Fix ssl upgrade test failures

[seriyps]

There were 2 tests faling because of race-condition between user-generated message and inet driver message:

  1) smtp_socket:ssl_upgrade_test_/0: TCP connection can be upgraded to ssl                                                                                                                                                     
     Failure/Error: ?assertMatch({ sslsocket , _ , _ }, NewServerSocket)                                         
       expected: = { sslsocket , _ , _ }                                                                                                                                                                                        
            got: {inet_async,#Port<0.397>,1,{error,closed}}                                                                                                                                                                     
     %% eunit_proc.erl:325:in `eunit_proc:with_timeout/3`                                                                
     Output:  

  2) smtp_socket:ssl_upgrade_test_/0: SSL client connection can't be upgraded again                                                                                                                                             
     Failure/Error: {error,function_clause,                                                                                                                                                                                     
                        [{ssl,close,                                                                                                                                                                                            
                             [{inet_async,#Port<0.401>,1,{error,closed}}],                                                                                                                                                      
                             [{file,"ssl.erl"},{line,294}]},                                                                                                                                                                    
                         {eunit_test,run_testfun,1,                                                                                                                                                                             
                             [{file,"eunit_test.erl"},{line,71}]},                                               
                         {eunit_proc,run_test,1,                                                                                                                                                                                
                             [{file,"eunit_proc.erl"},{line,510}]},                                                                                                                                                             
                         {eunit_proc,with_timeout,3,                                                                     
                             [{file,"eunit_proc.erl"},{line,335}]},                                                                                                                                                             
                         {eunit_proc,handle_test,2,                                                                                                                                                                             
                             [{file,"eunit_proc.erl"},{line,493}]},                                                                                                                                                              
                         {eunit_proc,tests_inorder,3,                                                                                                                                                                           
                             [{file,"eunit_proc.erl"},{line,435}]},                                                                                                                                                             
                         {eunit_proc,with_timeout,3,                                                                                                                                                                             
                             [{file,"eunit_proc.erl"},{line,325}]},                                                                                                                                                             
                         {eunit_proc,run_group,2,                                                                                                                                                                               
                             [{file,"eunit_proc.erl"},{line,549}]}]} 

Now fixed by using selective receive.

Is there any chance Travis builds will be enabled for gen_smtp?

[arjan]

I still have two failures on this branch:

  1) socket:ssl_upgrade_test_/0: TCP connection can be upgraded to ssl
     Failure/Error: ?assertMatch({ sslsocket , _ , _ }, NewServerSocket)
       expected: = { sslsocket , _ , _ }
            got: {ssl_closed,
                     {sslsocket,
                         {gen_tcp,#Port<0.418>,tls_connection,<0.674.0>},
                         [<0.679.0>,<0.677.0>]}}=ERROR REPORT==== 28-May-2019::16:51:28.318775 ===

and:

  2) socket:ssl_upgrade_test_/0: SSL client connection can't be upgraded again
     Failure/Error: {error,function_clause,
                        [{ssl,close,
                             [{inet_async,#Port<0.438>,1,{error,closed}}],
                             [{file,"ssl.erl"},{line,596}]},
                         {eunit_test,run_testfun,1,
                             [{file,"eunit_test.erl"},{line,71}]},
                         {eunit_proc,run_test,1,
                             [{file,"eunit_proc.erl"},{line,510}]},
                         {eunit_proc,with_timeout,3,

Should this PR address these issues?

[arjan]

By the way, I'm +1 to enable Travis but the repo owner @Vagabond needs to enable this, IIRC.

[mworrell]

Indeed, only @Vagabond can enable Travis builds (or maybe add someone else as an extra owner)

[seriyps]

@arjan this is super strange, because these two are exactly the issues that were addressed in this PR. Are you 100% sure you are on the correct branch and that you don't have some build artifacts left from previous runs? Can you, please, try to remove _build directory before doing make test?

[arjan]

You are right, I'm sorry, I had to rebuild. Thanks for fixing this!