From 29d565bb2e1be147d6f895ec2e105e23c5d9671b Mon Sep 17 00:00:00 2001
From: kamosama <837080904@qq.com>
Date: Sun, 27 Aug 2023 23:55:04 +0800
Subject: [PATCH 1/3] perf The module flattening function can reduce GC using
 MutableSet

---
 .../kotlin/org/koin/core/module/Module.kt       | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
index 9f95ac3d5..35465de4d 100644
--- a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
+++ b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
@@ -236,16 +236,17 @@ operator fun List<Module>.plus(module: Module): List<Module> = this + listOf(mod
  * Run through the module list to flatten all modules & submodules
  */
 @OptIn(KoinInternalApi::class)
-tailrec fun flatten(modules: List<Module>, newModules: Set<Module> = emptySet()): Set<Module> {
-    return if (modules.isEmpty()) {
-        newModules
-    } else {
-        val head = modules.first() ?: error("Flatten - No head element in list")
+tailrec fun flatten(modules: List<Module>, newModules: MutableSet<Module> = mutableSetOf()): Set<Module> {
+    if (modules.isNotEmpty()) {
+        val head = modules.first()
         val tail = modules.subList(1, modules.size)
-        if (head.includedModules.isEmpty()) {
-            flatten(tail, newModules + head)
+        newModules.add(head)
+        if (head.importedModules.isEmpty()) {
+            return flatten(tail, newModules)
         } else {
-            flatten(head.includedModules + tail, newModules + head)
+            return flatten(head.importedModules + tail, newModules)
         }
+    } else {
+        return newModules
     }
 }
\ No newline at end of file

From 50bfa99bf1b66972cb260f5f0c5d06e773ac88c4 Mon Sep 17 00:00:00 2001
From: kamosama <837080904@qq.com>
Date: Mon, 28 Aug 2023 13:55:10 +0800
Subject: [PATCH 2/3] perf The module flattening function can reduce GC using
 MutableSet

---
 .../commonMain/kotlin/org/koin/core/module/Module.kt   | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
index 35465de4d..422eef27d 100644
--- a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
+++ b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
@@ -237,16 +237,16 @@ operator fun List<Module>.plus(module: Module): List<Module> = this + listOf(mod
  */
 @OptIn(KoinInternalApi::class)
 tailrec fun flatten(modules: List<Module>, newModules: MutableSet<Module> = mutableSetOf()): Set<Module> {
-    if (modules.isNotEmpty()) {
+    return if (modules.isNotEmpty()) {
         val head = modules.first()
         val tail = modules.subList(1, modules.size)
         newModules.add(head)
-        if (head.importedModules.isEmpty()) {
-            return flatten(tail, newModules)
+        if (head.includedModules.isEmpty()) {
+            flatten(tail, newModules)
         } else {
-            return flatten(head.importedModules + tail, newModules)
+            flatten(head.includedModules + tail, newModules)
         }
     } else {
-        return newModules
+        newModules
     }
 }
\ No newline at end of file

From fe49b2780247232d144bf643ec184a2daa2ed3a6 Mon Sep 17 00:00:00 2001
From: kamosama <837080904@qq.com>
Date: Fri, 1 Sep 2023 18:13:24 +0800
Subject: [PATCH 3/3] perf The module flattening function  reduce GC  by
 removing 'tailrec' and using 'MutableSet'

---
 .../kotlin/org/koin/core/module/Module.kt       | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
index 422eef27d..2fa53edca 100644
--- a/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
+++ b/core/koin-core/src/commonMain/kotlin/org/koin/core/module/Module.kt
@@ -236,17 +236,12 @@ operator fun List<Module>.plus(module: Module): List<Module> = this + listOf(mod
  * Run through the module list to flatten all modules & submodules
  */
 @OptIn(KoinInternalApi::class)
-tailrec fun flatten(modules: List<Module>, newModules: MutableSet<Module> = mutableSetOf()): Set<Module> {
-    return if (modules.isNotEmpty()) {
-        val head = modules.first()
-        val tail = modules.subList(1, modules.size)
-        newModules.add(head)
-        if (head.includedModules.isEmpty()) {
-            flatten(tail, newModules)
-        } else {
-            flatten(head.includedModules + tail, newModules)
+fun flatten(modules: List<Module>): Set<Module> {
+    fun flat(modules: List<Module>, newModules: MutableSet<Module>){
+        modules.forEach{
+            newModules += it
+            flat(it.includedModules,newModules)
         }
-    } else {
-        newModules
     }
+    return mutableSetOf<Module>().apply { flat(modules,this) }
 }
\ No newline at end of file