How to ignore multiple lines of code in the same file type using gitattribute and git config?

Question

As an extension of this post: Can git ignore a specific line?, I am trying to ignore multiple lines in the same file type.

Is there a way to either;

• set multiple filters to the same .gitattributes filter for the same file or file types? (like below) OR

*.rs filter=filterA
*.rs filter=filterB

 // to something like
*.rs filter=filterA + filterB

• add multiple rules to the same filter in .git/config? (like below)

[filter "filterA"]
    clean = sed "/abc/d"
[filter "filterB"]
    clean = sed "/def/d"

 // to something like
[filter "filterC"]
    clean = sed "/abc/d"
    clean = sed "/def/d"

The above causes the last filter in .gitattributes to overwrite the changes made from the first filter. I have also attempted something like clean = sed "/abc*def/d", but this did not work.

Answer 1

If you want to ignore entire lines my advice is to use grep -v instead of sed //d. The answers at the linked question use sed because they hide only parts of lines, a task for which sed is exactly suitable.

So 1st lets rewrite your two simple filters:

[filter "filterA"]
    clean = grep -v "abc"
[filter "filterB"]
    clean = grep -v "def"

Please be warned that if your placeholders abc and def contain regular expression metacharacters you need to escape them using backslash. Like \* — grep interprets this as a literal asterisk while * is a metacharacter. See man grep.

Now to the more complex filter: combine the two expressions into one complex regular expression:

[filter "filterC"]
    clean = grep -v "abc\|def"

\| separates branches in regular expressions in basic (default) grep syntax. In case of extended RE the syntax is

[filter "filterC"]
    clean = grep -Ev "abc|def"