kotlinkotlin-dokkakdoc

Dokka: include code samples into package documentation


How do I include (tested, non-stale) code samples into Dokka package documentation?


More specifically, assuming that I have this configuration in my build.gradle.kts:

withType<DokkaTask> {
    outputFormat = "html"
    outputDirectory = "$buildDir/documentation"
    includes = listOf("packageDocumentation.md")
    samples = listOf("$rootDir/src/test/kotlin/some/project/TheSamples.kt")
}

And then some test code:

package some.project
import org.junit.jupiter.api.Test

class TheSamples {
    @Test
    fun helloWorldSample() {
        println("hello, world")
    }
}

and also a package documentation Markdown file:

# Package some.project

This is the documentation for some package.

@sample some.project.TheSamples#helloWorldSample

, how do I include the println(...)-part into the documentation? Is it supported at all in the current version of Dokka?


Exchanging # for . or replacing @sample by @includeFunction didn't do anything.

Furthermore:


Solution

  • The @sample tag is placed in the comment of the function or class you want to document with a sample of how to call it, or use it.

    @sample takes a fully qualified class and function name as an argument. When generating API docs with Dokka that reference is replaced with the content of the referenced function. Typically you'd have a function that you'd like to document with a sample of the test function, but here, your test function isn't calling anything to test, so this example may appear trivial, but this is the form:

    /**
     * This is a function that I want to document with a sample.
     *
     * @sample some.project.TheSamples.helloWorldSample
     */
    fun getHelloWorld() {
      // Do stuff
    }
    

    When dokka processes the files, the sample code is appended onto the information in the comment. Below is a rough approximation of dokka's HTML output.

    getHelloWorld

    fun getHelloWorld()

    This is a function that I want to document with a sample.

    println("hello, world")


    I found the following references helpful:

    https://livebook.manning.com/book/kotlin-in-action/appendix-b/7

    https://medium.com/@rfletcher_96265/testable-samples-in-kotlin-api-docs-f7cd2da17c4f