internal/lsp: fix LSP tests to be compatible with Go 1.10

Change golang/go#145697 added tests for diagnostics in the LSP implementation,
but these test did not work with Go 1.10. This change skips tests that
require Go 1.11.

Change-Id: I52bd2df484b5786395edac2c1c8592c83ac1aaa4
Reviewed-on: https://go-review.googlesource.com/c/147439
Reviewed-by: Ian Cottrell <iancottrell@google.com>

internal/lsp/diagnostics_test.go

@@ -2,6 +2,7 @@ package lsp
 
 import (
 	"go/token"
+	"path/filepath"
 	"reflect"
 	"sort"
 	"strings"
@@ -29,6 +30,7 @@ func testDiagnostics(t *testing.T, exporter packagestest.Exporter) {
 	exported := packagestest.Export(t, exporter, modules)
 	defer exported.Cleanup()
 
+	dirs := make(map[string]bool)
 	wants := make(map[string][]protocol.Diagnostic)
 	for _, module := range modules {
 		for fragment := range module.Files {
@@ -37,6 +39,7 @@ func testDiagnostics(t *testing.T, exporter packagestest.Exporter) {
 			}
 			filename := exporter.Filename(exported, module.Name, fragment)
 			wants[filename] = []protocol.Diagnostic{}
+			dirs[filepath.Dir(filename)] = true
 		}
 	}
 	err := exported.Expect(map[string]interface{}{
@@ -68,10 +71,20 @@ func testDiagnostics(t *testing.T, exporter packagestest.Exporter) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	var dirList []string
+	for dir := range dirs {
+		dirList = append(dirList, dir)
+	}
+	exported.Config.Mode = packages.LoadFiles
+	pkgs, err := packages.Load(exported.Config, dirList...)
+	if err != nil {
+		t.Fatal(err)
+	}
 	v := newView()
 	v.config = exported.Config
 	v.config.Mode = packages.LoadSyntax
-	for filename, want := range wants {
+	for _, pkg := range pkgs {
+		for _, filename := range pkg.GoFiles {
 			diagnostics, err := v.diagnostics(filenameToURI(filename))
 			if err != nil {
 				t.Fatal(err)
@@ -80,8 +93,10 @@ func testDiagnostics(t *testing.T, exporter packagestest.Exporter) {
 			sort.Slice(got, func(i int, j int) bool {
 				return got[i].Range.Start.Line < got[j].Range.Start.Line
 			})
+			want := wants[filename]
 			if equal := reflect.DeepEqual(want, got); !equal {
 				t.Errorf("diagnostics failed for %s: (expected: %v), (got: %v)", filename, want, got)
 			}
 		}
 	}
+}

internal/lsp/testdata/diagnostics/bad/bad.go

@@ -1,3 +1,5 @@
+// +build go1.11
+
 package bad
 
 func stuff() {

internal/lsp/testdata/diagnostics/bad/bad_util.go

@@ -1,3 +1,5 @@
+// +build go1.11
+
 package bad
 
 func random2(y int) int {