class Opal::Hike::Index

‘Index` 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 `Index` object.

Attributes

extensions[R]

‘Index#extensions` is an immutable collection of extensions.

paths[R]

‘Index#paths` is an immutable collection of `Pathname`s.

Public Class Methods

new(root, paths, extensions) click to toggle source

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

# File lib/opal/hike.rb, line 41
def initialize(root, paths, extensions)
  @root = root

  # Freeze is used here so an error is throw if a mutator method
  # is called on the array. Mutating `@paths`, `@extensions`
  # would have unpredictable results.
  @paths      = paths.dup.freeze
  @extensions = extensions.dup.freeze
  @pathnames  = paths.map { |path| Pathname.new(path) }

  @stats    = {}
  @entries  = {}
  @patterns = {}
end

Public Instance Methods

entries(path) click to toggle source

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

# File lib/opal/hike.rb, line 86
def entries(path)
  @entries[path.to_s] ||= begin
    pathname = Pathname.new(path)
    if pathname.directory?
      pathname.entries.reject { |entry| entry.to_s =~ /^\.|~$|^\#.*\#$/ }.sort
    else
      []
    end
  end
end
find(logical_path) click to toggle source

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

See ‘Trail#find` for usage.

# File lib/opal/hike.rb, line 70
def find(logical_path)
  base_path = Pathname.new(@root)
  logical_path = Pathname.new(logical_path.sub(/^\//, ''))

  if logical_path.to_s =~ %r{^\.\.?/}
    find_in_base_path(logical_path, base_path) { |path| return path }
  else
    find_in_paths(logical_path) { |path| return path }
  end

  nil
end
index() click to toggle source

‘Index#index` returns `self` to be compatable with the `Trail` interface.

# File lib/opal/hike.rb, line 62
def index
  self
end
root() click to toggle source

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

# File lib/opal/hike.rb, line 57
def root
  @root.to_s
end
stat(path) click to toggle source

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

# File lib/opal/hike.rb, line 99
def stat(path)
  key = path.to_s
  if @stats.key?(key)
    @stats[key]
  elsif File.exist?(path)
    @stats[key] = File.stat(path)
  else
    @stats[key] = nil
  end
end

Protected Instance Methods

build_pattern_for(basename) click to toggle source

Returns a ‘Regexp` that matches the allowed extensions.

pattern_for("index.html") #=> /^index(.html|.htm)(.builder|.erb)*$/
# File lib/opal/hike.rb, line 167
def build_pattern_for(basename)
  extension_pattern = extensions.map { |e| Regexp.escape(e) }.join('|')
  /^#{basename}(?:#{extension_pattern})*$/
end
extract_options!(arguments) click to toggle source
# File lib/opal/hike.rb, line 112
def extract_options!(arguments)
  arguments.last.is_a?(Hash) ? arguments.pop.dup : {}
end
find_in_base_path(logical_path, base_path, &block) click to toggle source

Finds relative logical path, ‘../test/test_trail`. Requires a `base_path` for reference.

# File lib/opal/hike.rb, line 126
def find_in_base_path(logical_path, base_path, &block)
  candidate = base_path.join(logical_path)
  dirname, basename = candidate.split
  match(dirname, basename, &block) if paths_contain?(dirname)
end
find_in_paths(logical_path, &block) click to toggle source

Finds logical path across all ‘paths`

# File lib/opal/hike.rb, line 117
def find_in_paths(logical_path, &block)
  dirname, basename = logical_path.split
  @pathnames.each do |base_path|
    match(base_path.join(dirname), basename, &block)
  end
end
match(dirname, basename) { |pathname| ... } click to toggle source

Checks if the path is actually on the file system and performs any syscalls if necessary.

# File lib/opal/hike.rb, line 134
def match(dirname, basename)
  # Potential `entries` syscall
  matches = entries(dirname)

  pattern = pattern_for(basename)
  matches = matches.select { |m| m.to_s =~ pattern }

  sort_matches(matches, basename).each do |path|
    pathname = dirname.join(path)

    # Potential `stat` syscall
    stat = stat(pathname)

    # Exclude directories
    if stat && stat.file?
      yield pathname.to_s
    end
  end
end
paths_contain?(dirname) click to toggle source

Returns true if ‘dirname` is a subdirectory of any of the `paths`

# File lib/opal/hike.rb, line 155
def paths_contain?(dirname)
  paths.any? { |path| dirname.to_s[0, path.length] == path }
end
pattern_for(basename) click to toggle source

Cache results of ‘build_pattern_for`

# File lib/opal/hike.rb, line 160
def pattern_for(basename)
  @patterns[basename] ||= build_pattern_for(basename)
end
sort_matches(matches, basename) click to toggle source

Sorts candidate matches by their extension priority. Extensions in the front of the ‘extensions` carry more weight.

# File lib/opal/hike.rb, line 175
def sort_matches(matches, basename)
  matches.sort_by do |match|
    extnames = match.sub(basename.to_s, '').to_s.scan(/\.[^.]+/)
    extnames.inject(0) do |sum, ext|
      index = extensions.index(ext)
      if index
        sum + index + 1
      else
        sum
      end
    end
  end
end