--- /dev/null
+package regtest
+
+import (
+ "testing"
+
+ "golang.org/x/tools/internal/lsp"
+ "golang.org/x/tools/internal/testenv"
+)
+
+const basicProxy = `
+-- golang.org/x/hello@v1.2.3/go.mod --
+module golang.org/x/hello
+
+go 1.14
+-- golang.org/x/hello@v1.2.3/hi/hi.go --
+package hi
+
+var Goodbye error
+`
+
+func TestInconsistentVendoring(t *testing.T) {
+ testenv.NeedsGo1Point(t, 14)
+ const pkgThatUsesVendoring = `
+-- go.mod --
+module mod.com
+
+go 1.14
+
+require golang.org/x/hello v1.2.3
+-- vendor/modules.txt --
+-- a/a1.go --
+package a
+
+import "golang.org/x/hello/hi"
+
+func _() {
+ _ = hi.Goodbye
+ var q int // hardcode a diagnostic
+}
+`
+ // TODO(rstambler): Remove this when golang/go#41819 is resolved.
+ withOptions(
+ WithModes(WithoutExperiments),
+ WithProxyFiles(basicProxy),
+ ).run(t, pkgThatUsesVendoring, func(t *testing.T, env *Env) {
+ env.OpenFile("a/a1.go")
+ env.Await(
+ // The editor should pop up a message suggesting that the user
+ // run `go mod vendor`, along with a button to do so.
+ // By default, the fake editor always accepts such suggestions,
+ // so once we see the request, we can assume that `go mod vendor`
+ // will be executed.
+ OnceMet(
+ CompletedWork(lsp.DiagnosticWorkTitle(lsp.FromDidOpen), 1),
+ ShowMessageRequest("go mod vendor"),
+ ),
+ )
+ env.CheckForFileChanges()
+ env.Await(
+ OnceMet(
+ CompletedWork(lsp.DiagnosticWorkTitle(lsp.FromDidChangeWatchedFiles), 1),
+ DiagnosticAt("a/a1.go", 6, 5),
+ ),
+ )
+ })
+}