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{Pointer, VoidPointer, uint8, DecodeStream, EncodeStream, Struct} = require '../'
should = require('chai').should()
concat = require 'concat-stream'
describe 'Pointer', ->
describe 'decode', ->
it 'should handle null pointers', ->
stream = new DecodeStream new Buffer [0]
pointer = new Pointer uint8, uint8
should.not.exist pointer.decode(stream, _startOffset: 50)
it 'should use local offsets from start of parent by default', ->
stream = new DecodeStream new Buffer [1, 53]
pointer = new Pointer uint8, uint8
pointer.decode(stream, _startOffset: 0).should.equal 53
it 'should support immediate offsets', ->
stream = new DecodeStream new Buffer [1, 53]
pointer = new Pointer uint8, uint8, type: 'immediate'
pointer.decode(stream).should.equal 53
it 'should support offsets relative to the parent', ->
stream = new DecodeStream new Buffer [0, 0, 1, 53]
stream.pos = 2
pointer = new Pointer uint8, uint8, type: 'parent'
pointer.decode(stream, parent: _startOffset: 2).should.equal 53
it 'should support global offsets', ->
stream = new DecodeStream new Buffer [1, 2, 4, 0, 0, 0, 53]
pointer = new Pointer uint8, uint8, type: 'global'
stream.pos = 2
pointer.decode(stream, parent: parent: _startOffset: 2).should.equal 53
it 'should support offsets relative to a property on the parent', ->
stream = new DecodeStream new Buffer [1, 0, 0, 0, 0, 53]
pointer = new Pointer uint8, uint8, relativeTo: 'parent.ptr'
pointer.decode(stream, _startOffset: 0, parent: ptr: 4).should.equal 53
it 'should support returning pointer if there is no decode type', ->
stream = new DecodeStream new Buffer [4]
pointer = new Pointer uint8, 'void'
pointer.decode(stream, _startOffset: 0).should.equal 4
it 'should support decoding pointers lazily', ->
stream = new DecodeStream new Buffer [1, 53]
struct = new Struct
ptr: new Pointer uint8, uint8, lazy: yes
res = struct.decode(stream)
Object.getOwnPropertyDescriptor(res, 'ptr').get.should.be.a('function')
Object.getOwnPropertyDescriptor(res, 'ptr').enumerable.should.equal(true)
res.ptr.should.equal 53
describe 'size', ->
it 'should add to local pointerSize', ->
pointer = new Pointer uint8, uint8
ctx = pointerSize: 0
pointer.size(10, ctx).should.equal 1
ctx.pointerSize.should.equal 1
it 'should add to immediate pointerSize', ->
pointer = new Pointer uint8, uint8, type: 'immediate'
ctx = pointerSize: 0
pointer.size(10, ctx).should.equal 1
ctx.pointerSize.should.equal 1
it 'should add to parent pointerSize', ->
pointer = new Pointer uint8, uint8, type: 'parent'
ctx = parent: pointerSize: 0
pointer.size(10, ctx).should.equal 1
ctx.parent.pointerSize.should.equal 1
it 'should add to global pointerSize', ->
pointer = new Pointer uint8, uint8, type: 'global'
ctx = parent: parent: parent: pointerSize: 0
pointer.size(10, ctx).should.equal 1
ctx.parent.parent.parent.pointerSize.should.equal 1
it 'should handle void pointers', ->
pointer = new Pointer uint8, 'void'
ctx = pointerSize: 0
pointer.size(new VoidPointer(uint8, 50), ctx).should.equal 1
ctx.pointerSize.should.equal 1
it 'should throw if no type and not a void pointer', ->
pointer = new Pointer uint8, 'void'
ctx = pointerSize: 0
should.throw ->
pointer.size(30, ctx).should.equal 1
it 'should return a fixed size without a value', ->
pointer = new Pointer uint8, uint8
pointer.size().should.equal 1
describe 'encode', ->
it 'should handle null pointers', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [0]
done()
ptr = new Pointer uint8, uint8
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 0,
pointers: []
ptr.encode(stream, null, ctx)
ctx.pointerSize.should.equal 0
stream.end()
it 'should handle local offsets', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [1]
done()
ptr = new Pointer uint8, uint8
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 1,
pointers: []
ptr.encode(stream, 10, ctx)
ctx.pointerOffset.should.equal 2
ctx.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should handle immediate offsets', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [0]
done()
ptr = new Pointer uint8, uint8, type: 'immediate'
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 1,
pointers: []
ptr.encode(stream, 10, ctx)
ctx.pointerOffset.should.equal 2
ctx.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should handle immediate offsets', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [0]
done()
ptr = new Pointer uint8, uint8, type: 'immediate'
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 1,
pointers: []
ptr.encode(stream, 10, ctx)
ctx.pointerOffset.should.equal 2
ctx.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should handle offsets relative to parent', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [2]
done()
ptr = new Pointer uint8, uint8, type: 'parent'
ctx =
parent:
pointerSize: 0,
startOffset: 3,
pointerOffset: 5,
pointers: []
ptr.encode(stream, 10, ctx)
ctx.parent.pointerOffset.should.equal 6
ctx.parent.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should handle global offsets', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [5]
done()
ptr = new Pointer uint8, uint8, type: 'global'
ctx =
parent:
parent:
parent:
pointerSize: 0,
startOffset: 3,
pointerOffset: 5,
pointers: []
ptr.encode(stream, 10, ctx)
ctx.parent.parent.parent.pointerOffset.should.equal 6
ctx.parent.parent.parent.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should support offsets relative to a property on the parent', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [6]
done()
ptr = new Pointer uint8, uint8, relativeTo: 'ptr'
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 10,
pointers: []
val:
ptr: 4
ptr.encode(stream, 10, ctx)
ctx.pointerOffset.should.equal 11
ctx.pointers.should.deep.equal [
{ type: uint8, val: 10, parent: ctx }
]
stream.end()
it 'should support void pointers', (done) ->
stream = new EncodeStream
stream.pipe concat (buf) ->
buf.should.deep.equal new Buffer [1]
done()
ptr = new Pointer uint8, 'void'
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 1,
pointers: []
ptr.encode(stream, new VoidPointer(uint8, 55), ctx)
ctx.pointerOffset.should.equal 2
ctx.pointers.should.deep.equal [
{ type: uint8, val: 55, parent: ctx }
]
stream.end()
it 'should throw if not a void pointer instance', ->
stream = new EncodeStream
ptr = new Pointer uint8, 'void'
ctx =
pointerSize: 0,
startOffset: 0,
pointerOffset: 1,
pointers: []
should.throw ->
ptr.encode(stream, 44, ctx)