Repository: nvm
Issue:  sourcing nvm.sh exits with code 3 when .nvmrc is present and version is not installed
Labels: needs followup

When I source `nvm.sh` like `. "$HOME/.nvm/nvm.sh"` for manual install and like `. $(brew --prefix nvm)/nvm.sh`, the exit code is `3`.

Even though nvm works after that, in bash scripts with `set -e`, the script stops there, since the command exits with a non-zero value.

Is there a reason this fails?
Is there a reason it exits with `3`, if it's not an actual failure?
What can we do about that?

Some extra info:
- output of `. nvm.sh` with `set -x` for "tracing":
https://pastebin.com/raw/1Tk9UUsp

- Operating system and version: macOS 10.14.2 (mojave)

- `nvm debug` output:
<details>
<summary>Details</summary>

```sh
﻿nvm --version: v0.34.0
$TERM_PROGRAM: iTerm.app
$SHELL: /bin/zsh
$SHLVL: 1
$HOME: /Users/pvinis
$NVM_DIR: '$HOME/.nvm'
$PATH: $HOME/.gem/ruby/2.5.1/bin:$HOME/.rubies/ruby-2.5.1/lib/ruby/gems/2.5.0/bin:$HOME/.rubies/ruby-2.5.1/bin:$NVM_DIR/versions/node/v11.0.0/bin:$HOME/.config/yarn/global/node_modules/.bin:$HOME/.yarn/bin:$HOME/Library/Python/3.7/bin:$HOME/.fastlane/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/MacGPG2/bin:/opt/X11/bin:$HOME/.rvm/bin
$PREFIX: ''
$NPM_CONFIG_PREFIX: ''
$NVM_NODEJS_ORG_MIRROR: ''
$NVM_IOJS_ORG_MIRROR: ''
shell version: 'zsh 5.3 (x86_64-apple-darwin18.0)'
uname -a: 'Darwin 18.2.0 Darwin Kernel Version 18.2.0: Mon Nov 12 20:24:46 PST 2018; root:xnu-4903.231.4~2/RELEASE_X86_64 x86_64'
OS version: Mac 10.14.2 18C54
curl: /usr/bin/curl, curl 7.54.0 (x86_64-apple-darwin18.0) libcurl/7.54.0 LibreSSL/2.6.4 zlib/1.2.11 nghttp2/1.24.1
wget: not found
git: /usr/local/bin/git, git version 2.19.1
grep: /usr/bin/grep, grep (BSD grep) 2.5.1-FreeBSD
awk: /usr/bin/awk, awk version 20070501
sed: illegal option -- -
usage: sed script [-Ealn] [-i extension] [file ...]
       sed [-Ealn] [-i extension] [-e script] ... [-f script_file] ... [file ...]
sed: /usr/bin/sed,
cut: illegal option -- -
usage: cut -b list [-n] [file ...]
       cut -c list [file ...]
       cut -f list [-s] [-d delim] [file ...]
cut: /usr/bin/cut,
basename: illegal option -- -
usage: basename string [suffix]
       basename [-a] [-s suffix] string [...]
basename: /usr/bin/basename,
rm: illegal option -- -
usage: rm [-f | -i] [-dPRrvW] file ...
       unlink file
rm: /bin/rm,
mkdir: illegal option -- -
usage: mkdir [-pv] [-m mode] directory ...
mkdir: /bin/mkdir,
xargs: illegal option -- -
usage: xargs [-0opt] [-E eofstr] [-I replstr [-R replacements]] [-J replstr]
             [-L number] [-n number [-x]] [-P maxprocs] [-s size]
             [utility [argument ...]]
xargs: /usr/bin/xargs,
nvm current: v11.0.0
which node: $NVM_DIR/versions/node/v11.0.0/bin/node
which iojs: iojs not found
which npm: $NVM_DIR/versions/node/v11.0.0/bin/npm
npm config get prefix: $NVM_DIR/versions/node/v11.0.0
npm root -g: $NVM_DIR/versions/node/v11.0.0/lib/node_modules
```
</details>

- `nvm ls` output:
<details>
    <summary>Details</summary>

```sh
        v8.12.0
       v10.12.0
->      v11.0.0
         system
default -> v11 (-> v11.0.0)
node -> stable (-> v11.0.0) (default)
stable -> 11.0 (-> v11.0.0) (default)
iojs -> N/A (default)
unstable -> N/A (default)
lts/* -> lts/dubnium (-> N/A)
lts/argon -> v4.9.1 (-> N/A)
lts/boron -> v6.14.4 (-> N/A)
lts/carbon -> v8.12.0
lts/dubnium -> v10.13.0 (-> N/A)
```
</details>

- How did you install `nvm`? (e.g. install script in readme, Homebrew):
Tried both. I mostly do from brew though, since it's easier.

- What steps did you perform?
source the file

- What happened?
worked, but exits with non-zero value

- What did you expect to happen?
to exit with a 0 value since everything seemingly went well

- Is there anything in any of your profile files (`.bashrc`, `.bash_profile`, `.zshrc`, etc) that modifies the `PATH`?
I ran this without any $PATH alterations. In general I don't have anything in there that touch nvm. Only to include `brew` stuff.