From f0c1c39df7a611607616b5ba396291bf25aacf50 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Sun, 17 Dec 2023 20:53:45 +0100
Subject: [PATCH 01/20] Added inference of watchFolders from NPM/Yarn
 workspaces

---
 packages/metro-config/index.js     | 52 +++++++++++++++++++++++++++++-
 packages/metro-config/package.json |  1 +
 yarn.lock                          | 11 +++++++
 3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index 2abf2c8757d475..483be3955742b1 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -10,7 +10,10 @@
 
 /*:: import type {ConfigT} from 'metro-config'; */
 
+const fastGlob = require('fast-glob');
 const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
+const fs = require('node:fs');
+const path = require('node:path');
 
 const INTERNAL_CALLSITES_REGEX = new RegExp(
   [
@@ -36,6 +39,53 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
   ].join('|'),
 );
 
+/**
+ * Resolves the root of an NPM or Yarn workspace, by traversing the file tree upwards from a `candidatePath` in the search for
+ * - a directory with a package.json
+ * - which has a `workspaces` array of strings
+ * - which (possibly via a glob) includes the project root
+ * @param {string} projectRoot Project root to find a workspace root for
+ * @param {string | undefined} candidatePath Current path to search from
+ * @returns Path of a workspace root or `undefined`
+ */
+function getWorkspaceRoot(projectRoot, candidatePath = projectRoot) {
+  const packageJsonPath = path.resolve(candidatePath, 'package.json');
+  if (fs.existsSync(packageJsonPath)) {
+    try {
+      const { workspaces } = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
+      if (Array.isArray(workspaces)) {
+        // If one of the workspaces match the project root, this is the workspace root
+        // Note: While NPM workspaces doesn't currently support globs, Yarn does.
+        const matches = fastGlob.sync(workspaces, {
+          cwd: candidatePath,
+          onlyDirectories: true,
+          absolute: true,
+        });
+        if (matches.includes(projectRoot)) {
+          return candidatePath;
+        }
+      }
+    } catch (err) {
+      console.warn(`Failed reading or parsing ${packageJsonPath}:`, err);
+    }
+  }
+  // Try one level up
+  const parentDir = path.dirname(candidatePath);
+  if (parentDir !== candidatePath) {
+    return getWorkspaceRoot(projectRoot, parentDir);
+  } else {
+    return undefined;
+  }
+}
+
+/**
+ * Determine the watch folders
+ */
+function getWatchFolders(projectRoot) {
+  const workspaceRoot = getWorkspaceRoot(projectRoot);
+  return workspaceRoot ? [workspaceRoot] : [];
+}
+
 /**
  * Get the base Metro configuration for a React Native project.
  */
@@ -82,7 +132,7 @@ function getDefaultConfig(
         },
       }),
     },
-    watchFolders: [],
+    watchFolders: getWatchFolders(projectRoot),
   };
 
   // Set global hook so that the CLI can detect when this config has been loaded
diff --git a/packages/metro-config/package.json b/packages/metro-config/package.json
index 55016cb21ef010..0c09c6e0138968 100644
--- a/packages/metro-config/package.json
+++ b/packages/metro-config/package.json
@@ -22,6 +22,7 @@
   "dependencies": {
     "@react-native/js-polyfills": "0.74.0",
     "@react-native/metro-babel-transformer": "0.74.0",
+    "fast-glob": "^3.3.2",
     "metro-config": "^0.80.3",
     "metro-runtime": "^0.80.3"
   }
diff --git a/yarn.lock b/yarn.lock
index 0a96c50a30549d..f724d2947cfb25 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4954,6 +4954,17 @@ fast-glob@^3.2.9:
     merge2 "^1.3.0"
     micromatch "^4.0.4"
 
