mark_gravity("restart", "left")
if not filename: