Trying to run diff-bundle against a deployed model results in a runtime error:
$ juju --version
2.7.6-bionic-amd64
$ juju diff-bundle kubernetes_bundle.yaml
panic: runtime error: index out of range
goroutine 1 [running]:
github.com/juju/juju/vendor/github.com/juju/bundlechanges.relationFromEndpoints(0xc4208bd560, 0x2, 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/bundlechanges/diff.go:405 +0x206
github.com/juju/juju/vendor/github.com/juju/bundlechanges.(*differ).diffRelations(0xc420902360, 0xc420903020)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/bundlechanges/diff.go:197 +0xf4
github.com/juju/juju/vendor/github.com/juju/bundlechanges.(*differ).build(0xc420902360, 0xc420902360, 0x0, 0x3c91bc0)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/bundlechanges/diff.go:72 +0x5f
github.com/juju/juju/vendor/github.com/juju/bundlechanges.BuildDiff(0xc420a04c80, 0xc4200e95c0, 0x0, 0x3c91bc0, 0xc420902db0, 0x0, 0x0, 0x0)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/bundlechanges/diff.go:61 +0xab
github.com/juju/juju/cmd/juju/application.(*bundleDiffCommand).Run(0xc420b98240, 0xc4202beeb0, 0x0, 0x0)
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/juju/application/bundlediff.go:138 +0x1e4
github.com/juju/juju/cmd/modelcmd.(*modelCommandWrapper).Run(0xc420ac5ec0, 0xc4202beeb0, 0xc420ac5ec0, 0xc420902990)
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/modelcmd/modelcommand.go:608 +0x11c
github.com/juju/juju/cmd/modelcmd.(*baseCommandWrapper).Run(0xc42042f030, 0xc4202beeb0, 0x0, 0x0)
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/modelcmd/base.go:471 +0xab
github.com/juju/juju/vendor/github.com/juju/cmd.(*SuperCommand).Run(0xc4208e7900, 0xc4202beeb0, 0xc4202beeb0, 0x0)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/cmd/supercommand.go:516 +0x2cc
github.com/juju/juju/vendor/github.com/juju/cmd.Main(0x3cd9640, 0xc4208e7900, 0xc4202beeb0, 0xc42004c0d0, 0x2, 0x2, 0x326b860)
/build/juju/parts/juju/go/src/github.com/juju/juju/vendor/github.com/juju/cmd/cmd.go:379 +0x2d9
github.com/juju/juju/cmd/juju/commands.main.Run(0x385d9e0, 0xc42004c0c0, 0x3, 0x3, 0x0)
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/juju/commands/main.go:143 +0x1af
github.com/juju/juju/cmd/juju/commands.Main(0xc42004c0c0, 0x3, 0x3, 0xc4201120c0)
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/juju/commands/main.go:89 +0x4b
main.main()
/build/juju/parts/juju/go/src/github.com/juju/juju/cmd/juju/main.go:37 +0x8c
i also get this with 2.8.0-bionic-amd64
I'll include some bundles shortly