+fast-glob@^3.3.2:
+  version "3.3.2"
+  resolved "https://registry.yarnpkg.com/fast-glob/-/fast-glob-3.3.2.tgz#a904501e57cfdd2ffcded45e99a54fef55e46129"
+  integrity sha512-oX2ruAFQwf/Orj8m737Y5adxDQO0LAB7/S5MnxCdTNDd4p6BsyIVsv9JQsATbTSq8KHRpLwIHbVlUNatxd+1Ow==
+  dependencies:
+    "@nodelib/fs.stat" "^2.0.2"
+    "@nodelib/fs.walk" "^1.2.3"
+    glob-parent "^5.1.2"
+    merge2 "^1.3.0"
+    micromatch "^4.0.4"
+
 fast-json-patch@^3.0.0-1:
   version "3.1.1"
   resolved "https://registry.yarnpkg.com/fast-json-patch/-/fast-json-patch-3.1.1.tgz#85064ea1b1ebf97a3f7ad01e23f9337e72c66947"

From 5f08c430c1494afcd73b61c1595838489681444c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Mon, 18 Dec 2023 08:32:08 +0100
Subject: [PATCH 02/20] Adding flow types

---
 packages/metro-config/index.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index 483be3955742b1..ed73530fb06171 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -11,9 +11,9 @@
 /*:: import type {ConfigT} from 'metro-config'; */
 
 const fastGlob = require('fast-glob');
+const fs = require('fs');
 const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
-const fs = require('node:fs');
-const path = require('node:path');
+const path = require('path');
 
 const INTERNAL_CALLSITES_REGEX = new RegExp(
   [
@@ -48,7 +48,7 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
  * @param {string | undefined} candidatePath Current path to search from
  * @returns Path of a workspace root or `undefined`
  */
-function getWorkspaceRoot(projectRoot, candidatePath = projectRoot) {
+function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: string */ = projectRoot) /*: string | void */ {
   const packageJsonPath = path.resolve(candidatePath, 'package.json');
   if (fs.existsSync(packageJsonPath)) {
     try {
@@ -81,7 +81,7 @@ function getWorkspaceRoot(projectRoot, candidatePath = projectRoot) {
 /**
  * Determine the watch folders
  */
-function getWatchFolders(projectRoot) {
+function getWatchFolders(projectRoot /*: string */) {
   const workspaceRoot = getWorkspaceRoot(projectRoot);
   return workspaceRoot ? [workspaceRoot] : [];
 }

From e18e31ffa692eaa10da6273cce9199877d031d62 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Wed, 27 Dec 2023 20:06:18 +0100
Subject: [PATCH 03/20] Apply suggestions from code review

Co-authored-by: Rob Hogan <2590098+robhogan@users.noreply.github.com>
---
 packages/metro-config/index.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index ed73530fb06171..fc4673555b0242 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -45,12 +45,12 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
  * - which has a `workspaces` array of strings
  * - which (possibly via a glob) includes the project root
  * @param {string} projectRoot Project root to find a workspace root for
- * @param {string | undefined} candidatePath Current path to search from
+ * @param {string | null | undefined} candidatePath Current path to search from
  * @returns Path of a workspace root or `undefined`
  */
-function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: string */ = projectRoot) /*: string | void */ {
+function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: ?string */ = projectRoot) /*: ?string */ {
   const packageJsonPath = path.resolve(candidatePath, 'package.json');
-  if (fs.existsSync(packageJsonPath)) {
+  if (fs.accessSync(packageJsonPath, fs.constants.R_OK)) {
     try {
       const { workspaces } = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
       if (Array.isArray(workspaces)) {
@@ -74,7 +74,7 @@ function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: string */
   if (parentDir !== candidatePath) {
     return getWorkspaceRoot(projectRoot, parentDir);
   } else {
-    return undefined;
+    return null;
   }
 }
 

From 626625cfc0b10ee02b4e84ed67f79bd98b7524f2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Wed, 27 Dec 2023 21:06:46 +0100
Subject: [PATCH 04/20] Using micromatch and removed accessSync guard

