Where's dist() method located - gradle

Question

I'm trying to understand gradle distribution. In the gradle documentation, section 7.3.4, there's the following code example:
task dist(type: Zip) {
dependsOn spiJar
from 'src/dist'
into('libs') {
from spiJar.archivePath
from configurations.runtime
}
}
I was trying to find method dist() to understand what exact it does. I was searching for in org.gradle.api.tasks.bundling.Zip but there is no such method. So where is it declared?

Answer 1

Could You please provide a link to the example You mentioned?
It seems that dist() method is defined nowhere. The code sample You provided is just a task definition so in this particular case dist is just a name of the defined task of type Zip. from and into methods are taken from AbstractCopyTask.
EDIT
So, as stated above dist() is just an ordinary task definition, while for instance the next piece of code in the example:
artifacts {
archives dist
}
has a dedicated method defined in AbstractProject class:
public void artifacts(Closure configureClosure) {
ConfigureUtil.configure(configureClosure, getArtifacts());
}
Now, why this error:
Could not find method dist() for arguments [{type=class org.gradle.api.tasks.bundling.Zip}, txt, build_275gv6pdo8dsig251h253koq9t$_run_closure2#a81512] on proj ect ':MP'.
occurs for this input:
task dist(type: Zip, 'txt')
?
During script parsing (which is a dynamic and quite complicated process) the declaration above should be turned into invocation of one of create methods on TaskContainer instance, where dist is a task name of type String and type: Zip, 'txt' should be passed as arguments. As You can see in the docs for TaskContainer there's no create method that takes String (dist - task name), then Map (type: Zip - task config), and again a String (txt - redundant/invalid argument). That's why it's failing.
If You're interested how it works, it's good idea to put the following piece of code in build.gradle:
task someTask {
throw new RuntimeException()
}
and investigate the stacktrace. It will tell You a lot about how it works step by step.

Answer 2

There is no dist method. In this example, you are using the gradle dsl to create a new task called "dist" whose type is "Zip".
This is accomplished through the use of "method missing". See http://groovy.codehaus.org/Using+methodMissing+and+propertyMissing for more info.
Note: if you change "dist" to "foo", this is still a valid example, but with a less self-explanatory task name.