Class: Hike::CachedTrail

Inherits:
Object
  • Object
show all
Includes:
FileUtils
Defined in:
lib/hike/cached_trail.rb

Overview

‘CachedTrail` is an internal cached variant of `Trail`. It assumes the file system does not change between `find` calls. All `stat` and `entries` calls are cached for the lifetime of the `CachedTrail` object.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(root, paths, extensions, aliases) ⇒ CachedTrail

‘CachedTrail.new` is an internal method. Instead of constructing it directly, create a `Trail` and call `Trail#CachedTrail`.



20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
 
# File 'lib/hike/cached_trail.rb', line 20

def initialize(root, paths, extensions, aliases)
  @root = root.to_s

  # Freeze is used here so an error is throw if a mutator method
  # is called on the array. Mutating `@paths`, `@extensions`, or
  # `@aliases` would have unpredictable results.
  @paths      = paths.dup.freeze
  @extensions = extensions.dup.freeze

  # Create a reverse mapping from extension to possible aliases.
  @aliases = aliases.dup.freeze
  @reverse_aliases = @aliases.inject({}) { |h, (k, a)|
    (h[a] ||= []) << k; h
  }

  @stats    = Hash.new { |h, k| h[k] = FileUtils.stat(k) }
  @entries  = Hash.new { |h, k| h[k] = FileUtils.entries(k) }
  @patterns = Hash.new { |h, k| h[k] = pattern_for(k) }
end

Instance Attribute Details

#aliases ⇒ Object (readonly)

‘CachedTrail#aliases` is an immutable `Hash` mapping an extension to an `Array` of aliases.



16
17
18
 
# File 'lib/hike/cached_trail.rb', line 16

def aliases
  @aliases
end

#extensions ⇒ Object (readonly)

‘CachedTrail#extensions` is an immutable `Extensions` collection.



12
13
14
 
# File 'lib/hike/cached_trail.rb', line 12

def extensions
  @extensions
end

#paths ⇒ Object (readonly)

‘CachedTrail#paths` is an immutable `Paths` collection.



9
10
11
 
# File 'lib/hike/cached_trail.rb', line 9

def paths
  @paths
end

#root ⇒ Object (readonly)

‘CachedTrail#root` returns root path as a `String`. This attribute is immutable.



41
42
43
 
# File 'lib/hike/cached_trail.rb', line 41

def root
  @root
end

Instance Method Details

#cached ⇒ Object Also known as: index

‘CachedTrail#cached` returns `self` to be compatable with the `Trail` interface.



44
45
46
 
# File 'lib/hike/cached_trail.rb', line 44

def cached
  self
end

#entries(path) ⇒ Object

A cached version of ‘Dir.entries` that filters out `.` files and `~` swap files. Returns an empty `Array` if the directory does not exist.



85
86
87
 
# File 'lib/hike/cached_trail.rb', line 85

def entries(path)
  @entries[path]
end

#find(*logical_paths) ⇒ Object

The real implementation of ‘find`. `Trail#find` generates a one time cache and delegates here.

See ‘Trail#find` for usage.



55
56
57
 
# File 'lib/hike/cached_trail.rb', line 55

def find(*logical_paths)
  find_all(*logical_paths).first
end

#find_all(*logical_paths, &block) ⇒ Object

The real implementation of ‘find_all`. `Trail#find_all` generates a one time index and delegates here.

See ‘Trail#find_all` for usage.



63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
 
# File 'lib/hike/cached_trail.rb', line 63

def find_all(*logical_paths, &block)
  return to_enum(__method__, *logical_paths) unless block_given?

  options = extract_options!(logical_paths)
  base_path = (options[:base_path] || root).to_s

  logical_paths.each do |logical_path|
    logical_path = logical_path.sub(/^\//, '')

    if relative?(logical_path)
      find_in_base_path(logical_path, base_path, &block)
    else
      find_in_paths(logical_path, &block)
    end
  end

  nil
end

#stat(path) ⇒ Object

A cached version of ‘File.stat`. Returns nil if the file does not exist.



91
92
93
 
# File 'lib/hike/cached_trail.rb', line 91

def stat(path)
  @stats[path]
end