From d8164960d21336d4a726d8179b314f05fe3aeb22 Mon Sep 17 00:00:00 2001
From: Brad Zacher <brad.zacher@gmail.com>
Date: Mon, 20 Feb 2023 17:29:28 +1030
Subject: [PATCH] feat(typescript-estree): expose a wrapper cache clearing
 function for advanced usecases (#6476)

---
 .gitignore                                    |  1 +
 .../typescript-estree/src/clear-caches.ts     | 21 +++++++++++++++++++
 packages/typescript-estree/src/index.ts       |  3 +--
 .../src/parseSettings/createParseSettings.ts  |  4 ++++
 .../src/parseSettings/resolveProjectList.ts   |  4 ++++
 5 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 packages/typescript-estree/src/clear-caches.ts

diff --git a/.gitignore b/.gitignore
index 0973f04542e..7fad8b15206 100644
--- a/.gitignore
+++ b/.gitignore
@@ -76,6 +76,7 @@ jspm_packages/
 .idea
 dist
 _ts3.4
+_ts4.2
 *.tsbuildinfo
 .watchmanconfig
 .rollup.cache
diff --git a/packages/typescript-estree/src/clear-caches.ts b/packages/typescript-estree/src/clear-caches.ts
new file mode 100644
index 00000000000..c223fe85275
--- /dev/null
+++ b/packages/typescript-estree/src/clear-caches.ts
@@ -0,0 +1,21 @@
+import { clearWatchCaches } from './create-program/getWatchProgramsForProjects';
+import { clearProgramCache as clearProgramCacheOriginal } from './parser';
+import { clearTSConfigMatchCache } from './parseSettings/createParseSettings';
+import { clearGlobCache } from './parseSettings/resolveProjectList';
+
+/**
+ * Clears all of the internal caches.
+ * Generally you shouldn't need or want to use this.
+ * Examples of intended uses:
+ * - In tests to reset parser state to keep tests isolated.
+ * - In custom lint tooling that iteratively lints one project at a time to prevent OOMs.
+ */
+export function clearCaches(): void {
+  clearProgramCacheOriginal();
+  clearWatchCaches();
+  clearTSConfigMatchCache();
+  clearGlobCache();
+}
+
+// TODO - delete this in next major
+export const clearProgramCache = clearCaches();
diff --git a/packages/typescript-estree/src/index.ts b/packages/typescript-estree/src/index.ts
index bc7ed6024f3..511ba6c769c 100644
--- a/packages/typescript-estree/src/index.ts
+++ b/packages/typescript-estree/src/index.ts
@@ -5,16 +5,15 @@ export {
   parseWithNodeMaps,
   ParseAndGenerateServicesResult,
   ParseWithNodeMapsResult,
-  clearProgramCache,
 } from './parser';
 export { ParserServices, TSESTreeOptions } from './parser-options';
 export { simpleTraverse } from './simple-traverse';
 export * from './ts-estree';
-export { clearWatchCaches as clearCaches } from './create-program/getWatchProgramsForProjects';
 export { createProgramFromConfigFile as createProgram } from './create-program/useProvidedPrograms';
 export * from './create-program/getScriptKind';
 export { typescriptVersionIsAtLeast } from './version-check';
 export * from './getModifiers';
+export * from './clear-caches';
 
 // re-export for backwards-compat
 export { visitorKeys } from '@typescript-eslint/visitor-keys';
diff --git a/packages/typescript-estree/src/parseSettings/createParseSettings.ts b/packages/typescript-estree/src/parseSettings/createParseSettings.ts
index 028088765a2..7518b0b686c 100644
--- a/packages/typescript-estree/src/parseSettings/createParseSettings.ts
+++ b/packages/typescript-estree/src/parseSettings/createParseSettings.ts
@@ -121,6 +121,10 @@ export function createParseSettings(
   return parseSettings;
 }
 
+export function clearTSConfigMatchCache(): void {
+  TSCONFIG_MATCH_CACHE?.clear();
+}
+
 /**
  * Ensures source code is a string.
  */
diff --git a/packages/typescript-estree/src/parseSettings/resolveProjectList.ts b/packages/typescript-estree/src/parseSettings/resolveProjectList.ts
index 72e9539d2b9..f9d935b88cd 100644
--- a/packages/typescript-estree/src/parseSettings/resolveProjectList.ts
+++ b/packages/typescript-estree/src/parseSettings/resolveProjectList.ts
@@ -21,6 +21,10 @@ const log = debug(
 let RESOLUTION_CACHE: ExpiringCache<string, readonly CanonicalPath[]> | null =
   null;
 
+export function clearGlobCache(): void {
+  RESOLUTION_CACHE?.clear();
+}
+
 /**
  * Normalizes, sanitizes, resolves and filters the provided project paths
  */