If the developer tests his own code then there is a danger that he will pass his misunderstanding of specification.
Anyway in the safety critical environments the one who wrote the code does not do the testing. Testing is done by developers.Of course. On that point I will agree to disagree because the Tech Lead on the project I worked on would never do the testing. Phil the contractor was doing unit tests from the code not from specification, all he was doing was testing the compiler or the VMS emulator ( dumb terminal client server). He was never seen again. The safety critical people take testing very seriously. I waited for "phil the contractor" the next day to give me the specification. The manager said don't worry about him he won't be coming. I went from testing to maintenance, ladder up the project lifecycle. Tests are also done on hardware electrical rigs , simulating feed to sensors. The fuel management system was setup up inside fuel tanker and driven across the city, simulating the movement of an aircraft. Up and down hills etc. Apart from live testing which would be fourth type of testing. Coding in that environment is merely 10%-15 % of project resources. Should be part on any project. I have come across baffoons who want to dive into coding without even going through the team analysis and design stage. The ones who don't want to learn anything new are the worst like the "phil the visual Basic programmer." The tech lead who abandoned the project when I told him everything is going server side. That was not the only buffoonary he displayed because he could not wait to dive into coding. On Tue, 3 Dec 2019, 12:33 Dave Newton, <davelnew...@gmail.com> wrote: > On Tue, Dec 3, 2019 at 07:04 Zahid Rahman <zahidr1...@gmail.com> wrote: > > > test from specification not from code and testing MUST not > > to be done by the person who wrote the code as suggested in a book I read > > recently. > > > Testing is multi-tiered just like the rest of large applications. > Developers are in a unique position to do more in-depth testing than pure > black-box testing would allow, including testing interop layers invisible > to, say, QA at the front-end. > > There's a reason there are different names for different types of testing, > and ideally, there are multiple layers of testing, performed across dev > groups. > > Dave > > -- > em: davelnew...@gmail.com > mo: 908-380-8699 > tw: @dave_newton <https://twitter.com/dave_newton> > li: dave-newton <https://www.linkedin.com/in/dave-newton/> > gh: davelnewton <https://github.com/davelnewton> > so: Dave Newton <http://stackoverflow.com/users/438992/dave-newton> > bl[0]: Bucky Bits <http://buckybits.blogspot.com/> > bl[1]: Maker's End Blog <https://blog.makersend.com> > sk: davelnewton_skype >