Merge pull request #8 from luislavena/define-payload-type

Introduce types for forward compiler compatibility

Closes #7
This commit is contained in:
Luis Lavena 2016-04-16 17:06:16 -03:00
commit 08db441c9a
8 changed files with 190 additions and 109 deletions

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@ -4,6 +4,15 @@ All notable changes to Radix project will be documented in this file.
This project aims to comply with [Semantic Versioning](http://semver.org/),
so please check *Changed* and *Removed* notes before upgrading.
## [Unreleased]
### Fixed
- Improve forward compatibility with newer versions of the compiler by adding
missing types to solve type inference errors.
### Changed
- `Radix::Tree` now requires the usage of a type which will be used as node's
payload. See [README](README.md) for details.
## [0.2.1] - 2016-03-15
### Fixed
- Correct `Result#key` incorrect inferred type.

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@ -1,11 +1,11 @@
# Radix Tree
[![Build Status](https://travis-ci.org/luislavena/radix.svg?branch=master)](https://travis-ci.org/luislavena/radix)
[![docrystal.org](http://docrystal.org/badge.svg?style=round)](http://docrystal.org/github.com/luislavena/radix)
[Radix tree](https://en.wikipedia.org/wiki/Radix_tree) implementation for
Crystal language
[![Build Status](https://travis-ci.org/luislavena/radix.svg?branch=master)](https://travis-ci.org/luislavena/radix)
[![docrystal.org](http://docrystal.org/badge.svg?style=round)](http://docrystal.org/github.com/luislavena/radix)
## Installation
Add this to your application's `shard.yml`:
@ -18,12 +18,14 @@ dependencies:
## Usage
### Building Trees
You can associate a *payload* with each path added to the tree:
```crystal
require "radix"
tree = Radix::Tree.new
tree = Radix::Tree(Symbol).new
tree.add "/products", :products
tree.add "/products/featured", :featured
@ -34,6 +36,30 @@ if result.found?
end
```
The types allowed for payload are defined on Tree definition:
```crystal
tree = Radix::Tree(Symbol).new
# Good, since Symbol is allowed as payload
tree.add "/", :root
# Compilation error, Int32 is not allowed
tree.add "/meaning-of-life", 42
```
Can combine multiple types if needed:
```crystal
tree = Radix::Tree(Int32 | String | Symbol).new
tree.add "/", :root
tree.add "/meaning-of-life", 42
tree.add "/hello", "world"
```
### Lookup and placeholders
You can also extract values from placeholders (as named segments or globbing):
```crystal
@ -53,8 +79,8 @@ Please see `Radix::Tree#add` documentation for more usage examples.
Pretty much all Radix implementations have their limitations and this project
is no exception.
When designing and adding *paths* to build a Tree, please consider that two
different named parameters cannot share the same level:
When designing and adding *paths* to a Tree, please consider that two different
named parameters cannot share the same level:
```crystal
tree.add "/", :root

