This test checks that gopls works with nested modules, including multiple
nested modules.

-- flags --
-min_go=go1.20

-- main.go --
package main

import "fmt"

func main() {
	fmt.Println(mainMsg) //@def("mainMsg", mainMsg)
	fmt.Println(undef) //@diag("undef", re"undefined|undeclared")
}
-- main2.go --
package main

const mainMsg = "main" //@loc(mainMsg, "mainMsg")

-- mod1/go.mod --
module golang.org/lsptests/mod1

go 1.20

-- mod1/a/a.go --
package a

import (
	"fmt"
	"golang.org/lsptests/mod1/b"
)

func _() {
	fmt.Println(b.Msg) //@def("Msg", Msg)
	fmt.Println(undef) //@diag("undef", re"undefined|undeclared")
}

-- mod1/a/tagged.go --
//go:build tag1

// golang/go#60776: verify that we get an accurate error about build tags
// here, rather than an inaccurate error suggesting to add a go.work
// file (which won't help).
package a //@diag(re`package (a)`, re`excluded due to its build tags`)

-- mod1/b/b.go --
package b

const Msg = "1" //@loc(Msg, "Msg")

-- mod2/go.mod --
module golang.org/lsptests/mod2

require golang.org/lsptests/mod1 v0.0.1

replace golang.org/lsptests/mod1 => ../mod1

go 1.20

-- mod2/c/c.go --
package c

import (
	"fmt"
	"golang.org/lsptests/mod1/b"
)

func _() {
	fmt.Println(b.Msg) //@def("Msg", Msg)
	fmt.Println(undef) //@diag("undef", re"undefined|undeclared")
}