go mod why golang.org/x/text/language
cmp stdout why-language.txt

# why a module?
go mod why -m golang.org...
cmp stdout why-text-module.txt

# why a package used only in tests?
go mod why rsc.io/testonly
cmp stdout why-testonly.txt

# why a module used only in a test of a dependency?
go mod why -m rsc.io/testonly
cmp stdout why-testonly.txt

# test package not needed
go mod why golang.org/x/text/unused

# The whole enchilada.
go tool covdata textfmt -i=$WORK/covdata -o=$WORK/covdata/out.txt
grep 'mode: set' $WORK/covdata/out.txt
grep 'mod.example/main/main.go:' $WORK/covdata/out.txt
grep 'mod.example/sub/sub.go:' $WORK/covdata/out.txt
grep 'rsc.io' $WORK/covdata/out.txt
grep 'bufio/bufio.go:' $WORK/covdata/out.txt

# Use the covdata tool to select a specific set of module paths
mkdir $WORK/covdata2

go work vendor
stderr 'go: no dependencies to vendor'
! exists vendor/modules.txt
! go list .
stderr 'go: no modules were found in the current workspace'
mkdir vendor
mv bad_modules.txt vendor/modules.txt
! go list .
stderr 'go: no modules were found in the current workspace'

-- bad_modules.txt --
# a/module
a/package
-- go.work --

cp go.work.firsterrlisted.txt go.work
! go list
stderr '^go.work:1: unknown godebug "baz"$'

-- foo/go.mod --
module example.com/foo
-- go.work.repeated.txt --


use foo
use foo
-- go.work.badgodebug.txt --


godebug foo=1
-- go.work.unparsable.txt --




notadirective
-- go.work.firstlineerr.txt --
godebug bar=1
-- go.work.firsterrlisted.txt --
godebug baz=1

cp stdout tool-json-broken.txt

[short] stop


# Check against the real cmd/dist as the source of truth.

env GOROOT=$TESTGO_GOROOT
go build -o dist.exe cmd/dist

exec ./dist.exe list
cmp stdout tool.txt

exec ./dist.exe list -v
cmp stdout tool-v.txt

exec ./dist.exe list -broken
cmp stdout tool-broken.txt

exec ./dist.exe list -json
cmp stdout tool-json.txt

exec ./dist.exe list -json -broken

# https://golang.org/issue/36876: As of Go 1.17, vendor/modules.txt should
# indicate the language version used by each dependency.

[short] skip

# Control case: without a vendor directory, need117 builds and bad114 doesn't.

go build example.net/need117
! go build example.net/bad114
stderr '^bad114[/\\]bad114.go:15:2: duplicate method .?Y.?( .*)?$'


# With a vendor/modules.txt lacking language versions, the world is topsy-turvy,

go test -run=ReadTestdata .
! stdout '(cached)'
go test -run=ReadTestdata .
stdout '(cached)'
cp testdata/bar.txt testdata/foo.txt
go test -run=ReadTestdata .
! stdout '(cached)'

-- go.mod --
module golang.org/issue/29111/foo

-- foo.go --
package foo

-- testdata/foo.txt --
foo
-- testdata/bar.txt --
bar

-- foo_test.go --
package foo_test

import (
	"os"
	"path/filepath"
	"testing"
)

# between the go.mod file and vendor/modules.txt.
# A 'go 1.13' vendor/modules.txt file is not usually sufficient
# to pass those checks.
go mod edit -go=1.14

! go list -f {{.Dir}} -tags tools all
stderr '^go: inconsistent vendoring in '$WORK[/\\]auto':$'
stderr '^\texample.com/printversion@v1.0.0: is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt'

# Get errors from a go test into stderr.txt
! go test coverbad
stderr 'p\.go:4:2' # look for error at coverbad/p.go:4
[cgo] stderr 'p1\.go:6:2' # look for error at coverbad/p.go:6
! stderr $WORK # make sure temporary directory isn't in error

cp stderr $WORK/stderr.txt

# Get errors from coverage into stderr2.txt
! go test -cover coverbad
cp stderr $WORK/stderr2.txt

wait # for go run above

	# of a directory within the module cache.
cp $WORK/extraneous.txt $GOPATH/pkg/mod/example.com/printversion@v0.1.0/extraneous_file.go
go clean -modcache


! go install -unknownflag -tags -modcacherw example.com/printversion@v0.1.0
stderr '^flag provided but not defined: -unknownflag$'
cp $WORK/extraneous.txt $GOPATH/pkg/mod/example.com/printversion@v0.1.0/extraneous_file.go
go clean -modcache