fix #479 by improving composed error backtraces and bump to 3.8.2

Big thanks to @robturtle and his original PR (#481) for steering me
toward this solution.

CHANGELOG.md

@@ -1,3 +1,9 @@
+# [3.8.2][] (2020-04-22)
+
+## Fixed
+
+- [479][] Composed interactions that throw errors now show a complete backtrace instead of ending at the `run!` of the outermost interaction.
+
 # [3.8.1][] (2020-04-04)
 
 ## Fixed
@@ -765,6 +771,7 @@ Example.run
 
 - Initial release.
 
+ [3.8.2]: https://github.com/AaronLasseigne/active_interaction/compare/v3.8.1...v3.8.2
  [3.8.1]: https://github.com/AaronLasseigne/active_interaction/compare/v3.8.0...v3.8.1
  [3.8.0]: https://github.com/AaronLasseigne/active_interaction/compare/v3.7.1...v3.8.0
  [3.7.1]: https://github.com/AaronLasseigne/active_interaction/compare/v3.7.0...v3.7.1
@@ -963,3 +970,4 @@ Example.run
  [#457]: https://github.com/AaronLasseigne/active_interaction/issues/457
  [#477]: https://github.com/AaronLasseigne/active_interaction/issues/477
  [#476]: https://github.com/AaronLasseigne/active_interaction/issues/476
+ [#479]: https://github.com/AaronLasseigne/active_interaction/issues/479

lib/active_interaction/concerns/runnable.rb

@@ -79,6 +79,7 @@ def run
  begin
  execute
  rescue Interrupt => interrupt
+ errors.backtrace = interrupt.errors.backtrace || interrupt.backtrace
  errors.merge!(interrupt.errors)
  end
  end
@@ -94,6 +95,7 @@ def run!
 
  e = InvalidInteractionError.new(errors.full_messages.join(', '))
  e.interaction = self
+ e.set_backtrace(errors.backtrace) if errors.backtrace
  raise e
  end
 

lib/active_interaction/errors.rb

@@ -92,6 +92,8 @@ def initialize(errors)
 
  # An extension that provides the ability to merge other errors into itself.
  class Errors < ActiveModel::Errors
+ attr_accessor :backtrace
+
  # Merge other errors into this one.
  #
  # @param other [Errors]

lib/active_interaction/version.rb

@@ -6,5 +6,5 @@ module ActiveInteraction
  # The version number.
  #
  # @return [Gem::Version]
- VERSION = Gem::Version.new('3.8.1')
+ VERSION = Gem::Version.new('3.8.2')
 end

spec/active_interaction/base_spec.rb

@@ -24,6 +24,12 @@ def execute
  class: Object,
  default: nil
 
+ # NOTE: the relative position between this method
+ # and the compose line should be preserved.
+ def self.composition_location
+ "#{__FILE__}:#{__LINE__ + 4}:in `execute'"
+ end
+
  def execute
  compose(AddInteraction, x: x, y: z)
  end
@@ -371,6 +377,15 @@ def execute
  expect(outcome.errors.details)
  .to eql(x: [{ error: :missing }], base: [{ error: 'Y is required' }])
  end
+
+ it 'has the correct backtrace' do
+ begin
+ described_class.run!(inputs)
+ rescue ActiveInteraction::InvalidInteractionError => e
+ expect(e.backtrace)
+ .to include(InterruptInteraction.composition_location)
+ end
+ end
  end
  end