uppercase in .nvmrc are handled differently for `use` and `install` commands

[thomasfromont-adeo]

Operating system and version:

Linux (archlinux)

nvm debug output:

nvm --version: v0.40.1
$SHELL: /bin/zsh
$SHLVL: 2
whoami: 'tfromont'
${HOME}: /home/tfromont
${NVM_DIR}: '${HOME}/.nvm'
${PATH}: ${NVM_DIR}/versions/node/v18.20.4/bin:${HOME}/.cargo/bin:${HOME}/.local/bin:/opt/google-cloud-cli/bin:/usr/local/sbin:/usr/local/bin:/usr/bin:/var/lib/flatpak/exports/bin:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/usr/lib/rustup/bin
$PREFIX: ''
${NPM_CONFIG_PREFIX}: ''
$NVM_NODEJS_ORG_MIRROR: ''
$NVM_IOJS_ORG_MIRROR: ''
shell version: 'zsh 5.9 (x86_64-pc-linux-gnu)'
uname -a: 'Linux 6.10.6-arch1-1 #1 SMP PREEMPT_DYNAMIC Mon, 19 Aug 2024 17:02:39 +0000 x86_64 GNU/Linux'
checksum binary: 'sha256sum'
OS version: Arch Linux  ()
awk: /usr/bin/awk, GNU Awk 5.3.0, API 4.0, PMA Avon 8-g1, (GNU MPFR 4.2.1, GNU MP 6.3.0)
curl: /usr/bin/curl, curl 8.9.1 (x86_64-pc-linux-gnu) libcurl/8.9.1 OpenSSL/3.3.1 zlib/1.3.1 brotli/1.1.0 zstd/1.5.6 libidn2/2.3.7 libpsl/0.21.5 libssh2/1.11.0 nghttp2/1.63.0 nghttp3/1.5.0
wget: /usr/bin/wget, GNU Wget 1.24.5 compilé sur linux-gnu.
git: /usr/bin/git, git version 2.46.0
ls: impossible d'accéder à 'grep:': Aucun fichier ou dossier de ce nom
grep: grep: aliased to grep --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn,.idea,.tox} (grep --color=auto --exclude-dir={.bzr,CVS,.git,.hg,.svn,.idea,.tox}), grep (GNU grep) 3.11
sed: /usr/bin/sed, sed (GNU sed) 4.9
cut: /usr/bin/cut, cut (GNU coreutils) 9.5
basename: /usr/bin/basename, basename (GNU coreutils) 9.5
rm: /usr/bin/rm, rm (GNU coreutils) 9.5
mkdir: /usr/bin/mkdir, mkdir (GNU coreutils) 9.5
xargs: /usr/bin/xargs, xargs (GNU findutils) 4.10.0
nvm current: v18.20.4
which node: ${NVM_DIR}/versions/node/v18.20.4/bin/node
which iojs: iojs not found
which npm: ${NVM_DIR}/versions/node/v18.20.4/bin/npm
npm config get prefix: ${NVM_DIR}/versions/node/v18.20.4
npm root -g: ${NVM_DIR}/versions/node/v18.20.4/lib/node_modules

nvm ls output:

       v14.21.3
->     v18.20.4
       v20.17.0
        v22.6.0
         system
default -> lts/hydrogen (-> v18.20.4)
iojs -> N/A (default)
unstable -> N/A (default)
node -> stable (-> v22.6.0) (default)
stable -> 22.6 (-> v22.6.0) (default)
lts/* -> lts/iron (-> v20.17.0)
lts/argon -> v4.9.1 (-> N/A)
lts/boron -> v6.17.1 (-> N/A)
lts/carbon -> v8.17.0 (-> N/A)
lts/dubnium -> v10.24.1 (-> N/A)
lts/erbium -> v12.22.12 (-> N/A)
lts/fermium -> v14.21.3
lts/gallium -> v16.20.2 (-> N/A)
lts/hydrogen -> v18.20.4
lts/iron -> v20.17.0

How did you install nvm?

Archlinux AUR (community package registry) using an AUR helper (yay in my case`

What steps did you perform?

• default node version is set to node v18
• a project have a .nvmrc file which contains the following lts/Iron
• Go to that project and run nvm use

What happened?

• nvm use commands output an error telling "lts/Iron" is not yet installed

but a corresponding v20 node is already installed, but still running nvm install to be sure

• nvm install finds the corresponding installed version, and use it

What did you expect to happen?

Expected the nvm use to find the already installed version, like nvm install did, and use it.

To be fair, the workaround is simply to fix the uppercase in the .nvmrc file (from lts/Iron to lts/iron), I just wanted to create the issue if other stumble accross the same behavior.

[ljharb]

It indeed should only be lowercase. how did the uppercase version end up in .nvmrc?

[thomasfromont-adeo]

I guess nobody cared and eventually it got merged like this 😄

[ljharb]

so, i'm not sure what nvm should be doing here - lts/Iron was indeed not installed, because lts/iron is the alias nvm knows about.

[thomasfromont-adeo]

I see two possibilities:

• either the content of the .nvmrc file has to be well formed, and we can close this issue.
• or there can be a change in the handling of the content of the file, using the lowercase() function on the input, to match the listed lts aliases

[ljharb]

The first bullet point is the case, but that does also mean nvm validates it (npx nvmrc should cover well-formedness, though, which is not the case here - this is just about a missing alias)

Certainly nvm could be case-insensitive with its LTS aliases, but that’s a lot of complexity and implicitness for an exceedingly uncommon case (and now nvm has --save, so hand-written nvmrc files aren’t needed as much)

[ljharb]

rereading the OP, the bug seems to be that nvm install worked, not that nvm use didn't. I'll see what I can do.