With the previous version, the following case would fail.
It would use python 2.7.15 when running pip
instead of version 3.7.2.
Shim for `pip`
```bash
exec /home/daniel/.asdf/bin/asdf exec "pip" "$@"
```
`.tool-versions`:
```
python 3.7.2 2.7.15 system
```
Add a "shell" command similar to the existing "global" and "local"
commands, which sets the version in an environment variable instead of
writing it to a file. This was inspired by the similar functionality in
rbenv.
It works by adding a wrapper function for the asdf command. It forwards
to a "sh-shell" command that returns the exports as shell code which is
then evaled by the wrapper. This is a little gross, but we need to run
the code in the shell context in order to set variables.
Resolves#378
- Make shim-exec, shim-env, and which use the same logic to look for commands
- Make sure shim-exec and which use a plugin exec-path hook as documented
(the hook takes a relative path to the executable and returns also
a relative path, possibly modified)
- Fix shellchecks
Suppose a `foo` plugin is installed and provides a `bar` executable.
The following hooks will be executed when set in `.asdfrc`:
```shell
post_asdf_install_foo = echo installed foo version ${1}
post_asdf_reshim_foo = echo reshimmed foo version ${1}
pre_foo_bar = echo about to execute command bar from foo with args: ${@}
post_foo_bar = echo just executed command bar from foo with args: ${@}
```
Features
* New shim version meta-data allows shims to not depend on a particular plugin
nor on its relative executable path (#431)
Upgrading requires shim re-generation and should happen automatically
by `asdf-exec`:
`rm -rf ~/.asdf/shims/` followed by `asdf reshim`
* Added lots of tests for shim execution.
We now make sure that shim execution obeys plugins hooks like
`list-bin-paths` and `exec-path`.
* Shim exec is now performed by a new `bin/private/asdf-tool-exec` that might
be faster for most common use case: (versions on local .tool-versions file)
but fallbacks to slower `get_preset_version_for` which takes legacy formats
into account.
* Shim exec recommends which plugins or versions to set when command is
not found.
Fixed Bugs
* Allow many plugins to provide shims with same executable name (#431)
Previous implementation exits abruptly when no version is installed for
a plugin. This prevented the list command from listing the versions for
some other plugins.
This commit allows list command to continue executing even when no
version is installed for some plugins.
Example, plugin a with 1.0, b with none, and c with 2.0.
Previous implementation:
```
$ asdf list
a
1.0
b
No versions installed
```
After commit changes:
```
$ asdf list
a
1.0
b
No versions installed
c
2.0
```
