Should the extension be stripped in $2 of file.a.b.do?

[mle...@gmail.com]

Hi!

The documentation (https://github.com/apenwarr/redo/blob/master/docs/redo.md) says:

The three arguments passed to the .do script are:

• $1: the target name (eg. mytarget.a.b)
• $2: the basename of the target, minus its extension (eg. mytarget)
• $3: a temporary filename that the .do script should write its output to.

 

However, this is not always what I get. If I have a do file whose name does not start with "default...", I observe a different behaviour, the extension is not stripped

file        do-file           $2
----------- ----------------  ----------
file.a.b.c  file.a.b.c.do     file.a.b.c
file.a.b.c  default.a.b.c.do  file
file.a.b.c  default.b.c.do    file.a
file.a.b.c  default.c.do      file.a.b
file.a.b.c  default.do        file.a.b.c

Below this mail is example code to test this. I don't see the reason for this behaviour. Is it a bug or a feature? Should the documentation be updated?

Best,

Moritz

Example:

cat >default.do <<EOF
echo "\$0" "\$2" >&2
EOF
redo file.a.b.c

mv default.do default.c.do
redo file.a.b.c

mv default.c.do default.b.c.do
redo file.a.b.c

mv default.b.c.do default.a.b.c.do
redo file.a.b.c

mv default.a.b.c.do file.a.b.c.do
redo file.a.b.c


rm file.a.b.c.do

[Wolfgang Faust]

I suspect this behavior is because, with a target that matches the entire filename, redo does not know which part of the filename to consider the extension. For example, when I run "redo example.com.meta.json.gz", redo finds "default.meta.json.gz.do" and passes it "$2=example.com" (so that I can write "$2.info.txt" and get the corresponding file). But without the context provided by the .do file, it's ambiguous which parts of that filename are "the basename" and which parts are extensions. I could, for example, also have a "default.gz.do", and if redo matched that it would set "$2=example.com.meta.json" instead, so I could write `gzip -c "$2" > "$3"` and achieve the desired result.

That said, I agree that the documentation here is lacking on details. I've also found myself confused on the expected behavior of $2 when the .do file is in a different directory from the target—the manual explains what happens in this situation to $1 and $3, but unfortunately makes no mention of $2.

[spacefro...@meterriblecrew.net]

The behaviour is exactly as specified.

Look at default.do as follows:
- the string 'default' means wildcard
- the suffix .do is not part of the match
- any string starting with a . (dot) is a legal suffix to the string 'default'

The suffix is stripped from $2. It becomes clear now, that in default.do, that suffix is the empty string. So, nothing gets stripped.

Kind regard,
–Michael