From ec851ccf4f329bb6e629b6b48839f5345e18b86b Mon Sep 17 00:00:00 2001
From: Alex Hunt <huntie@meta.com>
Date: Tue, 4 Mar 2025 05:35:34 -0800
Subject: [PATCH] Simplify type source file resolution logic (#49785)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/49785

Changelog: [Internal]

Reviewed By: cipolleschi, iwoplaza

Differential Revision: D70487265

fbshipit-source-id: ed4654e975f5fec0fe76f8d5f156fef611e24d14
---
 scripts/build/build-types/buildTypes.js               |  9 ---------
 .../build/build-types/resolution/getDependencies.js   |  3 ++-
 .../build-types/resolution/resolveTypeInputFile.js    | 11 ++++++++++-
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/scripts/build/build-types/buildTypes.js b/scripts/build/build-types/buildTypes.js
index 5ea7cf623e0..1b1159e71bb 100644
--- a/scripts/build/build-types/buildTypes.js
+++ b/scripts/build/build-types/buildTypes.js
@@ -11,7 +11,6 @@
 
 const {PACKAGES_DIR, REPO_ROOT} = require('../../consts');
 const getRequireStack = require('./resolution/getRequireStack');
-const resolveTypeInputFile = require('./resolution/resolveTypeInputFile');
 const translatedModuleTemplate = require('./templates/translatedModule.d.ts-template');
 const translateSourceFile = require('./translateSourceFile');
 const {promises: fs} = require('fs');
@@ -103,14 +102,6 @@ async function buildTypes(): Promise<void> {
   const dependencyEdges: DependencyEdges = [];
 
   while (files.size > 0) {
-    for (const file of files) {
-      const interfaceFile = resolveTypeInputFile(file);
-      if (interfaceFile) {
-        files.delete(file);
-        translatedFiles.add(file);
-        files.add(interfaceFile);
-      }
-    }
     const dependencies = await translateSourceFiles(dependencyEdges, files);
     dependencyEdges.push(...dependencies);
 
diff --git a/scripts/build/build-types/resolution/getDependencies.js b/scripts/build/build-types/resolution/getDependencies.js
index 4baee42c509..15e78bd8dcc 100644
--- a/scripts/build/build-types/resolution/getDependencies.js
+++ b/scripts/build/build-types/resolution/getDependencies.js
@@ -12,6 +12,7 @@
 import type {DependencyContext} from './simpleResolve';
 import type {ParseResult} from 'hermes-transform/dist/transform/parse';
 
+const resolveTypeInputFile = require('./resolveTypeInputFile');
 const simpleResolve = require('./simpleResolve');
 const debug = require('debug')('build-types:resolution');
 const {traverse} = require('hermes-transform/dist/traverse/traverse');
@@ -82,7 +83,7 @@ async function getDependencies(
       );
 
       if (resolved != null) {
-        dependencies.add(resolved);
+        dependencies.add(resolveTypeInputFile(resolved) ?? resolved);
       }
     }),
   );
diff --git a/scripts/build/build-types/resolution/resolveTypeInputFile.js b/scripts/build/build-types/resolution/resolveTypeInputFile.js
index f35d6464768..a7ac87519cc 100644
--- a/scripts/build/build-types/resolution/resolveTypeInputFile.js
+++ b/scripts/build/build-types/resolution/resolveTypeInputFile.js
@@ -20,18 +20,25 @@ const TYPEDEF_MAPPING: Record<string, $ReadOnlyArray<string>> = {
   '.js': ['.js.flow'],
 };
 
+const cached = new Map<string, ?string>();
+
 /**
  * Resolve the Flow file defining the type interface for a given source file.
  *
  * Ensures common interface file (js.flow) or base implementation (.js) exists for
  * platform-specific files (.android.js or .ios.js).
  */
-function resolveTypeInputFile(file: string): string | null {
+function resolveTypeInputFile(file: string): ?string {
+  if (cached.has(file)) {
+    return cached.get(file);
+  }
+
   const [pathWithoutExt, extension] = splitPathAndExtension(file);
 
   const extsToCheck = TYPEDEF_MAPPING[extension];
 
   if (!extsToCheck) {
+    cached.set(file, null);
     return null;
   }
 
@@ -44,12 +51,14 @@ function resolveTypeInputFile(file: string): string | null {
         path.relative(REPO_ROOT, file),
         path.relative(REPO_ROOT, interfaceFile),
       );
+      cached.set(file, interfaceFile);
       return interfaceFile;
     }
   }
 
   if (extension === '.js') {
     // .js files do not require a common interface
+    cached.set(file, null);
     return null;
   }