Export $HOME lookup to pkg/homedir

Signed-off-by: Ahmet Alp Balkan <ahmetb@microsoft.com>

homedir/MAINTAINERS

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+Ahmet Alp Balkan <ahmetalpbalkan@gmail.com> (@ahmetalpbalkan)

homedir/homedir.go

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+package homedir
+
+import (
+	"os"
+	"runtime"
+)
+
+// Get returns the home directory of the current user with the help of
+// environment variables depending on the target operating system.
+// Returned path should be used with "path/filepath" to form new paths.
+func Get() string {
+	if runtime.GOOS == "windows" {
+		return os.Getenv("USERPROFILE")
+	}
+	return os.Getenv("HOME")
+}

homedir/homedir_test.go

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+package homedir
+
+import (
+	"path/filepath"
+	"testing"
+)
+
+func TestGet(t *testing.T) {
+	home := Get()
+	if home == "" {
+		t.Fatal("returned home directory is empty")
+	}
+
+	if !filepath.IsAbs(home) {
+		t.Fatalf("returned path is not absolute: %s", home)
+	}
+}