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@ -4,7 +4,7 @@ module Radix
describe Node do
describe "#key=" do
it "accepts change of key after initialization" do
node = Node.new("abc")
node = Node(Nil).new("abc")
node.key.should eq("abc")
node.key = "xyz"
@ -23,39 +23,45 @@ module Radix
node.payload.should eq(1_000)
end
# This example focuses on the internal representation of `payload`
# as inferred from supplied types and default values.
#
# We cannot compare `typeof` against `property!` since it excludes `Nil`
# from the possible types.
it "makes optional to provide a payload" do
node = Node.new("abc")
node = Node(Int32).new("abc")
node.payload?.should be_falsey
typeof(node.@payload).should eq(Int32 | Nil)
end
end
describe "#priority" do
it "calculates it based on key size" do
node = Node.new("a")
node = Node(Nil).new("a")
node.priority.should eq(1)
node = Node.new("abc")
node = Node(Nil).new("abc")
node.priority.should eq(3)
end
it "returns zero for catch all (globbed) key" do
node = Node.new("*filepath")
node = Node(Nil).new("*filepath")
node.priority.should eq(0)
node = Node.new("/src/*filepath")
node = Node(Nil).new("/src/*filepath")
node.priority.should eq(0)
end
it "returns one for keys with named parameters" do
node = Node.new(":query")
node = Node(Nil).new(":query")
node.priority.should eq(1)
node = Node.new("/search/:query")
node = Node(Nil).new("/search/:query")
node.priority.should eq(1)
end
it "changes when key changes" do
node = Node.new("a")
node = Node(Nil).new("a")
node.priority.should eq(1)
node.key = "abc"
@ -71,10 +77,10 @@ module Radix
describe "#sort!" do
it "orders children by priority" do
root = Node.new("/")
node1 = Node.new("a")
node2 = Node.new("bc")
node3 = Node.new("def")
root = Node(Int32).new("/")
node1 = Node(Int32).new("a", 1)
node2 = Node(Int32).new("bc", 2)
node3 = Node(Int32).new("def", 3)
root.children.push(node1, node2, node3)
root.sort!
@ -85,10 +91,10 @@ module Radix
end
it "orders catch all and named parameters lower than others" do
root = Node.new("/")
node1 = Node.new("*filepath")
node2 = Node.new("abc")
node3 = Node.new(":query")
root = Node(Int32).new("/")
node1 = Node(Int32).new("*filepath", 1)
node2 = Node(Int32).new("abc", 2)
node3 = Node(Int32).new(":query", 3)
root.children.push(node1, node2, node3)
root.sort!

View file

@ -5,15 +5,15 @@ module Radix
describe "#found?" do
context "a new instance" do
it "returns false when no payload is associated" do
result = Result.new
result = Result(Nil).new
result.found?.should be_false
end
end
context "with a payload" do
it "returns true" do
node = Node.new("/", :root)
result = Result.new
node = Node(Symbol).new("/", :root)
result = Result(Symbol).new
result.use node
result.found?.should be_true
@ -24,15 +24,15 @@ module Radix
describe "#key" do
context "a new instance" do
it "returns an empty key" do
result = Result.new
result = Result(Nil).new
result.key.should eq("")
end
end
context "given one used node" do
it "returns the node key" do
node = Node.new("/", :root)
result = Result.new
node = Node(Symbol).new("/", :root)
result = Result(Symbol).new
result.use node
result.key.should eq("/")
@ -41,9 +41,9 @@ module Radix
context "using multiple nodes" do
it "combines the node keys" do
node1 = Node.new("/", :root)
node2 = Node.new("about", :about)
result = Result.new
node1 = Node(Symbol).new("/", :root)
node2 = Node(Symbol).new("about", :about)
result = Result(Symbol).new
result.use node1
result.use node2
@ -54,8 +54,8 @@ module Radix
describe "#use" do
it "uses the node payload" do
node = Node.new("/", :root)
result = Result.new
node = Node(Symbol).new("/", :root)
result = Result(Symbol).new
result.payload?.should be_falsey
result.use node
@ -64,8 +64,8 @@ module Radix
end
it "allow not to assign payload" do
node = Node.new("/", :root)
result = Result.new
node = Node(Symbol).new("/", :root)
result = Result(Symbol).new
result.payload?.should be_falsey
result.use node, payload: false

