Prerequisites

• make sure you're are using the latest version by seqkit version
• read the usage

Describe your issue

• describe the problem
• provide a reproducible example

Problem:

seqkit sana flags a sequence of length 1 and having the quality string of '+' as problematic for some reasons. This does not happen when the quality value is some other valid values which I have tried or when the sequence is longer than 1bp.

Example:

echo -e '@seq\nA\n+\n+\n' | seqkit sana
[INFO] File: - Discarded line: Invalid line states! 1: @seq
[INFO] File: - Discarded line: Invalid line states! 2: A
[INFO] File: - Discarded line: Invalid line states! 3: +
[INFO] File: - Discarded line: Invalid line states! 4: +
[INFO] File: - Pass records: 0 Discarded lines: 4

echo -e '@seq\nA\n+\n?\n' | seqkit sana
[INFO] File: - Pass records: 1 Discarded lines: 0
@seq
A
+
?

echo -e '@seq\nAA\n+\n++\n' | seqkit sana
[INFO] File: - Pass records: 1 Discarded lines: 0
@seq
AA
+
++