[MPP] Emit a warning when kotlin-test testing framework couldn't be inferred

^KT-56828

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/internal/kotlinTestDependencyManagement.kt

@@ -28,6 +28,9 @@ import org.jetbrains.kotlin.gradle.dsl.KotlinSingleTargetExtension
 import org.jetbrains.kotlin.gradle.dsl.KotlinTopLevelExtension
 import org.jetbrains.kotlin.gradle.execution.KotlinAggregateExecutionSource
 import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.plugin.PropertiesProvider.Companion.kotlinPropertiesProvider
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnostics
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.reportDiagnostic
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmAndroidCompilation
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinWithJavaTarget
 import org.jetbrains.kotlin.gradle.plugin.sources.KotlinDependencyScope
@@ -144,6 +147,10 @@ private fun Configuration.maybeAddTestDependencyCapability(
                             }
                     }
                 )
+            } else {
+                compilation.project.reportDiagnostic(
+                    KotlinToolingDiagnostics.KotlinTestFrameworkInferenceFailed(name)
+                )
             }
         }
     }

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics.kt

@@ -520,6 +520,16 @@ object KotlinToolingDiagnostics {
         )
     }
 
+    object KotlinTestFrameworkInferenceFailed : ToolingDiagnosticFactory(WARNING) {
+        operator fun invoke(configurationName: String) = build(
+            """
+                kotlin-test was added to a non-testing configuration "$configurationName" where test framework couldn't be inferred.
+                
+                Learn how to configure kotlin-test at: https://kotl.in/kotlin-test-frameworks
+            """.trimIndent()
+        )
+    }
+
     object XCFrameworkDifferentInnerFrameworksName : ToolingDiagnosticFactory(WARNING) {
         operator fun invoke(xcFramework: String, innerFrameworks: String) = build(
             "Name of XCFramework '$xcFramework' differs from inner frameworks name '$innerFrameworks'! Framework renaming is not supported yet"

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/dependencyResolutionTests/KotlinTestDependencyWithoutTestFrameworkTest.kt

@@ -0,0 +1,116 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+@file:Suppress("FunctionName")
+
+package org.jetbrains.kotlin.gradle.dependencyResolutionTests
+
+import org.gradle.api.NamedDomainObjectProvider
+import org.gradle.api.artifacts.Configuration
+import org.gradle.api.internal.project.ProjectInternal
+import org.gradle.kotlin.dsl.dependencies
+import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
+import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformSourceSetConventionsImpl.dependencies
+import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet
+import org.jetbrains.kotlin.gradle.plugin.extraProperties
+import org.jetbrains.kotlin.gradle.util.*
+import org.jetbrains.kotlin.gradle.util.assertNoDiagnostics
+import kotlin.test.Test
+
+class KotlinTestFrameworkInferenceFailedTest {
+
+    @Test
+    fun `KMP project - when jvmTest depends on kotlin-test - emits no diagnostics`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            kmpProjectWithJvm { sourceSets.jvmTest.dependOnKotlinTest() }
+        }.assertNoDiagnostics()
+    }
+
+    @Test
+    fun `KMP project - when commonTest depends on kotlin-test - emits no diagnostics`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            kmpProjectWithJvm { sourceSets.commonTest.dependOnKotlinTest() }
+        }.assertNoDiagnostics()
+    }
+
+    @Test
+    fun `KMP project - when jvmMain depends on kotlin-test - emits a diagnostic`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            kmpProjectWithJvm { sourceSets.jvmMain.dependOnKotlinTest() }
+        }.checkDiagnostics("kotlin-test-kmp-jvmMain")
+    }
+
+    @Test
+    fun `KMP project - when commonMain depends on kotlin-test - emits a diagnostic`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            kmpProjectWithJvm { sourceSets.commonMain.dependOnKotlinTest() }
+        }.checkDiagnostics("kotlin-test-kmp-commonMain")
+    }
+
+    @Test
+    fun `KMP project without jvm - when commonMain depends on kotlin-test - emits no diagnostics`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            buildProjectWithMPP {
+                kotlin {
+                    linuxArm64()
+                    linuxX64()
+
+                    sourceSets.commonMain.dependOnKotlinTest()
+                }
+            }
+        }.assertNoDiagnostics()
+    }
+
+    @Test
+    fun `JVM project - when testImplementation depends on kotlin-test - emits no diagnostics`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            buildProjectWithJvm {
+                dependencies {
+                    "testImplementation"("org.jetbrains.kotlin:kotlin-test")
+                }
+            }
+        }.assertNoDiagnostics()
+    }
+
+    @Test
+    fun `JVM project - when implementation depends on kotlin-test - emits a diagnostic`() {
+        evaluateProjectAndResolveConfigurationsWhen {
+            buildProjectWithJvm {
+                dependencies {
+                    "implementation"("org.jetbrains.kotlin:kotlin-test")
+                }
+            }
+        }.checkDiagnostics("kotlin-test-jvm-implementation")
+    }
+
+    private fun kmpProjectWithJvm(configure: KotlinMultiplatformExtension.() -> Unit): ProjectInternal {
+        return buildProjectWithMPP {
+            kotlin {
+                jvm()
+                linuxArm64()
+
+                configure(this)
+            }
+        }
+    }
+
+    private fun NamedDomainObjectProvider<KotlinSourceSet>.dependOnKotlinTest() {
+        dependencies {
+            implementation(kotlin("test"))
+        }
+    }
+
+    private fun evaluateProjectAndResolveConfigurationsWhen(
+        projectFactory: () -> ProjectInternal
+    ): ProjectInternal {
+        val project = projectFactory()
+        project.repositories.mavenLocal()
+        project.repositories.mavenCentralCacheRedirector()
+        project.evaluate()
+        project.configurations.filter(Configuration::isCanBeResolved).forEach(Configuration::resolve)
+        return project
+    }
+
+}

libraries/tools/kotlin-gradle-plugin/src/functionalTest/resources/expectedDiagnostics/kotlin-test-jvm-implementation.txt

@@ -0,0 +1,3 @@
+[KotlinTestFrameworkInferenceFailed | WARNING] kotlin-test was added to a non-testing configuration "implementation" where test framework couldn't be inferred.
+
+Learn how to configure kotlin-test at: https://kotl.in/kotlin-test-frameworks

libraries/tools/kotlin-gradle-plugin/src/functionalTest/resources/expectedDiagnostics/kotlin-test-kmp-commonMain.txt

@@ -0,0 +1,3 @@
+[KotlinTestFrameworkInferenceFailed | WARNING] kotlin-test was added to a non-testing configuration "jvmCompilationImplementation" where test framework couldn't be inferred.
+
+Learn how to configure kotlin-test at: https://kotl.in/kotlin-test-frameworks

libraries/tools/kotlin-gradle-plugin/src/functionalTest/resources/expectedDiagnostics/kotlin-test-kmp-jvmMain.txt

@@ -0,0 +1,7 @@
+[KotlinTestFrameworkInferenceFailed | WARNING] kotlin-test was added to a non-testing configuration "jvmMainImplementation" where test framework couldn't be inferred.
+
+Learn how to configure kotlin-test at: https://kotl.in/kotlin-test-frameworks
+----
+[KotlinTestFrameworkInferenceFailed | WARNING] kotlin-test was added to a non-testing configuration "jvmCompilationImplementation" where test framework couldn't be inferred.
+
+Learn how to configure kotlin-test at: https://kotl.in/kotlin-test-frameworks