View file

@ -3,7 +3,7 @@ require "../spec_helper"
# Silence deprecation warnings when running specs and allow
# capture them for inspection.
module Radix
class Tree
class Tree(T)
@show_deprecations = false
@stderr : MemoryIO?
@ -20,12 +20,15 @@ module Radix
end
end
# Simple Payload class
record Payload
module Radix
describe Tree do
context "a new instance" do
it "contains a root placeholder node" do
tree = Tree.new
tree.root.should be_a(Node)
tree = Tree(Symbol).new
tree.root.should be_a(Node(Symbol))
tree.root.payload?.should be_falsey
tree.root.placeholder?.should be_true
end
@ -34,9 +37,9 @@ module Radix
describe "#add" do
context "on a new instance" do
it "replaces placeholder with new node" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/abc", :abc
tree.root.should be_a(Node)
tree.root.should be_a(Node(Symbol))
tree.root.placeholder?.should be_false
tree.root.payload?.should be_truthy
tree.root.payload.should eq(:abc)
@ -45,7 +48,7 @@ module Radix
context "shared root" do
it "inserts properly adjacent nodes" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/a", :a
tree.add "/bc", :bc
@ -61,7 +64,7 @@ module Radix
end
it "inserts nodes with shared parent" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/abc", :abc
tree.add "/axyz", :axyz
@ -78,7 +81,7 @@ module Radix
end
it "inserts multiple parent nodes" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/admin/users", :users
tree.add "/admin/products", :products
@ -107,7 +110,7 @@ module Radix
end
it "inserts multiple nodes with mixed parents" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/authorizations", :authorizations
tree.add "/authorizations/:id", :authorization
tree.add "/applications", :applications
@ -127,7 +130,7 @@ module Radix
end
it "supports insertion of mixed routes out of order" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/user/repos", :my_repos
tree.add "/users/:user/repos", :user_repos
tree.add "/users/:user", :user
@ -148,9 +151,30 @@ module Radix
end
end
context "mixed payloads" do
it "allows node with different payloads" do
payload1 = Payload.new
payload2 = Payload.new
tree = Tree(Payload | Symbol).new
tree.add "/", :root
tree.add "/a", payload1
tree.add "/bc", payload2
# / (:root)
# +-bc (payload2)
# \-a (payload1)
tree.root.children.size.should eq(2)
tree.root.children[0].key.should eq("bc")
tree.root.children[0].payload.should eq(payload2)
tree.root.children[1].key.should eq("a")
tree.root.children[1].payload.should eq(payload1)
end
end
context "dealing with duplicates" do
it "does not allow same path be defined twice" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/abc", :abc
@ -164,7 +188,7 @@ module Radix
context "dealing with catch all and named parameters" do
it "prioritizes nodes correctly" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/*filepath", :all
tree.add "/products", :products
@ -193,7 +217,7 @@ module Radix
end
it "does not split named parameters across shared key" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/:category", :category
tree.add "/:category/:subcategory", :subcategory
@ -210,7 +234,7 @@ module Radix
end
it "does not allow different named parameters sharing same level" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/:post", :post
@ -224,7 +248,7 @@ module Radix
describe "#find" do
context "a single node" do
it "does not find when using different path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/about", :about
result = tree.find "/products"
@ -232,7 +256,7 @@ module Radix
end
it "finds when using matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/about", :about
result = tree.find "/about"
@ -243,7 +267,7 @@ module Radix
end
it "finds when using path with trailing slash" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/about", :about
result = tree.find "/about/"
@ -252,7 +276,7 @@ module Radix
end
it "finds when key has trailing slash" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/about/", :about
result = tree.find "/about"
@ -264,7 +288,7 @@ module Radix
context "nodes with shared parent" do
it "finds matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/abc", :abc
tree.add "/axyz", :axyz
@ -276,7 +300,7 @@ module Radix
end
it "finds matching path across parents" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/admin/users", :users
tree.add "/admin/products", :products
@ -292,7 +316,7 @@ module Radix
context "dealing with catch all" do
it "finds matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/*filepath", :all
tree.add "/about", :about
@ -304,7 +328,7 @@ module Radix
end
it "returns catch all in parameters" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/*filepath", :all
tree.add "/about", :about
@ -316,7 +340,7 @@ module Radix
end
it "returns optional catch all" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/search/*extra", :extra
@ -328,7 +352,7 @@ module Radix
end
it "does not find when catch all is not full match" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/search/public/*query", :search
@ -339,7 +363,7 @@ module Radix
context "dealing with named parameters" do
it "finds matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/products", :products
tree.add "/products/:id", :product
@ -352,7 +376,7 @@ module Radix
end
it "does not find partial matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/products", :products
tree.add "/products/:id/edit", :edit
@ -362,7 +386,7 @@ module Radix
end
it "returns named parameters in result" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/products", :products
tree.add "/products/:id", :product
@ -375,7 +399,7 @@ module Radix
end
it "returns unicode values in parameters" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/language/:name", :language
tree.add "/language/:name/about", :about
@ -389,7 +413,7 @@ module Radix
context "dealing with multiple named parameters" do
it "finds matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/:section/:page", :static_page
@ -400,7 +424,7 @@ module Radix
end
it "returns named parameters in result" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/:section/:page", :static_page
@ -417,7 +441,7 @@ module Radix
context "dealing with both catch all and named parameters" do
it "finds matching path" do
tree = Tree.new
tree = Tree(Symbol).new
tree.add "/", :root
tree.add "/*filepath", :all
tree.add "/products", :products

