metro-resolver-symlinks support for metro 0.82 (#3920)

* Support for metro 0.82

* docs(changeset): Add support for metro 0.82

* Update packages/metro-resolver-symlinks/src/utils/metro.ts

Co-authored-by: Tommy Nguyen <[email protected]>

* review feedback

---------

Co-authored-by: Tommy Nguyen <[email protected]>

Author: acoates-ms

.changeset/chilly-rivers-fail.md

@@ -0,0 +1,5 @@
+---
+"@rnx-kit/metro-resolver-symlinks": patch
+---
+
+Add support for metro 0.82

packages/metro-resolver-symlinks/src/utils/metro.ts

@@ -25,7 +25,8 @@ function fileExists(path: string): boolean {
 function importMetroModule(path: string) {
   const modulePath = findMetroPath() + path;
   try {
-    return require(modulePath);
+    const mod = require(modulePath);
+    return mod.default ?? mod;
   } catch (_) {
     throw new Error(
       `Cannot find '${modulePath}'. This probably means that ` +
@@ -76,16 +77,22 @@ export function shouldEnableRetryResolvingFromDisk({
       return disableWithReason(
         `has not been tested with '${RETRY_FROM_DISK_FLAG}'`
       );
-    } else if (v > 81) {
-      return disableWithReason(
-        `should no longer need '${RETRY_FROM_DISK_FLAG}'`
-      );
     }
   }
 
   return Boolean(experimental_retryResolvingFromDisk);
 }
 
+function computeSha1(filePath: string): string {
+  // Paths generated by pnpm setups include version numbers and/or hashes
+  if (filePath.includes(".pnpm-store") || filePath.includes(".store")) {
+    return filePath;
+  }
+
+  const stat = fs.lstatSync(filePath);
+  return filePath + "|" + stat.mtime.toISOString();
+}
+
 /**
  * Monkey-patches Metro to not use HasteFS as the only source for module
  * resolution.
@@ -158,31 +165,51 @@ export function patchMetro(options: Options): void {
 
   // Since we will be resolving files outside of `watchFolders`, their hashes
   // will not be found. We'll return the `filePath` as they should be unique.
-  DependencyGraph.prototype.orig_getSha1 = DependencyGraph.prototype.getSha1;
-  DependencyGraph.prototype.getSha1 = function (filePath: string): string {
-    try {
-      return this.orig_getSha1(filePath);
-    } catch (e) {
-      // `ReferenceError` will always be thrown when Metro encounters a file
-      // that does not exist in the Haste map.
-      // In metro 0.81 (https://github.com/facebook/metro/pull/1435)
-      // this was changed to a standard `Error` - so verify the message
-      if (
-        e instanceof ReferenceError ||
-        (e instanceof Error && e.message.startsWith("Failed to get the SHA-1"))
-      ) {
-        // Paths generated by pnpm setups include version numbers and/or hashes
-        if (filePath.includes(".pnpm-store") || filePath.includes(".store")) {
-          return filePath;
+  // getSha1 was replaced with getOrComputeSha1 in metro 0.82 (https://github.com/facebook/metro/commit/e667aa3acd594d795bbab45c45107e7bc6322303)
+  if (DependencyGraph.prototype.getSha1) {
+    DependencyGraph.prototype.orig_getSha1 = DependencyGraph.prototype.getSha1;
+    DependencyGraph.prototype.getSha1 = function (filePath: string): string {
+      try {
+        return this.orig_getSha1(filePath);
+      } catch (e) {
+        // `ReferenceError` will always be thrown when Metro encounters a file
+        // that does not exist in the Haste map.
+        // In metro 0.81 (https://github.com/facebook/metro/pull/1435)
+        // this was changed to a standard `Error` - so verify the message
+        if (
+          e instanceof ReferenceError ||
+          (e instanceof Error &&
+            e.message.startsWith("Failed to get the SHA-1"))
+        ) {
+          return computeSha1(filePath);
         }
 
-        const stat = fs.lstatSync(filePath);
-        return filePath + "|" + stat.mtime.toISOString();
+        throw e;
       }
+    };
+  }
 
-      throw e;
-    }
-  };
+  // getSha1 was replaced with getOrComputeSha1 in metro 0.82 (https://github.com/facebook/metro/commit/e667aa3acd594d795bbab45c45107e7bc6322303)
+  if (DependencyGraph.prototype.getOrComputeSha1) {
+    DependencyGraph.prototype.orig_getOrComputeSha1 =
+      DependencyGraph.prototype.getOrComputeSha1;
+    DependencyGraph.prototype.getOrComputeSha1 = async function (
+      filePath: string
+    ): Promise<{ content?: Buffer; sha1: string }> {
+      try {
+        return await this.orig_getOrComputeSha1(filePath);
+      } catch (e) {
+        if (
+          e instanceof Error &&
+          e.message.startsWith("Failed to get the SHA-1")
+        ) {
+          return { sha1: computeSha1(filePath) };
+        }
+
+        throw e;
+      }
+    };
+  }
 
   // We need to patch `_processSingleAssetRequest` because it calls
   // `Assets.getAsset`, and `Assets.getAsset` checks whether the asset lives