创建别名（或类似名称），该别名在cd进入特定文件夹后会激活

Question

Is it possible to create aliases when I enter a certain folder?

What I want:

I use composer a lot (a PHP package manager), which installs binaries in ./vendor/bin . I would like to run the binaries directly from . .

For example:

/path/to/project
 | - composer.json     // dictates dependencies for the project
 | - vendor            // libs folder for composer, is created by composer
 |    | - bin          // if lib has bin, composer creates this folder
 |    |    | phpunit   // binary
 |    |    | phinx     // binary
 |    | - somelib1     // downloaded by composer
 |    | - somelib2     // downloaded by composer

Is it possible to get this to work:

> cd /path/to/project
> phpunit

And get phpunit to execute?

Something like "sensing" the composer.json file and dynamically find the binaries in ./vendor/bin and then do something like alias="./vendor/bin/<binary-name> $@" automatically?

I use OS X 10.9 and the boxed in Terminal app.

Answer 1

You can override cd , trap my_function DEBUG to run something on every command, or add a command into PS1 or PROMPT_COMMAND .

These have different behaviour and caveats, and I can't recommend doing any of them for this use case (after having used each of them at some point). They are bad solutions to XY problems .

An alternative which is much less likely to break things horribly is to create a custom function to do both things:

cdp() {
    cd "$@" && phpunit
}