test(library): compare runner labels supported by GitHub with supported by library

Author: krzema12

github-workflows-kt/src/test/kotlin/io/github/typesafegithub/workflows/domain/GithubHostedRunnerLabelsListing.kt

@@ -7,19 +7,19 @@ import io.ktor.client.statement.bodyAsText
 /**
  * Lists values allowed to be set in "runs-on" for a job, for GitHub-hosted runners.
  */
-suspend fun listRunnerLabels(): List<String> {
+suspend fun listRunnerLabels(): Set<String> {
     val html = HttpClient().get(GITHUB_RUNNER_LABELS_DOCS_URL).bodyAsText()
     return parse(html)
 }
 
 private const val GITHUB_RUNNER_LABELS_DOCS_URL: String =
     "https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions"
 
-private fun parse(html: String): List<String> =
+private fun parse(html: String): Set<String> =
     RUNNER_LABEL_REGEX
         .findAll(html)
         .map { it.groupValues[1] }
-        .toList()
+        .toSet()
 
 private val RUNNER_LABEL_REGEX =
     Regex(

github-workflows-kt/src/test/kotlin/io/github/typesafegithub/workflows/domain/RunnerTypeTest.kt

@@ -1,10 +1,32 @@
 package io.github.typesafegithub.workflows.domain
 
+import io.kotest.assertions.assertSoftly
 import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.assertions.withClue
 import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.shouldBe
 
 class RunnerTypeTest :
     FunSpec({
+        test("all supported runner labels should correspond to lib's classes") {
+            val fromLib =
+                RunnerType.GitHubHosted::class
+                    .sealedSubclasses
+                    .mapNotNull { it.objectInstance?.value }
+                    .toSet()
+            val fromDocs = listRunnerLabels().toSet()
+
+            assertSoftly {
+                withClue("no obsolete labels are in the lib") {
+                    fromLib - fromDocs shouldBe emptySet<String>()
+                }
+
+                withClue("no missing labels are in the lib") {
+                    fromDocs - fromLib shouldBe emptySet<String>()
+                }
+            }
+        }
+
         context("Labelled") {
             test("should throw on invalid arguments") {
                 shouldThrow<IllegalArgumentException> {