---
 packages/metro-config/index.js     | 31 ++++++++++++++----------------
 packages/metro-config/package.json |  4 ++--
 yarn.lock                          | 23 ++++++++++------------
 3 files changed, 26 insertions(+), 32 deletions(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index fc4673555b0242..d51168b0529fa1 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -10,9 +10,9 @@
 
 /*:: import type {ConfigT} from 'metro-config'; */
 
-const fastGlob = require('fast-glob');
 const fs = require('fs');
 const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
+const micromatch = require('micromatch');
 const path = require('path');
 
 const INTERNAL_CALLSITES_REGEX = new RegExp(
@@ -50,22 +50,19 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
  */
 function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: ?string */ = projectRoot) /*: ?string */ {
   const packageJsonPath = path.resolve(candidatePath, 'package.json');
-  if (fs.accessSync(packageJsonPath, fs.constants.R_OK)) {
-    try {
-      const { workspaces } = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
-      if (Array.isArray(workspaces)) {
-        // If one of the workspaces match the project root, this is the workspace root
-        // Note: While NPM workspaces doesn't currently support globs, Yarn does.
-        const matches = fastGlob.sync(workspaces, {
-          cwd: candidatePath,
-          onlyDirectories: true,
-          absolute: true,
-        });
-        if (matches.includes(projectRoot)) {
-          return candidatePath;
-        }
+  try {
+    // If the access sync succeeds, it's safe to read the file
+    const { workspaces } = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
+    if (Array.isArray(workspaces)) {
+      // If one of the workspaces match the project root, this is the workspace root
+      // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
+      const relativePath = path.relative(candidatePath, projectRoot);
+      if (micromatch.isMatch(relativePath, workspaces)) {
+        return candidatePath;
       }
-    } catch (err) {
+    }
+  } catch (err) {
+    if (err.code !== 'ENOENT') {
       console.warn(`Failed reading or parsing ${packageJsonPath}:`, err);
     }
   }
@@ -144,4 +141,4 @@ function getDefaultConfig(
   );
 }
 
-module.exports = {getDefaultConfig, mergeConfig};
+module.exports = {getDefaultConfig, mergeConfig, getWorkspaceRoot};
diff --git a/packages/metro-config/package.json b/packages/metro-config/package.json
index 0c09c6e0138968..177924be399a92 100644
--- a/packages/metro-config/package.json
+++ b/packages/metro-config/package.json
@@ -22,8 +22,8 @@
   "dependencies": {
     "@react-native/js-polyfills": "0.74.0",
     "@react-native/metro-babel-transformer": "0.74.0",
-    "fast-glob": "^3.3.2",
     "metro-config": "^0.80.3",
-    "metro-runtime": "^0.80.3"
+    "metro-runtime": "^0.80.3",
+    "micromatch": "^4.0.5"
   }
 }
diff --git a/yarn.lock b/yarn.lock
index f724d2947cfb25..1e9761e28cd365 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3633,7 +3633,7 @@ brace-expansion@^2.0.1:
   dependencies:
     balanced-match "^1.0.0"
 
-braces@^3.0.1, braces@~3.0.2:
+braces@^3.0.1, braces@^3.0.2, braces@~3.0.2:
   version "3.0.2"
   resolved "https://registry.yarnpkg.com/braces/-/braces-3.0.2.tgz#3454e1a462ee8d599e236df336cd9ea4f8afe107"
   integrity sha512-b8um+L1RzM3WDSzvhm6gIz1yfTbBt6YTlcEKAvsmqCZZFw46z626lVj9j1yEPW33H5H+lBQpZMP1k8l+78Ha0A==
@@ -4954,17 +4954,6 @@ fast-glob@^3.2.9:
     merge2 "^1.3.0"
     micromatch "^4.0.4"
 
