3 files changed, 64 insertions, 9 deletions

diff --git a/lib/bundler/shared_helpers.rb b/lib/bundler/shared_helpers.rb
index f43e3301ef..405ade95dd 100644
--- a/lib/bundler/shared_helpers.rb
+++ b/lib/bundler/shared_helpers.rb
@@ -145,13 +145,6 @@ module Bundler
       Bundler.ui.warn message
     end
 
-    def trap(signal, override = false, &block)
-      prior = Signal.trap(signal) do
-        block.call
-        prior.call unless override
-      end
-    end
-
     def ensure_same_dependencies(spec, old_deps, new_deps)
       new_deps = new_deps.reject {|d| d.type == :development }
       old_deps = old_deps.reject {|d| d.type == :development }
diff --git a/lib/bundler/worker.rb b/lib/bundler/worker.rb
index 0380096523..5e4ee21c51 100644
--- a/lib/bundler/worker.rb
+++ b/lib/bundler/worker.rb
@@ -26,7 +26,7 @@ module Bundler
       @func = func
       @size = size
       @threads = nil
-      SharedHelpers.trap("INT") { abort_threads }
+      @previous_interrupt_handler = nil
     end
 
     # Enqueue a request to be executed in the worker pool
@@ -68,13 +68,16 @@ module Bundler
     # so as worker threads after retrieving it, shut themselves down
     def stop_threads
       return unless @threads
+
       @threads.each { @request_queue.enq POISON }
       @threads.each(&:join)
+
+      remove_interrupt_handler
+
       @threads = nil
     end
 
     def abort_threads
-      return unless @threads
       Bundler.ui.debug("\n#{caller.join("\n")}")
       @threads.each(&:exit)
       exit 1
@@ -94,11 +97,23 @@ module Bundler
         end
       end.compact
 
+      add_interrupt_handler unless @threads.empty?
+
       return if creation_errors.empty?
 
       message = "Failed to create threads for the #{name} worker: #{creation_errors.map(&:to_s).uniq.join(", ")}"
       raise ThreadCreationError, message if @threads.empty?
       Bundler.ui.info message
     end
+
+    def add_interrupt_handler
+      @previous_interrupt_handler = trap("INT") { abort_threads }
+    end
+
+    def remove_interrupt_handler
+      return unless @previous_interrupt_handler
+
+      trap "INT", @previous_interrupt_handler
+    end
   end
 end
diff --git a/spec/bundler/bundler/worker_spec.rb b/spec/bundler/bundler/worker_spec.rb
index 2e5642709d..e4ebbd2932 100644
--- a/spec/bundler/bundler/worker_spec.rb
+++ b/spec/bundler/bundler/worker_spec.rb
@@ -19,4 +19,51 @@ RSpec.describe Bundler::Worker do
       end
     end
   end
+
+  describe "handling interrupts" do
+    let(:status) do
+      pid = Process.fork do
+        $stderr.reopen File.new("/dev/null", "w")
+        Signal.trap "INT", previous_interrupt_handler
+        subject.enq "a"
+        subject.stop unless interrupt_before_stopping
+        Process.kill "INT", Process.pid
+      end
+
+      Process.wait2(pid).last
+    end
+
+    before do
+      skip "requires Process.fork" unless Process.respond_to?(:fork)
+    end
+
+    context "when interrupted before stopping" do
+      let(:interrupt_before_stopping) { true }
+      let(:previous_interrupt_handler) { ->(*) { exit 0 } }
+
+      it "aborts" do
+        expect(status.exitstatus).to eq(1)
+      end
+    end
+
+    context "when interrupted after stopping" do
+      let(:interrupt_before_stopping) { false }
+
+      context "when the previous interrupt handler was the default" do
+        let(:previous_interrupt_handler) { "DEFAULT" }
+
+        it "uses the default interrupt handler" do
+          expect(status).to be_signaled
+        end
+      end
+
+      context "when the previous interrupt handler was customized" do
+        let(:previous_interrupt_handler) { ->(*) { exit 42 } }
+
+        it "restores the custom interrupt handler after stopping" do
+          expect(status.exitstatus).to eq(42)
+        end
+      end
+    end
+  end
 end