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Node CLI eval option can't take unary negation operator #43397
Description
Version
v17.9.0
Platform
Darwin [redacted] 19.6.0 Darwin Kernel Version 19.6.0: Tue Feb 15 21:39:11 PST 2022; root:xnu-6153.141.59~1/RELEASE_X86_64 x86_64
Subsystem
No response
What steps will reproduce the bug?
Execute the following:
$ node -pe "-0"And you will get back:
node: --eval requires an argument
In fact, anything where the - comes first, you get this message.
For example, all of the following also result in the above message:
$ node -pe "-42"
$ node -pe "-"
$ node -pe "-NaN"How often does it reproduce? Is there a required condition?
It's always reproducable (at least on this version and machine).
What is the expected behavior?
I'd like it to not spit back an error message and give me the evaluated value, please.
What do you see instead?
An error message detailing that the "eval" option was not given a value.
Additional information
It seems that the CLI is not properly parsing its arguments?
Prefixing the expression with 0 seems to work:
$ node -pe "0-42"
42As well as using a comma operator:
$ node -pe "(0, -42)"
-42
Activity
bnoordhuis commentedon Jun 13, 2022
It's rather doing it too well! It parses
-42as a flag, not as a positional argument.I agree it's a bug but I pity whoever goes in to grapple with node's option parser. You're a braver person than I am.
LiviaMedeiros commentedon Jun 13, 2022
Before any brave soul goes on fixing this: we probably don't want
node -pe "-something"to be interpreted as anything butnode -pesomthingornode -p -e -s -o -m -e -t -h -i -n -g.I think, the proper command should look more like
node -pe -- -42, where--argument will mean that all further arguments are NOT options.bnoordhuis commentedon Jun 14, 2022
Can you explain your line of thought? Why should it be
node -pesomthingornode -p -e -s -o -m -e -t -h -i -n -g?LiviaMedeiros commentedon Jun 14, 2022
My line of thought is based on:
-ab==-a -b)-afoo==-a foo)Otherwise, short options should allow arbitrary order (
-b -a==-a -b)-a -foo -b==-a -f -o -o -b). If we need a positional argument starting (or potentially starting) with dash, we can use double dash separator (-a -b -- -foo).Thus said, this is how I'd like to expect parsing to work:
node -e42should work the same asnode -e 42, not "bad option"Otherwise,
node -ep 42might work the same asnode -pe 42as long as it's unambiguousnode -e --throw-deprecation [...]should never attempt to evaluate--throw-deprecationas js codenode --helpdoes mention--which should indicate that following arguments are positional. However, neithernode -e -- 42ornode -- "-dashfile.js"are available.For users who prefer setting mandatory option arguments rather than positional arguments,
node --print --eval=-42already works. :)doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts
doc,test: clarify --eval syntax for leading '-' scripts