View Source Mix.Shell.Process (Mix v1.12.0-rc.1)
Mix shell that uses the current process mailbox for communication.
This module provides a Mix shell implementation that uses the current process mailbox for communication instead of IO.
As an example, when Mix.shell().info("hello")
is called,
the following message will be sent to the calling process:
{:mix_shell, :info, ["hello"]}
This is mainly useful in tests, allowing us to assert
if given messages were received or not instead of performing
checks on some captured IO. Since we need to guarantee a clean
slate between tests, there is also a flush/1
function
responsible for flushing all :mix_shell
related messages
from the process inbox.
Examples
Mix.shell().info("hello")
receive do
{:mix_shell, :info, [msg]} -> msg
end
#=> "hello"
send(self(), {:mix_shell_input, :prompt, "Pretty cool"})
Mix.shell().prompt?("How cool was that?!")
#=> "Pretty cool"
Link to this section Summary
Functions
Executes the given command and forwards its messages to the current process.
Forwards the error to the current process.
Flushes all :mix_shell
and :mix_shell_input
messages from the current process.
Forwards the message to the current process.
Prints the current application if it was not printed yet.
Forwards the message to the current process.
Forwards the message to the current process.
Link to this section Functions
Executes the given command and forwards its messages to the current process.
Forwards the error to the current process.
Flushes all :mix_shell
and :mix_shell_input
messages from the current process.
If a callback is given, it is invoked for each received message.
Examples
flush(&IO.inspect/1)
Forwards the message to the current process.
Prints the current application if it was not printed yet.
Forwards the message to the current process.
It also checks the inbox for an input message matching:
{:mix_shell_input, :prompt, value}
If one does not exist, it will abort since there was no shell
process inputs given. value
must be a string.
Examples
The following will answer with "Meg"
to the prompt
"What's your name?"
:
# The response is sent before calling prompt/1 so that prompt/1 can read it
send(self(), {:mix_shell_input, :prompt, "Meg"})
Mix.shell().prompt("What's your name?")
Forwards the message to the current process.
It also checks the inbox for an input message matching:
{:mix_shell_input, :yes?, value}
If one does not exist, it will abort since there was no shell
process inputs given. value
must be true
or false
.
Example
# Send the response to self() first so that yes?/1 will be able to read it
send(self(), {:mix_shell_input, :yes?, true})
Mix.shell().yes?("Are you sure you want to continue?")