test(library): add tests for reading contexts in Kotlin-based steps (#1947)

Part of
#1946.

Author: krzema12

github-workflows-kt/src/main/kotlin/io/github/typesafegithub/workflows/yaml/ContextMapping.kt

@@ -0,0 +1,17 @@
+package io.github.typesafegithub.workflows.yaml
+
+import io.github.typesafegithub.workflows.domain.contexts.Contexts
+import io.github.typesafegithub.workflows.domain.contexts.GithubContext
+import kotlinx.serialization.json.Json
+
+internal fun loadContextsFromEnvVars(getenv: (String) -> String?): Contexts {
+    fun getEnvVarOrFail(varName: String): String = getenv(varName) ?: error("$varName should be set!")
+
+    val githubContextRaw = getEnvVarOrFail("GHWKT_GITHUB_CONTEXT_JSON")
+    val githubContext = json.decodeFromString<GithubContext>(githubContextRaw)
+    return Contexts(
+        github = githubContext,
+    )
+}
+
+private val json = Json { ignoreUnknownKeys = true }

github-workflows-kt/src/main/kotlin/io/github/typesafegithub/workflows/yaml/ToYaml.kt

@@ -5,15 +5,12 @@ import io.github.typesafegithub.workflows.domain.KotlinLogicStep
 import io.github.typesafegithub.workflows.domain.Mode
 import io.github.typesafegithub.workflows.domain.Permission
 import io.github.typesafegithub.workflows.domain.Workflow
-import io.github.typesafegithub.workflows.domain.contexts.Contexts
-import io.github.typesafegithub.workflows.domain.contexts.GithubContext
 import io.github.typesafegithub.workflows.dsl.toBuilder
 import io.github.typesafegithub.workflows.internal.relativeToAbsolute
 import io.github.typesafegithub.workflows.shared.internal.findGitRoot
 import io.github.typesafegithub.workflows.yaml.Preamble.Just
 import io.github.typesafegithub.workflows.yaml.Preamble.WithOriginalAfter
 import io.github.typesafegithub.workflows.yaml.Preamble.WithOriginalBefore
-import kotlinx.serialization.json.Json
 import java.nio.file.Path
 import kotlin.io.path.absolute
 import kotlin.io.path.invariantSeparatorsPathString
@@ -72,16 +69,6 @@ internal fun Workflow.writeToFile(
     }
 }
 
-private fun loadContextsFromEnvVars(getenv: (String) -> String?): Contexts {
-    fun getEnvVarOrFail(varName: String): String = getenv(varName) ?: error("$varName should be set!")
-
-    val githubContextRaw = getEnvVarOrFail("GHWKT_GITHUB_CONTEXT_JSON")
-    val githubContext = json.decodeFromString<GithubContext>(githubContextRaw)
-    return Contexts(
-        github = githubContext,
-    )
-}
-
 private fun commentify(preamble: String): String {
     if (preamble.isEmpty()) return ""
 
@@ -174,5 +161,3 @@ private fun Workflow.toYamlInternal(jobsWithConsistencyCheck: List<Job<*>>): Map
         *_customArguments.toList().toTypedArray(),
         "jobs" to jobsWithConsistencyCheck.jobsToYaml(),
     )
-
-private val json = Json { ignoreUnknownKeys = true }

github-workflows-kt/src/test/kotlin/io/github/typesafegithub/workflows/yaml/ContextMappingTest.kt

@@ -0,0 +1,39 @@
+package io.github.typesafegithub.workflows.yaml
+
+import io.github.typesafegithub.workflows.domain.contexts.Contexts
+import io.github.typesafegithub.workflows.domain.contexts.GithubContext
+import io.github.typesafegithub.workflows.domain.contexts.GithubContextEvent
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.shouldBe
+
+class ContextMappingTest :
+    FunSpec({
+        test("successfully load all supported contexts with all supported fields") {
+            // Given
+            val testGithubContextJson = javaClass.getResource("/contexts/github.json")!!.readText()
+
+            // When
+            val contexts =
+                loadContextsFromEnvVars(
+                    getenv = mapOf(
+                        "GHWKT_GITHUB_CONTEXT_JSON" to testGithubContextJson,
+                    )::get,
+                )
+
+            // Then
+            contexts shouldBe
+                Contexts(
+                    github =
+                        GithubContext(
+                            repository = "some-owner/some-repo",
+                            sha = "db76dd0f1149901e1cdf60ec98d568b32fa7eb71",
+                            ref = "refs/heads/main",
+                            event =
+                                GithubContextEvent(
+                                    after = "1383af4847629428f1675f5c2e81e67cc3a4efb0",
+                                ),
+                            event_name = "push",
+                        ),
+                )
+        }
+    })

github-workflows-kt/src/test/resources/contexts/github.json

@@ -0,0 +1,9 @@
+{
+  "repository": "some-owner/some-repo",
+  "sha": "db76dd0f1149901e1cdf60ec98d568b32fa7eb71",
+  "ref": "refs/heads/main",
+  "event": {
+    "after": "1383af4847629428f1675f5c2e81e67cc3a4efb0"
+  },
+  "event_name": "push"
+}