Class: CSVDecision::Matchers::Pattern

Inherits:
Matcher
  • Object
show all
Defined in:
lib/csv_decision/matchers/pattern.rb

Overview

Match cell against a regular expression pattern - e.g., =~ hot|col or .OPT.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Pattern

Returns a new instance of Pattern

Parameters:

  • options (Hash{Symbol=>Object}) (defaults to: {}) —

    Used to determine the value of regexp_implicit:.



76
77
78
79
 
# File 'lib/csv_decision/matchers/pattern.rb', line 76

def initialize(options = {})
  # By default regexp's must have an explicit comparator
  @regexp_explicit = !options[:regexp_implicit]
end

Class Method Details

.matches?(cell, regexp_explicit:) ⇒ Boolean

Returns:

  • (Boolean) 


62
63
64
65
66
67
68
69
70
71
72
73
 
# File 'lib/csv_decision/matchers/pattern.rb', line 62

def self.matches?(cell, regexp_explicit:)
  comparator, value = regexp?(cell: cell, explicit: regexp_explicit)

  # We could not find a regexp pattern - maybe it's a simple string or something else?
  return false unless comparator

  # No need for a regular expression if we have simple string inequality
  pattern = comparator == '!=' ? value : Matchers.regexp(value)

  Proc.with(type: :proc,
            function: PATTERN_LAMBDAS[comparator].curry[pattern].freeze)
end

.parse(comparator:, value:) ⇒ Object 



40
41
42
43
44
45
46
47
48
49
50
51
 
# File 'lib/csv_decision/matchers/pattern.rb', line 40

def self.parse(comparator:, value:)
  return false if value.blank?

  # We cannot do a regexp comparison against a symbol name.
  # (Maybe we should add this feature?)
  return if value[0] == ':'

  # If no comparator then the implicit option must be on
  comparator = regexp_implicit(value) if comparator.nil?

  [comparator, value]
end

.regexp_implicit(value) ⇒ Object 



53
54
55
56
57
58
59
60
 
# File 'lib/csv_decision/matchers/pattern.rb', line 53

def self.regexp_implicit(value)
  # rubocop: disable Style/CaseEquality
  return unless /\W/ === value
  # rubocop: enable Style/CaseEquality

  # Make the implict comparator explict
  '=~'
end

Instance Method Details

#matches?(cell) ⇒ false, CSVDecision::Proc

Recognise a regular expression pattern - e.g., =~ on|off or !~ OPT.*. If the option regexp_implicit: true has been set, then cells may omit the =~ comparator so long as they contain non-word characters typically used in regular expressions such as * and ..

Parameters:

  • cell (String) —

    Data row cell.

Returns:

  • (false, CSVDecision::Proc) —

    Returns false if this cell is not a match; otherwise returns the CSVDecision::Proc object indicating if this is a constant or some type of function.



86
87
88
 
# File 'lib/csv_decision/matchers/pattern.rb', line 86

def matches?(cell)
  Pattern.matches?(cell, regexp_explicit: @regexp_explicit)
end