git » log » commit dba4a5e

diff --git a/log.go b/log.go
index eaf3770..2c6a226 100644
--- a/log.go
+++ b/log.go
@@ -103,6 +103,13 @@ func New(w io.WriteCloser) *Logger {
 
 // NewFile creates a new Logger, which writes logs to the given file.
 func NewFile(path string) (*Logger, error) {
+	// Make path absolute, so Reopen continues to work if the program changes
+	// its working directory later.
+	path, err := filepath.Abs(path)
+	if err != nil {
+		return nil, err
+	}
+
 	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
 	if err != nil {
 		return nil, err
diff --git a/log_test.go b/log_test.go
index d6ed221..7d235cb 100644
--- a/log_test.go
+++ b/log_test.go
@@ -128,6 +128,20 @@ func TestReopen(t *testing.T) {
 	}
 	l.Infof("post reopen")
 	checkContentsMatch(t, "r", fname, `^_ log_test.go:....   post reopen\n`)
+
+	// NewFile with an absolute path should resolve it internally to a full
+	// one, so reopen can work.
+	l, err := NewFile("test-relative-file")
+	defer l.Close()
+	defer os.Remove("test-relative-file")
+
+	if err != nil {
+		t.Fatalf("failed to open file for testing: %v", err)
+	}
+	if l.fname[0] != '/' {
+		t.Fatalf("internal fname is not absolute: %q", l.fname)
+	}
+
 }
 
 type nopCloser struct {