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node_modules/metro-resolver/src/utils/isSubpathDefinedInExportsLike.js.flow

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+/**
+ * Identifies whether the given subpath is defined in the given "exports"-like
+ * mapping. Does not reduce exports conditions (therefore does not identify
+ * whether the subpath is mapped to a value).
+ */
+import type {NormalizedExportsLikeMap} from '../types';
+
+import {matchSubpathPattern} from './matchSubpathPattern';
+
+export function isSubpathDefinedInExportsLike(
+  exportsLikeMap: NormalizedExportsLikeMap,
+  subpath: string,
+): boolean {
+  if (exportsLikeMap.has(subpath)) {
+    return true;
+  }
+
+  // Attempt to match after expanding any subpath pattern keys
+  for (const key of exportsLikeMap.keys()) {
+    if (
+      key.split('*').length === 2 &&
+      matchSubpathPattern(key, subpath) != null
+    ) {
+      return true;
+    }
+  }
+
+  return false;
+}