dep panic on ctrl+c (new one)

[Civil]

dep ensure
^CSignal received: waiting for 1 ops to complete...
panic: canary - shouldn't be possible this SourceMgr has been released, its methods can no longer be called

goroutine 1 [running]:
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*solver).unselectLast(0xc42023e7e0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	/root/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/solver.go:1189 +0x863
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*solver).backtrack(0xc42023e7e0, 0xc420183200)
	/root/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/solver.go:942 +0x166
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*solver).solve(0xc42023e7e0, 0x0, 0x0, 0x20)
	/root/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/solver.go:409 +0x787
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*solver).Solve(0xc42023e7e0, 0x2d, 0xa67140, 0xab51f8, 0xc420016011)
	/root/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/solver.go:355 +0xab
main.(*ensureCommand).Run(0xc42013d560, 0xc420142e10, 0xc42000c160, 0x0, 0x0, 0x0, 0x0)
	/root/go/src/github.com/golang/dep/cmd/dep/ensure.go:145 +0x358
main.main()
	/root/go/src/github.com/golang/dep/cmd/dep/main.go:125 +0x6df
Makefile:21: recipe for target 'dep' failed
make: *** [dep] Error 2

This happens if I hit 'ctrl + c' almost immediately after starting 'dep ensure'.

I've tried to update to current master, but no luck.

[sdboyer]

Hmm - I changed a lot in that update with respect to lifecycle management within subcomponents of the SourceManager, but punted a bit on the overall lifecycle management (e.g., signals) with the expectation that we'd be coming to it in sdboyer/gps#159. Guess it needs some love sooner than that 😄

I'll have a look soon - thanks for posting the issue!

[sdboyer]

this is no longer an issue - or at least, not the panic. we still have error handling to deal with, but the primary focal point of this ticket is addressed.