View file

@ -26,11 +26,11 @@ module Radix
# node.children.map &.priority
# # => [3, 2, 1]
# ```
class Node
getter key : String
getter? placeholder : Bool
property! payload
property children : Array(Node)
class Node(T)
getter key
getter? placeholder
property! payload : T | Nil
property children
# Returns the priority of the Node based on it's *key*
#
@ -42,16 +42,16 @@ module Radix
# * Any other type of key will receive priority based on its size.
#
# ```
# Node.new("a").priority
# Node(Nil).new("a").priority
# # => 1
#
# Node.new("abc").priority
# Node(Nil).new("abc").priority
# # => 3
#
# Node.new("*filepath").priority
# Node(Nil).new("*filepath").priority
# # => 0
#
# Node.new(":query").priority
# Node(Nil).new(":query").priority
# # => 1
# ```
getter priority : Int32
@ -59,16 +59,30 @@ module Radix
# Instantiate a Node
#
# - *key* - A `String` that represents this node.
# - *payload* - An Optional payload for this node.
def initialize(@key : String, @payload = nil, @placeholder = false)
@children = [] of Node
# - *payload* - An optional payload for this node.
#
# When *payload* is not supplied, ensure the type of the node is provided
# instead:
#
# ```
# # Good, node type is inferred from payload (Symbol)
# node = Node.new("/", :root)
#
# # Good, node type is now Int32 but payload is optional
# node = Node(Int32).new("/")
#
# # Error, node type cannot be inferred (compiler error)
# node = Node.new("/")
# ```
def initialize(@key : String, @payload : T? = nil, @placeholder = false)
@children = [] of Node(T)
@priority = compute_priority
end
# Changes current *key*
#
# ```
# node = Node.new("a")
# node = Node(Nil).new("a")
# node.key
# # => "a"
#
@ -80,7 +94,7 @@ module Radix
# This will also result in a new priority for the node.
#
# ```
# node = Node.new("a")
# node = Node(Nil).new("a")
# node.priority
# # => 1
#
@ -88,7 +102,7 @@ module Radix
# node.priority
# # => 6
# ```
def key=(@key : String)
def key=(@key)
@priority = compute_priority
end
@ -115,11 +129,11 @@ module Radix
# This ensures highest priority nodes are listed before others.
#
# ```
# root = Node.new("/")
# root.children << Node.new("*filepath") # node.priority => 0
# root.children << Node.new(":query") # node.priority => 1
# root.children << Node.new("a") # node.priority => 1
# root.children << Node.new("bc") # node.priority => 2
# root = Node(Nil).new("/")
# root.children << Node(Nil).new("*filepath") # node.priority => 0
# root.children << Node(Nil).new(":query") # node.priority => 1
# root.children << Node(Nil).new("a") # node.priority => 1
# root.children << Node(Nil).new("bc") # node.priority => 2
# root.sort!
#
# root.children.map &.priority

