1""" Indentation utilities for Cog. 

2 http://nedbatchelder.com/code/cog 

3 

4 Copyright 2004-2019, Ned Batchelder. 

5""" 

6 

7from __future__ import absolute_import 

8 

9import re 

10 

11from .backward import string_types, bytes_types, to_bytes 

12 

13def whitePrefix(strings): 

14 """ Determine the whitespace prefix common to all non-blank lines 

15 in the argument list. 

16 """ 

17 # Remove all blank lines from the list 

18 strings = [s for s in strings if s.strip() != ''] 

19 

20 if not strings: return '' 

21 

22 # Find initial whitespace chunk in the first line. 

23 # This is the best prefix we can hope for. 

24 pat = r'\s*' 

25 if isinstance(strings[0], bytes_types): 25 ↛ 26line 25 didn't jump to line 26, because the condition on line 25 was never true

26 pat = to_bytes(pat) 

27 prefix = re.match(pat, strings[0]).group(0) 

28 

29 # Loop over the other strings, keeping only as much of 

30 # the prefix as matches each string. 

31 for s in strings: 

32 for i in range(len(prefix)): 

33 if prefix[i] != s[i]: 33 ↛ 34line 33 didn't jump to line 34, because the condition on line 33 was never true

34 prefix = prefix[:i] 

35 break 

36 return prefix 

37 

38def reindentBlock(lines, newIndent=''): 

39 """ Take a block of text as a string or list of lines. 

40 Remove any common whitespace indentation. 

41 Re-indent using newIndent, and return it as a single string. 

42 """ 

43 sep, nothing = '\n', '' 

44 if isinstance(lines, bytes_types): 44 ↛ 45line 44 didn't jump to line 45, because the condition on line 44 was never true

45 sep, nothing = b'\n', b'' 

46 if isinstance(lines, string_types): 

47 lines = lines.split(sep) 

48 oldIndent = whitePrefix(lines) 

49 outLines = [] 

50 for l in lines: 

51 if oldIndent: 

52 l = l.replace(oldIndent, nothing, 1) 

53 if l and newIndent: 

54 l = newIndent + l 

55 outLines.append(l) 

56 return sep.join(outLines) 

57 

58def commonPrefix(strings): 

59 """ Find the longest string that is a prefix of all the strings. 

60 """ 

61 if not strings: 61 ↛ 62line 61 didn't jump to line 62, because the condition on line 61 was never true

62 return '' 

63 prefix = strings[0] 

64 for s in strings: 

65 if len(s) < len(prefix): 

66 prefix = prefix[:len(s)] 

67 if not prefix: 

68 return '' 

69 for i in range(len(prefix)): 

70 if prefix[i] != s[i]: 

71 prefix = prefix[:i] 

72 break 

73 return prefix