Make TempfileReaper delete temp files if application raises an exception

Previously, tempfiles were only deleted if the exception occurred
when iterating over the body, not when raised during app.call.

Fixes rack#1679.

CHANGELOG.md

@@ -14,6 +14,7 @@ All notable changes to this project will be documented in this file. For info on
 
 ### Fixed
 
+- TempfileReaper now deletes temp files if application raises an exception. ([#1679](https://github.com/rack/rack/issues/1679), [@jeremyevans](https://github.com/jeremyevans))
 - Fix using Rack::Session::Cookie with coder: Rack::Session::Cookie::Base64::{JSON,Zip}. ([#1666](https://github.com/rack/rack/issues/1666), [@jeremyevans](https://github.com/jeremyevans))
 - Avoid NoMethodError when accessing Rack::Session::Cookie without requiring delegate first. ([#1610](https://github.com/rack/rack/issues/1610), [@onigra](https://github.com/onigra))
 - Handle cookies with values that end in '=' ([#1645](https://github.com/rack/rack/pull/1645), [@lukaso](https://github.com/lukaso))

lib/rack/tempfile_reaper.rb

@@ -12,7 +12,14 @@ def initialize(app)
 
     def call(env)
       env[RACK_TEMPFILES] ||= []
-      status, headers, body = @app.call(env)
+
+      begin
+        status, headers, body = @app.call(env)
+      rescue Exception
+        env[RACK_TEMPFILES].each(&:close!) unless env[RACK_TEMPFILES].nil?
+        raise
+      end
+
       body_proxy = BodyProxy.new(body) do
         env[RACK_TEMPFILES].each(&:close!) unless env[RACK_TEMPFILES].nil?
       end

test/spec_tempfile_reaper.rb

@@ -30,6 +30,24 @@ def call(app)
     response[0].must_equal 200
   end
 
+  it 'close env[rack.tempfiles] when app raises an error' do
+    tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
+    @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]
+    app = lambda { |_| raise 'foo' }
+    proc{call(app)}.must_raise RuntimeError
+    tempfile1.closed.must_equal true
+    tempfile2.closed.must_equal true
+  end
+
+  it 'close env[rack.tempfiles] when app raises an non-StandardError' do
+    tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
+    @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]
+    app = lambda { |_| raise LoadError, 'foo' }
+    proc{call(app)}.must_raise LoadError
+    tempfile1.closed.must_equal true
+    tempfile2.closed.must_equal true
+  end
+
   it 'close env[rack.tempfiles] when body is closed' do
     tempfile1, tempfile2 = MockTempfile.new, MockTempfile.new
     @env['rack.tempfiles'] = [ tempfile1, tempfile2 ]