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author | Terry Jan Reedy <tjreedy@udel.edu> | 2016-05-22 23:10:31 (GMT) |
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committer | Terry Jan Reedy <tjreedy@udel.edu> | 2016-05-22 23:10:31 (GMT) |
commit | 0d9220e162f1e5f8caa3d7ebaa54665776d361a1 (patch) | |
tree | a4fa9f7cafdfc93fde86b8ffd6088d739bb93e01 /Lib/idlelib/paragraph.py | |
parent | dc4f7c09cc934524a763498250e30123a0d9d2c5 (diff) | |
download | cpython-0d9220e162f1e5f8caa3d7ebaa54665776d361a1.zip cpython-0d9220e162f1e5f8caa3d7ebaa54665776d361a1.tar.gz cpython-0d9220e162f1e5f8caa3d7ebaa54665776d361a1.tar.bz2 |
Issue #24225: Rename many idlelib/*.py and idlelib/idle_test/test_*.py files.
Diffstat (limited to 'Lib/idlelib/paragraph.py')
-rw-r--r-- | Lib/idlelib/paragraph.py | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/Lib/idlelib/paragraph.py b/Lib/idlelib/paragraph.py new file mode 100644 index 0000000..7a9d185 --- /dev/null +++ b/Lib/idlelib/paragraph.py @@ -0,0 +1,195 @@ +"""Extension to format a paragraph or selection to a max width. + +Does basic, standard text formatting, and also understands Python +comment blocks. Thus, for editing Python source code, this +extension is really only suitable for reformatting these comment +blocks or triple-quoted strings. + +Known problems with comment reformatting: +* If there is a selection marked, and the first line of the + selection is not complete, the block will probably not be detected + as comments, and will have the normal "text formatting" rules + applied. +* If a comment block has leading whitespace that mixes tabs and + spaces, they will not be considered part of the same block. +* Fancy comments, like this bulleted list, aren't handled :-) +""" + +import re +from idlelib.configHandler import idleConf + +class FormatParagraph: + + menudefs = [ + ('format', [ # /s/edit/format dscherer@cmu.edu + ('Format Paragraph', '<<format-paragraph>>'), + ]) + ] + + def __init__(self, editwin): + self.editwin = editwin + + def close(self): + self.editwin = None + + def format_paragraph_event(self, event, limit=None): + """Formats paragraph to a max width specified in idleConf. + + If text is selected, format_paragraph_event will start breaking lines + at the max width, starting from the beginning selection. + + If no text is selected, format_paragraph_event uses the current + cursor location to determine the paragraph (lines of text surrounded + by blank lines) and formats it. + + The length limit parameter is for testing with a known value. + """ + if limit is None: + # The default length limit is that defined by pep8 + limit = idleConf.GetOption( + 'extensions', 'FormatParagraph', 'max-width', + type='int', default=72) + text = self.editwin.text + first, last = self.editwin.get_selection_indices() + if first and last: + data = text.get(first, last) + comment_header = get_comment_header(data) + else: + first, last, comment_header, data = \ + find_paragraph(text, text.index("insert")) + if comment_header: + newdata = reformat_comment(data, limit, comment_header) + else: + newdata = reformat_paragraph(data, limit) + text.tag_remove("sel", "1.0", "end") + + if newdata != data: + text.mark_set("insert", first) + text.undo_block_start() + text.delete(first, last) + text.insert(first, newdata) + text.undo_block_stop() + else: + text.mark_set("insert", last) + text.see("insert") + return "break" + +def find_paragraph(text, mark): + """Returns the start/stop indices enclosing the paragraph that mark is in. + + Also returns the comment format string, if any, and paragraph of text + between the start/stop indices. + """ + lineno, col = map(int, mark.split(".")) + line = text.get("%d.0" % lineno, "%d.end" % lineno) + + # Look for start of next paragraph if the index passed in is a blank line + while text.compare("%d.0" % lineno, "<", "end") and is_all_white(line): + lineno = lineno + 1 + line = text.get("%d.0" % lineno, "%d.end" % lineno) + first_lineno = lineno + comment_header = get_comment_header(line) + comment_header_len = len(comment_header) + + # Once start line found, search for end of paragraph (a blank line) + while get_comment_header(line)==comment_header and \ + not is_all_white(line[comment_header_len:]): + lineno = lineno + 1 + line = text.get("%d.0" % lineno, "%d.end" % lineno) + last = "%d.0" % lineno + + # Search back to beginning of paragraph (first blank line before) + lineno = first_lineno - 1 + line = text.get("%d.0" % lineno, "%d.end" % lineno) + while lineno > 0 and \ + get_comment_header(line)==comment_header and \ + not is_all_white(line[comment_header_len:]): + lineno = lineno - 1 + line = text.get("%d.0" % lineno, "%d.end" % lineno) + first = "%d.0" % (lineno+1) + + return first, last, comment_header, text.get(first, last) + +# This should perhaps be replaced with textwrap.wrap +def reformat_paragraph(data, limit): + """Return data reformatted to specified width (limit).""" + lines = data.split("\n") + i = 0 + n = len(lines) + while i < n and is_all_white(lines[i]): + i = i+1 + if i >= n: + return data + indent1 = get_indent(lines[i]) + if i+1 < n and not is_all_white(lines[i+1]): + indent2 = get_indent(lines[i+1]) + else: + indent2 = indent1 + new = lines[:i] + partial = indent1 + while i < n and not is_all_white(lines[i]): + # XXX Should take double space after period (etc.) into account + words = re.split("(\s+)", lines[i]) + for j in range(0, len(words), 2): + word = words[j] + if not word: + continue # Can happen when line ends in whitespace + if len((partial + word).expandtabs()) > limit and \ + partial != indent1: + new.append(partial.rstrip()) + partial = indent2 + partial = partial + word + " " + if j+1 < len(words) and words[j+1] != " ": + partial = partial + " " + i = i+1 + new.append(partial.rstrip()) + # XXX Should reformat remaining paragraphs as well + new.extend(lines[i:]) + return "\n".join(new) + +def reformat_comment(data, limit, comment_header): + """Return data reformatted to specified width with comment header.""" + + # Remove header from the comment lines + lc = len(comment_header) + data = "\n".join(line[lc:] for line in data.split("\n")) + # Reformat to maxformatwidth chars or a 20 char width, + # whichever is greater. + format_width = max(limit - len(comment_header), 20) + newdata = reformat_paragraph(data, format_width) + # re-split and re-insert the comment header. + newdata = newdata.split("\n") + # If the block ends in a \n, we dont want the comment prefix + # inserted after it. (Im not sure it makes sense to reformat a + # comment block that is not made of complete lines, but whatever!) + # Can't think of a clean solution, so we hack away + block_suffix = "" + if not newdata[-1]: + block_suffix = "\n" + newdata = newdata[:-1] + return '\n'.join(comment_header+line for line in newdata) + block_suffix + +def is_all_white(line): + """Return True if line is empty or all whitespace.""" + + return re.match(r"^\s*$", line) is not None + +def get_indent(line): + """Return the initial space or tab indent of line.""" + return re.match(r"^([ \t]*)", line).group() + +def get_comment_header(line): + """Return string with leading whitespace and '#' from line or ''. + + A null return indicates that the line is not a comment line. A non- + null return, such as ' #', will be used to find the other lines of + a comment block with the same indent. + """ + m = re.match(r"^([ \t]*#*)", line) + if m is None: return "" + return m.group(1) + +if __name__ == "__main__": + import unittest + unittest.main('idlelib.idle_test.test_formatparagraph', + verbosity=2, exit=False) |