Ignore dot-prefixed files and subdirs when scanning packages

internal/gps/_testdata/src/dotgodir/foo.go/foo.go

@@ -0,0 +1,12 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package foo
+
+import "sort"
+
+var _ = sort.Strings
+
+// yes, this is dumb, don't use ".go" in your directory names
+// See https://github.com/golang/dep/issues/550 for more information

internal/gps/pkgtree/pkgtree.go

@@ -199,10 +199,17 @@ func fillPackage(p *build.Package) error {
 	var testImports []string
 	var imports []string
 	for _, file := range gofiles {
-		// Skip underscore-led files, in keeping with the rest of the toolchain.
-		if filepath.Base(file)[0] == '_' {
+		// Skip underscore-led or dot-led files, in keeping with the rest of the toolchain.
+		bPrefix := filepath.Base(file)[0]
+		if bPrefix == '_' || bPrefix == '.' {
 			continue
 		}
+
+		// Skip any directories that happened to get caught by glob
+		if stat, err := os.Stat(file); err == nil && stat.IsDir() {
+			continue
+		}
+
 		pf, err := parser.ParseFile(token.NewFileSet(), file, nil, parser.ImportsOnly|parser.ParseComments)
 		if err != nil {
 			if os.IsPermission(err) {

internal/gps/pkgtree/pkgtree_test.go

@@ -1280,6 +1280,28 @@ func TestListPackages(t *testing.T) {
 				},
 			},
 		},
+		"skip directories starting with '.'": {
+			fileRoot:   j("dotgodir"),
+			importRoot: "dotgodir",
+			out: PackageTree{
+				ImportRoot: "dotgodir",
+				Packages: map[string]PackageOrErr{
+					"dotgodir": {
+						P: Package{
+							ImportPath: "dotgodir",
+							Imports:    []string{},
+						},
+					},
+					"dotgodir/foo.go": {
+						P: Package{
+							ImportPath: "dotgodir/foo.go",
+							Name:       "foo",
+							Imports:    []string{"sort"},
+						},
+					},
+				},
+			},
+		},
 	}
 
 	for name, fix := range table {