32 lines
1.1 KiB
Go
32 lines
1.1 KiB
Go
package structs
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import (
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"reflect"
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)
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var (
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// extendedTypes is a mapping of extended types to their extension function
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// TODO: the duplicates could be simplified by looking up the base type in the case of a pointer type in ConvertExt
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extendedTypes = map[reflect.Type]extendFunc{
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reflect.TypeOf(Node{}): nodeExt,
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reflect.TypeOf(&Node{}): nodeExt,
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}
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)
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// nodeExt ensures the node is sanitized and adds the legacy field .Drain back to encoded Node objects
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func nodeExt(v interface{}) interface{} {
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node := v.(*Node).Sanitize()
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// transform to a struct with inlined Node fields plus the Drain field
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// - using defined type (not an alias!) EmbeddedNode gives us free conversion to a distinct type
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// - distinct type prevents this encoding extension from being called recursively/infinitely on the embedding
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// - pointers mean the conversion function doesn't have to make a copy during conversion
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type EmbeddedNode Node
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return &struct {
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*EmbeddedNode
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Drain bool
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}{
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EmbeddedNode: (*EmbeddedNode)(node),
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Drain: node != nil && node.DrainStrategy != nil,
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}
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}
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