1 files changed, 66 insertions, 20 deletions

diff --git a/activesupport/test/rescuable_test.rb b/activesupport/test/rescuable_test.rb
index bd43ad0797..b1b8a25c5b 100644
--- a/activesupport/test/rescuable_test.rb
+++ b/activesupport/test/rescuable_test.rb
@@ -1,9 +1,8 @@
-require 'abstract_unit'
+# frozen_string_literal: true
 
-class WraithAttack < StandardError
-end
+require "abstract_unit"
 
-class NuclearExplosion < StandardError
+class WraithAttack < StandardError
 end
 
 class MadRonon < StandardError
@@ -19,16 +18,20 @@ module WeirdError
 end
 
 class Stargate
+  # Nest this so the 'NuclearExplosion' handler needs a lexical const_get
+  # to find it.
+  class NuclearExplosion < StandardError; end
+
   attr_accessor :result
 
   include ActiveSupport::Rescuable
 
-  rescue_from WraithAttack, :with => :sos_first
+  rescue_from WraithAttack, with: :sos_first
 
-  rescue_from WraithAttack, :with => :sos
+  rescue_from WraithAttack, with: :sos
 
-  rescue_from 'NuclearExplosion' do
-    @result = 'alldead'
+  rescue_from "NuclearExplosion" do
+    @result = "alldead"
   end
 
   rescue_from MadRonon do |e|
@@ -36,13 +39,15 @@ class Stargate
   end
 
   rescue_from WeirdError do
-    @result = 'weird'
+    @result = "weird"
   end
 
   def dispatch(method)
     send(method)
   rescue Exception => e
-    rescue_with_handler(e)
+    unless rescue_with_handler(e)
+      @result = "unhandled"
+    end
   end
 
   def attack
@@ -57,6 +62,34 @@ class Stargate
     raise MadRonon.new("dex")
   end
 
+  def crash
+    raise "unhandled RuntimeError"
+  end
+
+  def looped_crash
+    ex1 = StandardError.new("error 1")
+    ex2 = StandardError.new("error 2")
+    begin
+      begin
+        raise ex1
+      rescue
+        # sets the cause on ex2 to be ex1
+        raise ex2
+      end
+    rescue
+      # sets the cause on ex1 to be ex2
+      raise ex1
+    end
+  end
+
+  def fall_back_to_cause
+    # This exception is the cause and has a handler.
+    ronanize
+  rescue
+    # This is the exception we'll handle that doesn't have a cause.
+    raise "unhandled RuntimeError with a handleable cause"
+  end
+
   def weird
     StandardError.new.tap do |exc|
       def exc.weird?
@@ -68,13 +101,12 @@ class Stargate
   end
 
   def sos
-    @result = 'killed'
+    @result = "killed"
   end
 
   def sos_first
-    @result = 'sos_first'
+    @result = "sos_first"
   end
-
 end
 
 class CoolStargate < Stargate
@@ -82,14 +114,13 @@ class CoolStargate < Stargate
 
   include ActiveSupport::Rescuable
 
-  rescue_from CoolError, :with => :sos_cool_error
+  rescue_from CoolError, with: :sos_cool_error
 
   def sos_cool_error
-    @result = 'sos_cool_error'
+    @result = "sos_cool_error"
   end
 end
 
-
 class RescuableTest < ActiveSupport::TestCase
   def setup
     @stargate = Stargate.new
@@ -98,22 +129,22 @@ class RescuableTest < ActiveSupport::TestCase
 
   def test_rescue_from_with_method
     @stargate.dispatch :attack
-    assert_equal 'killed', @stargate.result
+    assert_equal "killed", @stargate.result
   end
 
   def test_rescue_from_with_block
     @stargate.dispatch :nuke
-    assert_equal 'alldead', @stargate.result
+    assert_equal "alldead", @stargate.result
   end
 
   def test_rescue_from_with_block_with_args
     @stargate.dispatch :ronanize
-    assert_equal 'dex', @stargate.result
+    assert_equal "dex", @stargate.result
   end
 
   def test_rescue_from_error_dispatchers_with_case_operator
     @stargate.dispatch :weird
-    assert_equal 'weird', @stargate.result
+    assert_equal "weird", @stargate.result
   end
 
   def test_rescues_defined_later_are_added_at_end_of_the_rescue_handlers_array
@@ -127,4 +158,19 @@ class RescuableTest < ActiveSupport::TestCase
     result = @cool_stargate.send(:rescue_handlers).collect(&:first)
     assert_equal expected, result
   end
+
+  def test_rescue_falls_back_to_exception_cause
+    @stargate.dispatch :fall_back_to_cause
+    assert_equal "dex", @stargate.result
+  end
+
+  def test_unhandled_exceptions
+    @stargate.dispatch(:crash)
+    assert_equal "unhandled", @stargate.result
+  end
+
+  def test_rescue_handles_loops_in_exception_cause_chain
+    @stargate.dispatch :looped_crash
+    assert_equal "unhandled", @stargate.result
+  end
 end