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-rw-r--r--actionpack/lib/action_dispatch/journey/visitors.rb127
1 files changed, 86 insertions, 41 deletions
diff --git a/actionpack/lib/action_dispatch/journey/visitors.rb b/actionpack/lib/action_dispatch/journey/visitors.rb
index 52b4c8b489..537c9b2f5c 100644
--- a/actionpack/lib/action_dispatch/journey/visitors.rb
+++ b/actionpack/lib/action_dispatch/journey/visitors.rb
@@ -92,6 +92,45 @@ module ActionDispatch
end
end
+ class FunctionalVisitor # :nodoc:
+ DISPATCH_CACHE = {}
+
+ def accept(node, seed)
+ visit(node, seed)
+ end
+
+ def visit node, seed
+ send(DISPATCH_CACHE[node.type], node, seed)
+ end
+
+ def binary(node, seed)
+ visit(node.right, visit(node.left, seed))
+ end
+ def visit_CAT(n, seed); binary(n, seed); end
+
+ def nary(node, seed)
+ node.children.inject(seed) { |s, c| visit(c, s) }
+ end
+ def visit_OR(n, seed); nary(n, seed); end
+
+ def unary(node, seed)
+ visit(node.left, seed)
+ end
+ def visit_GROUP(n, seed); unary(n, seed); end
+ def visit_STAR(n, seed); unary(n, seed); end
+
+ def terminal(node, seed); seed; end
+ def visit_LITERAL(n, seed); terminal(n, seed); end
+ def visit_SYMBOL(n, seed); terminal(n, seed); end
+ def visit_SLASH(n, seed); terminal(n, seed); end
+ def visit_DOT(n, seed); terminal(n, seed); end
+
+ instance_methods(false).each do |pim|
+ next unless pim =~ /^visit_(.*)$/
+ DISPATCH_CACHE[$1.to_sym] = pim
+ end
+ end
+
class FormatBuilder < Visitor # :nodoc:
def accept(node); Journey::Format.new(super); end
def terminal(node); [node.left]; end
@@ -117,104 +156,110 @@ module ActionDispatch
end
# Loop through the requirements AST
- class Each < Visitor # :nodoc:
- attr_reader :block
-
- def initialize(block)
- @block = block
- end
-
- def visit(node)
+ class Each < FunctionalVisitor # :nodoc:
+ def visit(node, block)
block.call(node)
super
end
+
+ INSTANCE = new
end
- class String < Visitor # :nodoc:
+ class String < FunctionalVisitor # :nodoc:
private
- def binary(node)
- [visit(node.left), visit(node.right)].join
+ def binary(node, seed)
+ visit(node.right, visit(node.left, seed))
end
- def nary(node)
- node.children.map { |c| visit(c) }.join '|'
+ def nary(node, seed)
+ last_child = node.children.last
+ node.children.inject(seed) { |s, c|
+ string = visit(c, s)
+ string << "|".freeze unless last_child == c
+ string
+ }
end
- def terminal(node)
- node.left
+ def terminal(node, seed)
+ seed + node.left
end
- def visit_GROUP(node)
- "(#{visit(node.left)})"
+ def visit_GROUP(node, seed)
+ visit(node.left, seed << "(".freeze) << ")".freeze
end
+
+ INSTANCE = new
end
- class Dot < Visitor # :nodoc:
+ class Dot < FunctionalVisitor # :nodoc:
def initialize
@nodes = []
@edges = []
end
- def accept(node)
+ def accept(node, seed = [[], []])
super
+ nodes, edges = seed
<<-eodot
digraph parse_tree {
size="8,5"
node [shape = none];
edge [dir = none];
- #{@nodes.join "\n"}
- #{@edges.join("\n")}
+ #{nodes.join "\n"}
+ #{edges.join("\n")}
}
eodot
end
private
- def binary(node)
- node.children.each do |c|
- @edges << "#{node.object_id} -> #{c.object_id};"
- end
+ def binary(node, seed)
+ seed.last.concat node.children.map { |c|
+ "#{node.object_id} -> #{c.object_id};"
+ }
super
end
- def nary(node)
- node.children.each do |c|
- @edges << "#{node.object_id} -> #{c.object_id};"
- end
+ def nary(node, seed)
+ seed.last.concat node.children.map { |c|
+ "#{node.object_id} -> #{c.object_id};"
+ }
super
end
- def unary(node)
- @edges << "#{node.object_id} -> #{node.left.object_id};"
+ def unary(node, seed)
+ seed.last << "#{node.object_id} -> #{node.left.object_id};"
super
end
- def visit_GROUP(node)
- @nodes << "#{node.object_id} [label=\"()\"];"
+ def visit_GROUP(node, seed)
+ seed.first << "#{node.object_id} [label=\"()\"];"
super
end
- def visit_CAT(node)
- @nodes << "#{node.object_id} [label=\"○\"];"
+ def visit_CAT(node, seed)
+ seed.first << "#{node.object_id} [label=\"○\"];"
super
end
- def visit_STAR(node)
- @nodes << "#{node.object_id} [label=\"*\"];"
+ def visit_STAR(node, seed)
+ seed.first << "#{node.object_id} [label=\"*\"];"
super
end
- def visit_OR(node)
- @nodes << "#{node.object_id} [label=\"|\"];"
+ def visit_OR(node, seed)
+ seed.first << "#{node.object_id} [label=\"|\"];"
super
end
- def terminal(node)
+ def terminal(node, seed)
value = node.left
- @nodes << "#{node.object_id} [label=\"#{value}\"];"
+ seed.first << "#{node.object_id} [label=\"#{value}\"];"
+ seed
end
+ INSTANCE = new
end
end
end