[Gradle, WASM] Move stability warning to Diagnostics Infra

And report it only once per build, so it doesn't spam users with
multiple projects in the logs.

^KT-66429 Verification Pending

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

@@ -867,6 +867,12 @@ object KotlinToolingDiagnostics {
             )
         }
     }
+
+    object WasmStabilityWarning : ToolingDiagnosticFactory(WARNING) {
+        operator fun invoke(): ToolingDiagnostic =
+            build("New 'wasm' target is Work-in-Progress and is subject to change without notice. " +
+                        "Please report encountered issues to https://kotl.in/issue")
+    }
 }
 
 private fun String.indentLines(nSpaces: Int = 4, skipFirstLine: Boolean = true): String {

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/ir/KotlinWasmTargetPreset.kt

@@ -8,6 +8,8 @@ package org.jetbrains.kotlin.gradle.targets.js.ir
 import org.gradle.api.Project
 import org.jetbrains.kotlin.gradle.DeprecatedTargetPresetApi
 import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnostics
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.reportDiagnosticOncePerBuild
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinCompilationFactory
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinOnlyTargetPreset
 import org.jetbrains.kotlin.gradle.targets.js.KotlinWasmTargetType
@@ -23,7 +25,7 @@ class KotlinWasmTargetPreset(
 
     override fun instantiateTarget(name: String): KotlinJsIrTarget {
         if (!PropertiesProvider(project).wasmStabilityNoWarn) {
-            project.logger.warn("New 'wasm' target is Work-in-Progress and is subject to change without notice.")
+            project.reportDiagnosticOncePerBuild(KotlinToolingDiagnostics.WasmStabilityWarning())
         }
 
         val irTarget = project.objects.newInstance(KotlinJsIrTarget::class.java, project, KotlinPlatformType.wasm)

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/unitTests/diagnosticsTests/MppDiagnosticsFunctionalTest.kt

@@ -6,10 +6,11 @@
 package org.jetbrains.kotlin.gradle.unitTests.diagnosticsTests
 
 import org.jetbrains.kotlin.gradle.dsl.targetFromPresetInternal
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnostics
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmWithJavaTargetPreset
-import org.jetbrains.kotlin.gradle.util.androidLibrary
+import org.jetbrains.kotlin.gradle.targets.js.dsl.ExperimentalWasmDsl
+import org.jetbrains.kotlin.gradle.util.*
 import org.jetbrains.kotlin.gradle.util.checkDiagnosticsWithMppProject
-import org.jetbrains.kotlin.gradle.util.kotlin
 import org.junit.Test
 
 class MppDiagnosticsFunctionalTest {
@@ -126,4 +127,39 @@ class MppDiagnosticsFunctionalTest {
             }
         }
     }
+
+    @Test
+    @OptIn(ExperimentalWasmDsl::class)
+    fun wasmStabilityWarningReportedOncePerBuild() {
+        val rootProject = buildProjectWithMPP(projectBuilder = { withName("lib") }) {
+            kotlin { jvm(); wasmJs { browser() } }
+        }
+        val childProject = buildProjectWithMPP(projectBuilder = { withParent(rootProject).withName("app") }) {
+            kotlin { jvm(); wasmJs { browser() } }
+        }
+        childProject.evaluate()
+        rootProject.evaluate()
+
+        // wasm target was declared first in the root project, so only root project should report it
+        rootProject.assertContainsDiagnostic(KotlinToolingDiagnostics.WasmStabilityWarning)
+        childProject.assertNoDiagnostics(KotlinToolingDiagnostics.WasmStabilityWarning)
+    }
+
+    @Test
+    @OptIn(ExperimentalWasmDsl::class)
+    fun wasmStabilityWarningCanBeSuppressed() {
+        val rootProject = buildProjectWithMPP(projectBuilder = { withName("lib") }) {
+            enableWasmStabilityNoWarn()
+            kotlin { jvm(); wasmJs { browser() } }
+        }
+        val childProject = buildProjectWithMPP(projectBuilder = { withParent(rootProject).withName("app") }) {
+            enableWasmStabilityNoWarn()
+            kotlin { jvm(); wasmJs { browser() } }
+        }
+        childProject.evaluate()
+        rootProject.evaluate()
+
+        rootProject.assertNoDiagnostics(KotlinToolingDiagnostics.WasmStabilityWarning)
+        childProject.assertNoDiagnostics(KotlinToolingDiagnostics.WasmStabilityWarning)
+    }
 }

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/util/buildProject.kt

@@ -139,3 +139,6 @@ fun Project.enableDependencyVerification(enabled: Boolean = true) {
     else DependencyVerificationMode.OFF
 }
 
+fun Project.enableWasmStabilityNoWarn(enabled: Boolean = true) {
+    propertiesExtension.set("kotlin.wasm.stability.nowarn", enabled.toString())
+}