| 1 | ClassMap = require './class_map'
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| 2 |
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| 3 | name = (injectable) ->
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| 4 | if injectable.name? then injectable.name
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| 5 | else "'#{injectable}'"
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| 6 |
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| 7 | class Injector
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| 8 | constructor: (@binders...) ->
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| 9 | @_singletons = new ClassMap()
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| 10 | @_stack = []
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| 11 |
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| 12 | getInstance: (cls, args...) ->
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| 13 | @_stack.push(name(cls))
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| 14 |
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| 15 | try
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| 16 | for binder in @binders
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| 17 | for binding in binder.bindings
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| 18 | instance = @_resolve(cls, binding)
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| 19 | if instance? then return instance
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| 20 |
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| 21 | unless cls.prototype?
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| 22 | throw Error("Could not resolve: #{@_stack.join(' -> ')}")
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| 23 | @_createNew(cls, undefined, args...)
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| 24 |
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| 25 | finally
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| 26 | @_stack.pop()
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| 27 |
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| 28 | _createNew: (cls, scope, args...) ->
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| 29 | if cls is Injector then return this
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| 30 | singleton = @_singletons.get(cls)
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| 31 | if singleton? then return singleton
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| 32 |
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| 33 | ptype = ->
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| 34 | ptype.prototype = cls.prototype
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| 35 | instance = new ptype()
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| 36 | @_injectFields(cls.prototype, instance)
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| 37 | cls.apply(instance, args)
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| 38 |
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| 39 | if scope?.toUpperCase?() is 'SINGLETON' or cls.scope?.toUpperCase?() is 'SINGLETON'
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| 40 | @_singletons.set(cls, instance)
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| 41 |
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| 42 | instance
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| 43 |
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| 44 | _resolve: (cls, binding) ->
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| 45 | if binding.matches(cls)
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| 46 | defaultFactory = =>
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| 47 | @_createNew(binding.impl, binding.scope)
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| 48 | binding.create(defaultFactory)
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| 49 |
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| 50 | _injectFields: (ptype, instance) ->
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| 51 | for k, v of ptype
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| 52 | if v? and v._requiresInjection_
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| 53 | instance[k] = @getInstance(v.cls, v.args...)
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| 54 |
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| 55 | module.exports = Injector
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