passfile: directly read file instead of invoking cat

Allows better error handling, gets rid of the call to an
external program, and fixes https://github.com/rfjakob/gocryptfs/issues/278 .

1 files changed, 80 insertions, 0 deletions

diff --git a/internal/readpassword/passfile_test.go b/internal/readpassword/passfile_test.go
new file mode 100644
index 0000000..457170b
--- /dev/null
+++ b/internal/readpassword/passfile_test.go
@@ -0,0 +1,80 @@
+package readpassword
+
+import (
+	"os"
+	"os/exec"
+	"testing"
+)
+
+func TestPassfile(t *testing.T) {
+	testcases := []struct {
+		file string
+		want string
+	}{
+		{"mypassword.txt", "mypassword"},
+		{"mypassword_garbage.txt", "mypassword"},
+		{"mypassword_missing_newline.txt", "mypassword"},
+	}
+	for _, tc := range testcases {
+		pw := readPassFile("passfile_test_files/" + tc.file)
+		if string(pw) != tc.want {
+			t.Errorf("Wrong result: want=%q have=%q", tc.want, pw)
+		}
+	}
+}
+
+// readPassFile() should exit instead of returning an empty string.
+//
+// The TEST_SLAVE magic is explained at
+// https://talks.golang.org/2014/testing.slide#23 .
+func TestPassfileEmpty(t *testing.T) {
+	if os.Getenv("TEST_SLAVE") == "1" {
+		readPassFile("passfile_test_files/empty.txt")
+		return
+	}
+	cmd := exec.Command(os.Args[0], "-test.run=TestPassfileEmpty$")
+	cmd.Env = append(os.Environ(), "TEST_SLAVE=1")
+	err := cmd.Run()
+	if err != nil {
+		return
+	}
+	t.Fatal("should have exited")
+}
+
+// File containing just a newline.
+// readPassFile() should exit instead of returning an empty string.
+//
+// The TEST_SLAVE magic is explained at
+// https://talks.golang.org/2014/testing.slide#23 .
+func TestPassfileNewline(t *testing.T) {
+	if os.Getenv("TEST_SLAVE") == "1" {
+		readPassFile("passfile_test_files/newline.txt")
+		return
+	}
+	cmd := exec.Command(os.Args[0], "-test.run=TestPassfileEmpty$")
+	cmd.Env = append(os.Environ(), "TEST_SLAVE=1")
+	err := cmd.Run()
+	if err != nil {
+		return
+	}
+	t.Fatal("should have exited")
+}
+
+// File containing "\ngarbage".
+// readPassFile() should exit instead of returning an empty string.
+//
+// The TEST_SLAVE magic is explained at
+// https://talks.golang.org/2014/testing.slide#23 .
+func TestPassfileEmptyFirstLine(t *testing.T) {
+	if os.Getenv("TEST_SLAVE") == "1" {
+		readPassFile("passfile_test_files/empty_first_line.txt")
+		return
+	}
+	cmd := exec.Command(os.Args[0], "-test.run=TestPassfileEmptyFirstLine$")
+	cmd.Env = append(os.Environ(), "TEST_SLAVE=1")
+	err := cmd.Run()
+	if err != nil {
+		return
+	}
+	t.Fatal("should have exited")
+}