[Gradle][MPP] CompositeMetadataJar: Support omitted directory entries

^KT-46198

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/CompositeMetadataJar.kt

@@ -71,20 +71,17 @@ private class CompositeMetadataJarImpl(
         val artifactFile = getArtifactFile(sourceSetName)
         val moduleOutputDirectory = outputDirectory.resolve(moduleIdentifier).also(File::mkdirs)
 
-        ZipFile(getArtifactFile(sourceSetName)).use { compoundMetadataArtifactZipFile ->
-            val cinteropRootDirectory = compoundMetadataArtifactZipFile.entries().asSequence()
-                .firstOrNull { zipEntry -> zipEntry.name == "$sourceSetName-cinterop/" && zipEntry.isDirectory }
-                ?: return emptySet()
-
-            val cinterops = compoundMetadataArtifactZipFile.listChildren(cinteropRootDirectory)
-
-            val cinteropsByOutputFile = cinterops.associateBy { cinteropZipEntry ->
-                moduleOutputDirectory.resolve("${cinteropZipEntry.name.removePrefix(cinteropRootDirectory.name).removeSuffix("/")}.klib")
-            }
+        ZipFile(getArtifactFile(sourceSetName)).use { artifactZipFile ->
+            val cinteropRootPath = "$sourceSetName-cinterop/"
+            val cinteropEntries = artifactZipFile.listChildren(cinteropRootPath)
+            val cinteropNames = cinteropEntries.map { entry ->
+                entry.name.removePrefix(cinteropRootPath).split("/", limit = 2).first()
+            }.toSet()
 
+            val cinteropsByOutputFile = cinteropNames.associateBy { cinteropName -> moduleOutputDirectory.resolve("$cinteropName.klib") }
             if (materializeFiles) {
-                cinteropsByOutputFile.forEach { (cinteropOutputFile, cinteropZipEntry) ->
-                    copyZipFilePartially(artifactFile, cinteropOutputFile, cinteropZipEntry.name)
+                cinteropsByOutputFile.forEach { (cinteropOutputFile, cinteropName) ->
+                    copyZipFilePartially(artifactFile, cinteropOutputFile, "$cinteropRootPath$cinteropName/")
                 }
             }
 

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/utils/zipUtils.kt

@@ -11,7 +11,7 @@ import java.util.zip.ZipFile
 import java.util.zip.ZipOutputStream
 
 internal fun copyZipFilePartially(sourceZipFile: File, destinationZipFile: File, path: String) {
-    require(path.endsWith("/")) { "Expected path to end with '/', found '$path'" }
+    requireValidZipPath(path)
 
     ZipFile(sourceZipFile).use { zip ->
         val entries = zip.entries().asSequence()
@@ -35,11 +35,23 @@ internal fun copyZipFilePartially(sourceZipFile: File, destinationZipFile: File,
     }
 }
 
+internal fun ZipFile.listDescendants(path: String): Sequence<ZipEntry> {
+    requireValidZipPath(path)
+    return entries().asSequence().filter { entry ->
+        entry.name != path && entry.name.startsWith(path)
+    }
+}
+
+internal fun ZipFile.listChildren(path: String): Sequence<ZipEntry> {
+    requireValidZipPath(path)
+    return listDescendants(path).filter { entry ->
+        entry.name.removePrefix(path).count { it == '/' } == 1
+    }
+}
+
 internal fun ZipFile.listDescendants(zipEntry: ZipEntry): Sequence<ZipEntry> {
     require(zipEntry.isDirectory)
-    return entries().asSequence().filter { entry ->
-        entry.name != zipEntry.name && entry.name.startsWith(zipEntry.name)
-    }
+    return listDescendants(zipEntry.name)
 }
 
 internal fun ZipFile.listChildren(zipEntry: ZipEntry): Sequence<ZipEntry> {
@@ -47,3 +59,5 @@ internal fun ZipFile.listChildren(zipEntry: ZipEntry): Sequence<ZipEntry> {
         entry.name.removePrefix(zipEntry.name).count { it == '/' } == 1
     }
 }
+
+private fun requireValidZipPath(path: String) = require(path.endsWith("/")) { "Expected path to end with '/', found '$path'" }