1 files changed, 74 insertions, 0 deletions
diff --git a/libgo/go/cmd/go/internal/base/path.go b/libgo/go/cmd/go/internal/base/path.go
new file mode 100644
index 00000000000..4f12fa8c28c
--- /dev/null
+++ b/libgo/go/cmd/go/internal/base/path.go
@@ -0,0 +1,74 @@
+// 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 base
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+func getwd() string {
+	wd, err := os.Getwd()
+	if err != nil {
+		Fatalf("cannot determine current directory: %v", err)
+	}
+	return wd
+}
+
+var Cwd = getwd()
+
+// ShortPath returns an absolute or relative name for path, whatever is shorter.
+func ShortPath(path string) string {
+	if rel, err := filepath.Rel(Cwd, path); err == nil && len(rel) < len(path) {
+		return rel
+	}
+	return path
+}
+
+// RelPaths returns a copy of paths with absolute paths
+// made relative to the current directory if they would be shorter.
+func RelPaths(paths []string) []string {
+	var out []string
+	// TODO(rsc): Can this use Cwd from above?
+	pwd, _ := os.Getwd()
+	for _, p := range paths {
+		rel, err := filepath.Rel(pwd, p)
+		if err == nil && len(rel) < len(p) {
+			p = rel
+		}
+		out = append(out, p)
+	}
+	return out
+}
+
+// FilterDotUnderscoreFiles returns a slice containing all elements
+// of path whose base name doesn't begin with "." or "_".
+func FilterDotUnderscoreFiles(path []string) []string {
+	var out []string // lazily initialized
+	for i, p := range path {
+		base := filepath.Base(p)
+		if strings.HasPrefix(base, ".") || strings.HasPrefix(base, "_") {
+			if out == nil {
+				out = append(make([]string, 0, len(path)), path[:i]...)
+			}
+			continue
+		}
+		if out != nil {
+			out = append(out, p)
+		}
+	}
+	if out == nil {
+		return path
+	}
+	return out
+}
+
+// IsTestFile reports whether the source file is a set of tests and should therefore
+// be excluded from coverage analysis.
+func IsTestFile(file string) bool {
+	// We don't cover tests, only the code they test.
+	return strings.HasSuffix(file, "_test.go")
+}