Initial Bitbucket→GitHub migration commit, based on release v2.0.0.

user.go

@@ -0,0 +1,43 @@
+/*
+	Copyright © 2014–2019 Thomas Michael Edwards. All rights reserved.
+	Use of this source code is governed by a Simplified BSD License which
+	can be found in the LICENSE file.
+*/
+
+package main
+
+import (
+	"errors"
+	"os"
+	"os/user"
+	"runtime"
+)
+
+func userHomeDir() (string, error) {
+	// Prefer the user's `HOME` environment variable.
+	if homeDir := os.Getenv("HOME"); homeDir != "" {
+		return homeDir, nil
+	}
+
+	// Elsewise, use the user's `.HomeDir` info.
+	if curUser, err := user.Current(); err == nil && curUser.HomeDir != "" {
+		return curUser.HomeDir, nil
+	}
+
+	// Failovers for Windows, though they should be unnecessary in Go ≥v1.7.
+	if runtime.GOOS == "windows" {
+		// Prefer the user's `USERPROFILE` environment variable.
+		if homeDir := os.Getenv("USERPROFILE"); homeDir != "" {
+			return homeDir, nil
+		}
+
+		// Elsewise, use the user's `HOMEDRIVE` and `HOMEPATH` environment variables.
+		homeDrive := os.Getenv("HOMEDRIVE")
+		homePath := os.Getenv("HOMEPATH")
+		if homeDrive != "" && homePath != "" {
+			return homeDrive + homePath, nil
+		}
+	}
+
+	return "", errors.New("Cannot find user home directory.")
+}