Publish releases from macOS so iOS targets resolve

.github/workflows/publish-on-maven.yml

@@ -30,11 +30,29 @@ jobs:
 
   publish:
     needs: build-natives
-    runs-on: ubuntu-latest
+    # MUST stay on macOS: iosArm64 / iosSimulatorArm64 are disabled on any other
+    # host, and Kotlin then writes the root module metadata with Gradle-default
+    # coordinates for them (`composewebview:webview-compose-iosarm64:unspecified`),
+    # which makes the release unresolvable for iOS consumers (issue #51).
+    # :webview-compose:verifyPublicationCoordinates guards against a regression.
+    runs-on: macos-15
     steps:
       - name: Checkout code
         uses: actions/checkout@v4
 
+      - name: Select Xcode 26+ (Compose 1.11 needs iOS 26 SDK)
+        run: |
+          # Same selection as the iOS jobs in pr-build-check.yml.
+          XCODE=$(ls -d /Applications/Xcode_26*.app 2>/dev/null | sort -V | tail -1 || true)
+          if [ -z "$XCODE" ]; then
+            XCODE=$(ls -d /Applications/Xcode_16*.app 2>/dev/null | sort -V | tail -1 || true)
+          fi
+          if [ -n "$XCODE" ]; then
+            echo "Using $XCODE"
+            sudo xcode-select -s "$XCODE"
+          fi
+          xcodebuild -version
+
       - name: Download native artifacts
         uses: actions/download-artifact@v4
         with:

webview-compose/build.gradle.kts

@@ -1,6 +1,7 @@
 @file:OptIn(ExperimentalWasmDsl::class)
 
 import com.vanniktech.maven.publish.KotlinMultiplatform
+import groovy.json.JsonSlurper
 import org.apache.tools.ant.taskdefs.condition.Os
 import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
 
@@ -208,3 +209,55 @@ mavenPublishing {
         description.set("Compose Multiplatform WebView library for Desktop, Android and iOS")
     }
 }
+
+// The root KMP module metadata redirects every target variant to a sibling module
+// through an `available-at` entry. Targets that are disabled on the publishing host
+// (Apple targets anywhere but macOS) keep Gradle's default project coordinates, so
+// the release ships pointing at `composewebview:webview-compose-iosarm64:unspecified`
+// and no iOS consumer can resolve it (issue #51). Fail the publish instead.
+val verifyPublicationCoordinates by tasks.registering {
+    description = "Checks that the KMP root module metadata only points at modules being published"
+    group = "verification"
+
+    val metadataFile = tasks.named<GenerateModuleMetadata>(
+        "generateMetadataFileForKotlinMultiplatformPublication"
+    ).flatMap { it.outputFile }
+
+    inputs.file(metadataFile)
+
+    doLast {
+        @Suppress("UNCHECKED_CAST")
+        val root = JsonSlurper().parse(metadataFile.get().asFile) as Map<String, Any>
+
+        @Suppress("UNCHECKED_CAST")
+        val component = root["component"] as Map<String, Any>
+        val group = component["group"]
+        val version = component["version"]
+
+        @Suppress("UNCHECKED_CAST")
+        val variants = root["variants"] as? List<Map<String, Any>> ?: emptyList()
+        val dangling = variants.mapNotNull { variant ->
+            @Suppress("UNCHECKED_CAST")
+            val at = variant["available-at"] as? Map<String, Any> ?: return@mapNotNull null
+            if (at["group"] == group && at["version"] == version) return@mapNotNull null
+            "${variant["name"]} -> ${at["group"]}:${at["module"]}:${at["version"]}"
+        }
+
+        check(dangling.isEmpty()) {
+            buildString {
+                appendLine("Root module metadata points at modules outside this publication:")
+                dangling.forEach { appendLine("  $it") }
+                appendLine("Expected $group:*:$version.")
+                append(
+                    "Publish from a host that can build every declared target " +
+                        "(macOS is required for the iOS targets)."
+                )
+            }
+        }
+        logger.lifecycle("Publication coordinates OK: ${variants.size} variants under $group:*:$version")
+    }
+}
+
+tasks.withType<AbstractPublishToMaven>().configureEach {
+    dependsOn(verifyPublicationCoordinates)
+}