Memory leak in initPsiFileFactory (pinterest#1407)

* Explicitly dispose to (possibly) prevent a memory leak

Possibly closes pinterest#1216

CHANGELOG.md

@@ -30,6 +30,7 @@ This section is applicable when providing rules that depend on one or more value
 - Do not delete blank lines in KDoc (no-trailing-spaces) ([#1376](https://github.com/pinterest/ktlint/issues/1376))
 - Do not indent raw string literals that are not followed by either trimIndent() or trimMargin() (`indent`) ([#1375](https://github.com/pinterest/ktlint/issues/1375))
 - Revert remove unnecessary wildcard imports as introduced in Ktlint 0.43.0 (`no-unused-imports`) ([#1277](https://github.com/pinterest/ktlint/issues/1277)), ([#1393](https://github.com/pinterest/ktlint/issues/1393)), ([#1256](https://github.com/pinterest/ktlint/issues/1256))
+- (Possibly) resolve memory leak ([#1216](https://github.com/pinterest/ktlint/issues/1216))
 
 ### Changed
 - Print the rule id always in the PlainReporter ([#1121](https://github.com/pinterest/ktlint/issues/1121))

ktlint-core/src/main/kotlin/com/pinterest/ktlint/core/internal/KotlinPsiFileFactory.kt

@@ -55,16 +55,22 @@ internal fun initPsiFileFactory(isFromCli: Boolean): PsiFileFactory {
     }
 
     val disposable = Disposer.newDisposable()
-
-    val project = KotlinCoreEnvironment.createForProduction(
-        disposable,
-        compilerConfiguration,
-        EnvironmentConfigFiles.JVM_CONFIG_FILES
-    ).project as MockProject
-
-    project.enableASTMutations()
-
-    return PsiFileFactory.getInstance(project)
+    try {
+        val project = KotlinCoreEnvironment.createForProduction(
+            disposable,
+            compilerConfiguration,
+            EnvironmentConfigFiles.JVM_CONFIG_FILES
+        ).project as MockProject
+
+        project.enableASTMutations()
+
+        return PsiFileFactory.getInstance(project)
+    } finally {
+        // Dispose explicitly to (possibly) prevent memory leak
+        // https://discuss.kotlinlang.org/t/memory-leak-in-kotlincoreenvironment-and-kotlintojvmbytecodecompiler/21950
+        // https://youtrack.jetbrains.com/issue/KT-47044
+        disposable.dispose()
+    }
 }
 
 /**