# Create basic modules and work space.
env TESTGO_VERSION=go1.50
mkdir m1_22_0
go mod init -C m1_22_0
go mod edit -C m1_22_0 -go=1.22.0 -toolchain=go1.99.0
mkdir m1_22_1
go mod init -C m1_22_1
go mod edit -C m1_22_1 -go=1.22.1 -toolchain=go1.99.1
mkdir m1_24_rc0
go mod init -C m1_24_rc0
go mod edit -C m1_24_rc0 -go=1.24rc0 -toolchain=go1.99.2

go work init
grep '^go 1.50$' go.work
! grep toolchain go.work

# work use with older modules should leave go 1.50 in the go.work.
go work use ./m1_22_0
grep '^go 1.50$' go.work
! grep toolchain go.work

# work use with newer modules should bump go and toolchain,
# including updating to a newer toolchain as needed.
env TESTGO_VERSION=go1.21
env TESTGO_VERSION_SWITCH=switch
rm go.work
go work init
env GOTOOLCHAIN=local
! go work use ./m1_22_0
stderr '^go: m1_22_0'${/}'go.mod requires go >= 1.22.0 \(running go 1.21; GOTOOLCHAIN=local\)$'
env GOTOOLCHAIN=auto
go work use ./m1_22_0
stderr '^go: m1_22_0'${/}'go.mod requires go >= 1.22.0; switching to go1.22.9$'
grep '^go 1.22.0$' go.work
grep '^toolchain go1.22.9$' go.work

# work use with an even newer module should bump go again.
go work use ./m1_22_1
! stderr switching
grep '^go 1.22.1$' go.work
grep '^toolchain go1.22.9$' go.work  # unchanged

# work use with an even newer module should bump go and toolchain again.
env GOTOOLCHAIN=go1.22.9
! go work use ./m1_24_rc0
stderr '^go: m1_24_rc0'${/}'go.mod requires go >= 1.24rc0 \(running go 1.22.9; GOTOOLCHAIN=go1.22.9\)$'
env GOTOOLCHAIN=auto
go work use ./m1_24_rc0
stderr '^go: m1_24_rc0'${/}'go.mod requires go >= 1.24rc0; switching to go1.24rc1$'
grep '^go 1.24rc0$' go.work
grep '^toolchain go1.24rc1$' go.work