Do not remove password when new line is missing

If the password file doesn't end with a new line, the last line is
ignored because `read -r` will return a non-zero status, while still
setting the `$line` variable. Some implementations of pass, like
`gopass` do not create a password file ending with a new line.
Therefore, using `pass otp append` on these files will result in the
password being remove from the file.

To fix that, we ensure we insert the new line if it is missing.

I have added a test, but this is not enough to catch the problem
because `pass` will add the new line even when it is missing (for
example, using `echo -n | pass insert -e passfile` won't help to
trigger the bug).

1 files changed, 10 insertions, 0 deletions

diff --git a/test/append.t b/test/append.t
index 7f6d0af..a773e62 100755
--- a/test/append.t
+++ b/test/append.t
@@ -133,4 +133,14 @@ EOF
   [[ $("$PASS" show passfile) == "$expected" ]]
 '
 
+test_expect_success 'Keep original password' '
+  existing="foo bar baz"
+  uri="otpauth://totp/Example:alice@google.com?secret=JBSWY3DPEHPK3PXP&issuer=Foo"
+
+  test_pass_init &&
+  "$PASS" insert -e passfile <<< "$existing" &&
+  "$PASS" otp append -e passfile <<< "$uri" &&
+  [[ $("$PASS" show passfile | head -1) == "$existing" ]]
+'
+
 test_done