module Sprockets::Utils
Internal: Utils
, we didn't know where else to put it! Functions may eventually be shuffled into more specific drawers.
Constants
- UNBOUND_METHODS_BIND_TO_ANY_OBJECT
Internal: Feature detect if UnboundMethods can bind to any Object or just Objects that share the same super class. Basically if RUBY_VERSION >= 2.
Public Instance Methods
Internal: Accumulate asset source to buffer and append a trailing semicolon if necessary.
buf - String buffer to append to source - String source to append
Returns buf String.
# File lib/sprockets/utils.rb, line 104 def concat_javascript_sources(buf, source) if source.bytesize > 0 buf << source # If the source contains non-ASCII characters, indexing on it becomes O(N). # This will lead to O(N^2) performance in string_end_with_semicolon?, so we should use 32 bit encoding to make sure indexing stays O(1) source = source.encode(Encoding::UTF_32LE) unless source.ascii_only? if !string_end_with_semicolon?(source) buf << ";\n" elsif source[source.size - 1].ord != 0x0A buf << "\n" end end buf end
Internal: Post-order Depth-First search algorithm.
Used for resolving asset dependencies.
initial - Initial Array of nodes to traverse. block -
node - Current node to get children of
Returns a Set of nodes.
# File lib/sprockets/utils.rb, line 190 def dfs(initial) nodes, seen = Set.new, Set.new stack = Array(initial).reverse while node = stack.pop if seen.include?(node) nodes.add(node) else seen.add(node) stack.push(node) stack.concat(Array(yield node).reverse) end end nodes end
Internal: Post-order Depth-First search algorithm that gathers all paths along the way.
TODO: Rename function.
path - Initial Array node path block -
node - Current node to get children of
Returns an Array of node Arrays.
# File lib/sprockets/utils.rb, line 217 def dfs_paths(path) paths = [] stack, seen = [path], Set.new while path = stack.pop if !seen.include?(path.last) seen.add(path.last) paths << path if path.size > 1 Array(yield path.last).reverse_each do |node| stack.push(path + [node]) end end end
Internal: Check if object can safely be .dup'd.
Similar to ActiveSupport duplicable?
check.
obj - Any Object
Returns false if .dup would raise a TypeError, otherwise true.
# File lib/sprockets/utils.rb, line 16 def duplicable?(obj) if RUBY_VERSION >= "2.4.0" true else case obj when NilClass, FalseClass, TrueClass, Symbol, Numeric false else true end end end
Internal: Duplicate and store key/value on new frozen hash.
Similar to Hash#store for nested frozen hashes.
hash - Hash key - Object keys. Use multiple keys for nested hashes. block - Receives current value at key.
Examples
config = {paths: ["/bin", "/sbin"]}.freeze new_config = hash_reassoc(config, :paths) do |paths| paths << "/usr/local/bin" end
Returns duplicated frozen Hash.
# File lib/sprockets/utils.rb, line 63 def hash_reassoc(hash, *keys, &block) if keys.size == 1 hash_reassoc1(hash, keys[0], &block) else hash_reassoc1(hash, keys[0]) do |value| hash_reassoc(value, *keys[1..-1], &block) end end end
Internal: Duplicate and store key/value on new frozen hash.
Seperated for recursive calls, always use hash_reassoc
(hash, *keys).
hash - Hash key - Object key
Returns Hash.
# File lib/sprockets/utils.rb, line 37 def hash_reassoc1(hash, key) hash = hash.dup if hash.frozen? old_value = hash[key] old_value = old_value.dup if duplicable?(old_value) new_value = yield old_value new_value.freeze if duplicable?(new_value) hash.store(key, new_value) hash.freeze end
Internal: Inject into target module for the duration of the block.
mod - Module
Returns result of block.
# File lib/sprockets/utils.rb, line 155 def module_include(base, mod) old_methods = {} mod.instance_methods.each do |sym| old_methods[sym] = base.instance_method(sym) if base.method_defined?(sym) end unless UNBOUND_METHODS_BIND_TO_ANY_OBJECT base.send(:include, mod) unless base < mod end mod.instance_methods.each do |sym| method = mod.instance_method(sym) base.send(:define_method, sym, method) end yield ensure mod.instance_methods.each do |sym| base.send(:undef_method, sym) if base.method_defined?(sym) end old_methods.each do |sym, method| base.send(:define_method, sym, method) end end
Internal: Prepends a leading “.” to an extension if its missing.
normalize_extension("js") # => ".js" normalize_extension(".css") # => ".css"
# File lib/sprockets/utils.rb, line 130 def normalize_extension(extension) extension = extension.to_s if extension[/^\./] extension else ".#{extension}" end end
Internal: Check if string has a trailing semicolon.
str - String
Returns true or false.
# File lib/sprockets/utils.rb, line 78 def string_end_with_semicolon?(str) i = str.size - 1 while i >= 0 c = str[i].ord i -= 1 # Need to compare against the ordinals because the string can be UTF_8 or UTF_32LE encoded # 0x0A == "\n" # 0x20 == " " # 0x09 == "\t" # 0x3B == ";" unless c == 0x0A || c == 0x20 || c == 0x09 return c === 0x3B end end true end