bpo-32989: IDLE - fix bad editor call of pyparse method (GH-5968)
Fix comments and add tests for editor newline_and_indent_event method.
Remove unused None default for function parameter of pyparse find_good_parse_start method
and code triggered by that default.
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
diff --git a/Lib/idlelib/editor.py b/Lib/idlelib/editor.py
index 92dcf57..c9f1a16 100644
--- a/Lib/idlelib/editor.py
+++ b/Lib/idlelib/editor.py
@@ -1342,38 +1342,51 @@
text.undo_block_stop()
def newline_and_indent_event(self, event):
+ """Insert a newline and indentation after Enter keypress event.
+
+ Properly position the cursor on the new line based on information
+ from the current line. This takes into account if the current line
+ is a shell prompt, is empty, has selected text, contains a block
+ opener, contains a block closer, is a continuation line, or
+ is inside a string.
+ """
text = self.text
first, last = self.get_selection_indices()
text.undo_block_start()
- try:
+ try: # Close undo block and expose new line in finally clause.
if first and last:
text.delete(first, last)
text.mark_set("insert", first)
line = text.get("insert linestart", "insert")
+
+ # Count leading whitespace for indent size.
i, n = 0, len(line)
while i < n and line[i] in " \t":
- i = i+1
+ i += 1
if i == n:
- # the cursor is in or at leading indentation in a continuation
- # line; just inject an empty line at the start
+ # The cursor is in or at leading indentation in a continuation
+ # line; just inject an empty line at the start.
text.insert("insert linestart", '\n')
return "break"
indent = line[:i]
- # strip whitespace before insert point unless it's in the prompt
+
+ # Strip whitespace before insert point unless it's in the prompt.
i = 0
while line and line[-1] in " \t" and line != self.prompt_last_line:
line = line[:-1]
- i = i+1
+ i += 1
if i:
text.delete("insert - %d chars" % i, "insert")
- # strip whitespace after insert point
+
+ # Strip whitespace after insert point.
while text.get("insert") in " \t":
text.delete("insert")
- # start new line
+
+ # Insert new line.
text.insert("insert", '\n')
- # adjust indentation for continuations and block
- # open/close first need to find the last stmt
+ # Adjust indentation for continuations and block open/close.
+ # First need to find the last statement.
lno = index2line(text.index('insert'))
y = pyparse.Parser(self.indentwidth, self.tabwidth)
if not self.prompt_last_line:
@@ -1383,7 +1396,7 @@
rawtext = text.get(startatindex, "insert")
y.set_code(rawtext)
bod = y.find_good_parse_start(
- self._build_char_in_string_func(startatindex))
+ self._build_char_in_string_func(startatindex))
if bod is not None or startat == 1:
break
y.set_lo(bod or 0)
@@ -1399,26 +1412,26 @@
c = y.get_continuation_type()
if c != pyparse.C_NONE:
- # The current stmt hasn't ended yet.
+ # The current statement hasn't ended yet.
if c == pyparse.C_STRING_FIRST_LINE:
- # after the first line of a string; do not indent at all
+ # After the first line of a string do not indent at all.
pass
elif c == pyparse.C_STRING_NEXT_LINES:
- # inside a string which started before this line;
- # just mimic the current indent
+ # Inside a string which started before this line;
+ # just mimic the current indent.
text.insert("insert", indent)
elif c == pyparse.C_BRACKET:
- # line up with the first (if any) element of the
+ # Line up with the first (if any) element of the
# last open bracket structure; else indent one
# level beyond the indent of the line with the
- # last open bracket
+ # last open bracket.
self.reindent_to(y.compute_bracket_indent())
elif c == pyparse.C_BACKSLASH:
- # if more than one line in this stmt already, just
+ # If more than one line in this statement already, just
# mimic the current indent; else if initial line
# has a start on an assignment stmt, indent to
# beyond leftmost =; else to beyond first chunk of
- # non-whitespace on initial line
+ # non-whitespace on initial line.
if y.get_num_lines_in_stmt() > 1:
text.insert("insert", indent)
else:
@@ -1427,9 +1440,9 @@
assert 0, "bogus continuation type %r" % (c,)
return "break"
- # This line starts a brand new stmt; indent relative to
+ # This line starts a brand new statement; indent relative to
# indentation of initial line of closest preceding
- # interesting stmt.
+ # interesting statement.
indent = y.get_base_indent_string()
text.insert("insert", indent)
if y.is_block_opener():