View file

@ -12,13 +12,15 @@ module Radix
#
# A Result is also used recursively by `Tree#find` when collecting extra
# information like *params*.
class Result
class Result(T)
@key : String?
getter params
getter! payload
getter! payload : T?
# :nodoc:
def initialize
@nodes = [] of Node
@nodes = [] of Node(T)
@params = {} of String => String
end
@ -26,26 +28,26 @@ module Radix
# the result.
#
# ```
# result = Result.new
# result = Result(Symbol).new
# result.found?
# # => false
#
# root = Node.new("/", :root)
# root = Node(Symbol).new("/", :root)
# result.use(root)
# result.found?
# # => true
# ```
def found? : Bool
def found?
payload? ? true : false
end
# Returns a String built based on the nodes used in the result
#
# ```
# node1 = Node.new("/", :root)
# node2 = Node.new("about", :about)
# node1 = Node(Symbol).new("/", :root)
# node2 = Node(Symbol).new("about", :about)
#
# result = Result.new
# result = Result(Symbol).new
# result.use node1
# result.use node2
#
@ -56,11 +58,11 @@ module Radix
# When no node has been used, returns an empty String.
#
# ```
# result = Result.new
# result = Result(Nil).new
# result.key
# # => ""
# ```
def key : String
def key
@key ||= begin
String.build { |io|
@nodes.each do |node|
@ -74,7 +76,7 @@ module Radix
#
# * Collect `Node` for future references.
# * Use *payload* if present.
def use(node : Node, payload = true)
def use(node : Node(T), payload = true)
# collect nodes
@nodes << node

View file

@ -12,7 +12,7 @@ module Radix
#
# You can associate a *payload* at insertion which will be return back
# at retrieval time.
class Tree
class Tree(T)
# :nodoc:
class DuplicateError < Exception
def initialize(path)
@ -30,10 +30,10 @@ module Radix
# Returns the root `Node` element of the Tree.
#
# On a new tree instance, this will be a placeholder.
getter root : Node
getter root : Node(T)
def initialize
@root = Node.new("", placeholder: true)
@root = Node(T).new("", placeholder: true)
end
# Inserts given *path* into the Tree
@ -98,19 +98,19 @@ module Radix
# # \-*filepath (:all)
# tree.add "/about", :about
# ```
def add(path : String, payload)
def add(path : String, payload : T)
root = @root
# replace placeholder with new node
if root.placeholder?
@root = Node.new(path, payload)
@root = Node(T).new(path, payload)
else
add path, payload, root
end
end
# :nodoc:
private def add(path : String, payload, node : Node)
private def add(path : String, payload : T, node : Node(T))
key_reader = Char::Reader.new(node.key)
path_reader = Char::Reader.new(path)
@ -151,7 +151,7 @@ module Radix
# if no existing child shared part of the key, add a new one
unless added
node.children << Node.new(new_key, payload)
node.children << Node(T).new(new_key, payload)
end
# adjust priorities
@ -174,7 +174,7 @@ module Radix
new_key = node.key.byte_slice(path_reader.pos)
swap_payload = node.payload? ? node.payload : nil
new_node = Node.new(new_key, swap_payload)
new_node = Node(T).new(new_key, swap_payload)
new_node.children.replace(node.children)
# clear payload and children (this is no longer and endpoint)
@ -189,7 +189,7 @@ module Radix
# determine if path still continues
if path_reader.pos < path.size
new_key = path.byte_slice(path_reader.pos)
node.children << Node.new(new_key, payload)
node.children << Node(T).new(new_key, payload)
node.sort!
# clear payload (no endpoint)
@ -223,7 +223,7 @@ module Radix
# # => :about
# ```
def find(path : String)
result = Result.new
result = Result(T).new
root = @root
# walk the tree from root (first time)