Class: Linguist::Heuristics

Inherits:
Object
  • Object
show all
Defined in:
lib/linguist/heuristics.rb

Overview

A collection of simple heuristics that can be used to better analyze languages.

Constant Summary collapse

ObjectiveCRegex =

Common heuristics

/^\s*(@(interface|class|protocol|property|end|synchronised|selector|implementation)\b|#import\s+.+\.h[">])/

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(extensions, &heuristic) ⇒ Heuristics

Internal



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# File 'lib/linguist/heuristics.rb', line 52

def initialize(extensions, &heuristic)
  @extensions = extensions
  @heuristic = heuristic
end

Class Method Details

.call(blob, candidates) ⇒ Object

Public: Use heuristics to detect language of the blob.

blob - An object that quacks like a blob. possible_languages - Array of Language objects

Examples

Heuristics.call(FileBlob.new("path/to/file"), [
  Language["Ruby"], Language["Python"]
])

Returns an Array of languages, or empty if none matched or were inconclusive.



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# File 'lib/linguist/heuristics.rb', line 16

def self.call(blob, candidates)
  data = blob.data

  @heuristics.each do |heuristic|
    if heuristic.matches?(blob.name)
      languages = Array(heuristic.call(data))
      return languages if languages.any? || languages.all? { |l| candidates.include?(l) }
    end
  end

  [] # No heuristics matched
end

.disambiguate(*extensions, &heuristic) ⇒ Object

Internal: Define a new heuristic.

languages - String names of languages to disambiguate. heuristic - Block which takes data as an argument and returns a Language or nil.

Examples

disambiguate ".pm" do |data|
  if data.include?("use strict")
    Language["Perl"]
  elsif /^[^#]+:-/.match(data)
    Language["Prolog"]
  end
end



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# File 'lib/linguist/heuristics.rb', line 44

def self.disambiguate(*extensions, &heuristic)
  @heuristics << new(extensions, &heuristic)
end

Instance Method Details

#call(data) ⇒ Object

Internal: Perform the heuristic



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# File 'lib/linguist/heuristics.rb', line 64

def call(data)
  @heuristic.call(data)
end

#matches?(filename) ⇒ Boolean

Internal: Check if this heuristic matches the candidate languages.

Returns:

  • (Boolean) 


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# File 'lib/linguist/heuristics.rb', line 58

def matches?(filename)
  filename = filename.downcase
  @extensions.any? { |ext| filename.end_with?(ext) }
end