refactor(composer): Turn toPackageReferences() into an expression

Signed-off-by: Frank Viernau <[email protected]>

plugins/package-managers/composer/src/main/kotlin/Composer.kt

@@ -153,12 +153,10 @@ class Composer(
         packageInfoForName: Map<String, PackageInfo>,
         virtualPackages: Set<String>,
         dependencyBranch: List<String> = emptyList()
-    ): Set<PackageReference> {
-        val packageReferences = mutableSetOf<PackageReference>()
-
+    ): Set<PackageReference> =
         getScopeDependencies(scopeName).filterNot { packageName ->
             packageName.isPlatformDependency() || packageName in virtualPackages // Virtual packages have no metadata.
-        }.forEach { packageName ->
+        }.mapNotNullTo(mutableSetOf()) { packageName ->
             val childInfo = packageInfoForName[packageName]
                 ?: throw IOException("Could not find package info for $packageName")
 
@@ -168,10 +166,10 @@ class Composer(
                         "dependency tree: ${dependencyBranch.joinToString(" -> ")}."
                 }
 
-                return@forEach
+                return@mapNotNullTo null
             }
 
-            packageReferences += PackageReference(
+            PackageReference(
                 id = childInfo.toId(),
                 dependencies = childInfo.toPackageReferences(
                     SCOPE_NAME_REQUIRE,
@@ -182,9 +180,6 @@ class Composer(
             )
         }
 
-        return packageReferences
-    }
-
     private fun parseProject(definitionFile: File, scopes: Set<Scope>): Project {
         logger.info { "Parsing project metadata from '$definitionFile'..." }