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).

2 files changed, 11 insertions, 1 deletions

diff --git a/otp.bash b/otp.bash
index 15bd012..c62501a 100755
--- a/otp.bash
+++ b/otp.bash
@@ -268,7 +268,7 @@ cmd_otp_append() {
   [[ -f $passfile ]] || die "Passfile not found"
 
   local existing contents=""
-  while IFS= read -r line; do
+  while IFS= read -r line || [ -n "$line" ]; do
     [[ -z "$existing" && "$line" == otpauth://* ]] && existing="$line"
     [[ -n "$contents" ]] && contents+=$'\n'
     contents+="$line"
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