[lobster_johnson]

Testing and package management aren't mutually exclusive. If you're in a monorepo, all your code evolves in lockstep. A core tenet of versioned package management is to get reproducible builds that only need to break once you choose to evolve forward in time (i.e. upgrade).

Historically, most languages (C, C++, pre-Maven Java) haven't had package management at all, and so dependencies have typically been managed by vendoring the code (or JAR files). JAR files worked okay, but vendoring incurs maintenance overhead that isn't acceptable in today's environment. git submodules are theoretically a solution, but also high-maintenance.

[skybrian]

Yes, you are right. And I believe vgo is supposed to guarantee reproducible builds just like other package systems.

However, when you upgrade a dependency, it's still possible that you're using a particular combination of library versions that have never been tested before.

Some incompatibilities can be prevented by looking at version constraints. But you're not left with no error detection if the package system fails to detect an incompatibility; in the end, what matters is that the code compiles and the tests pass.

[oceanswave]

This methodology places way too much emphasis on the breadth of the tests into a test centric view— say you had a dep that had an SSL vulnerability - most of the time you’re not going to be checking for this type of thing at the level of your app, and doing so - but you bet you need to ensure that you are using the version of the dep that has the vulnerability fixed