(session) compose session hash

[jackturnbull]

Currently seeing a compiler bug when attempting to compile with raven.cr. Although I'm not convinced entirely that this is an issue with action-controller, it does seem to be considered good practice to stick with composition rather than inheritence for this sort of stuff (crystal-lang/crystal#3238 (comment)).

The approach taken was effectively the same as amberframework/amber#930 which fixed the same issue within Amber.

Previously, the following:

require "raven"
require "action-controller"

Raven.configure do |settings|
  settings.async = true
end

Causes the compiler panic:

Error: you've found a bug in the Crystal compiler. Please open an issue, including source code that will allow us to reproduce the bug: https://github.com/crystal-lang/crystal/issues
Module validation failed: Function return type does not match operand type of return inst!
  ret %"(Array(AnyHash::JSONTypes::Value) | Bool | Float32 | Float64 | Hash(String | Symbol, AnyHash::JSONTypes::Value)+ | Int128 | Int16 | Int32 | Int64 | Int8 | JSON::Any | Set(AnyHash::JSONTypes::Value) | String | Symbol | Time | UInt128 | UInt16 | UInt32 | UInt64 | UInt8 | Nil)" %1, !dbg !21
 %"(Array(AnyHash::JSONTypes::Value) | Bool | Float32 | Float64 | Hash(String | Symbol, AnyHash::JSONTypes::Value) | Int128 | Int16 | Int32 | Int64 | Int8 | JSON::Any | Set(AnyHash::JSONTypes::Value) | String | Symbol | Time | UInt128 | UInt16 | UInt32 | UInt64 | UInt8 | Nil)" = type { i32, [3 x i64] } (Exception)
  from Crystal::CodeGenVisitor#finish:Nil
  from Crystal::Compiler#codegen<Crystal::Program, Crystal::ASTNode+, Array(Crystal::Compiler::Source), String>:(Tuple(Array(Crystal::Compiler::CompilationUnit), Array(String)) | Nil)
  from Crystal::Compiler#compile<Array(Crystal::Compiler::Source), String>:Crystal::Compiler::Result
  from Crystal::Command#run_command<Bool>:Nil
  from Crystal::Command#run:(Bool | Crystal::Compiler::Result | Nil)
  from main

[stakach]

I think we can remove this call to super

[jackturnbull]

Good catch!

[stakach]

Looks like a great solution - had no idea forward_missing_to was a feature

[stakach]

Can you remove the call to super and I'll merge

[jackturnbull]

Thanks for getting onto it so quickly! Didn't expect that at all :)