-fast-glob@^3.3.2:
-  version "3.3.2"
-  resolved "https://registry.yarnpkg.com/fast-glob/-/fast-glob-3.3.2.tgz#a904501e57cfdd2ffcded45e99a54fef55e46129"
-  integrity sha512-oX2ruAFQwf/Orj8m737Y5adxDQO0LAB7/S5MnxCdTNDd4p6BsyIVsv9JQsATbTSq8KHRpLwIHbVlUNatxd+1Ow==
-  dependencies:
-    "@nodelib/fs.stat" "^2.0.2"
-    "@nodelib/fs.walk" "^1.2.3"
-    glob-parent "^5.1.2"
-    merge2 "^1.3.0"
-    micromatch "^4.0.4"
-
 fast-json-patch@^3.0.0-1:
   version "3.1.1"
   resolved "https://registry.yarnpkg.com/fast-json-patch/-/fast-json-patch-3.1.1.tgz#85064ea1b1ebf97a3f7ad01e23f9337e72c66947"
@@ -7260,6 +7249,14 @@ micromatch@^4.0.4:
     braces "^3.0.1"
     picomatch "^2.2.3"
 
+micromatch@^4.0.5:
+  version "4.0.5"
+  resolved "https://registry.yarnpkg.com/micromatch/-/micromatch-4.0.5.tgz#bc8999a7cbbf77cdc89f132f6e467051b49090c6"
+  integrity sha512-DMy+ERcEW2q8Z2Po+WNXuw3c5YaUSFjAO5GsJqfEl7UjvtIuFKO6ZrKvcItdy98dwFI2N1tg3zNIdKaQT+aNdA==
+  dependencies:
+    braces "^3.0.2"
+    picomatch "^2.3.1"
+
 mime-db@1.52.0, "mime-db@>= 1.36.0 < 2":
   version "1.52.0"
   resolved "https://registry.yarnpkg.com/mime-db/-/mime-db-1.52.0.tgz#bbabcdc02859f4987301c856e3387ce5ec43bf70"
@@ -7826,7 +7823,7 @@ picocolors@^1.0.0:
   resolved "https://registry.yarnpkg.com/picocolors/-/picocolors-1.0.0.tgz#cb5bdc74ff3f51892236eaf79d68bc44564ab81c"
   integrity sha512-1fygroTLlHu66zi26VoTDv8yRgm0Fccecssto+MhsZ0D/DGW2sm8E8AjW7NU5VVTRt5GxbeZ5qBuJr+HyLYkjQ==
 
-picomatch@^2.0.4, picomatch@^2.2.1, picomatch@^2.2.3:
+picomatch@^2.0.4, picomatch@^2.2.1, picomatch@^2.2.3, picomatch@^2.3.1:
   version "2.3.1"
   resolved "https://registry.yarnpkg.com/picomatch/-/picomatch-2.3.1.tgz#3ba3833733646d9d3e4995946c1365a67fb07a42"
   integrity sha512-JU3teHTNjmE2VCGFzuY8EXzCDVwEqB2a8fsIvwaStHhAWJEeVd1o1QD80CU6+ZdEXXSLbSsuLwJjkCBWqRQUVA==

From 4afbf761dacd323b341c73f4b3a52fb7154bb58e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Wed, 27 Dec 2023 21:06:53 +0100
Subject: [PATCH 05/20] Adding tests

---
 .../__tests__/get-workspace-root-test.js      | 70 +++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 packages/metro-config/__tests__/get-workspace-root-test.js

diff --git a/packages/metro-config/__tests__/get-workspace-root-test.js b/packages/metro-config/__tests__/get-workspace-root-test.js
new file mode 100644
index 00000000000000..41b52d7c1a273e
--- /dev/null
+++ b/packages/metro-config/__tests__/get-workspace-root-test.js
@@ -0,0 +1,70 @@
+const { getWorkspaceRoot } = require('..');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+
+function createTempPackage(packageJson, packagePath = fs.mkdtempSync(path.join(os.tmpdir(), 'rn-metro-config-test-'))) {
+  fs.mkdirSync(packagePath, { recursive: true });
+  if (typeof packageJson === 'object') {
+    fs.writeFileSync(path.join(packagePath, 'package.json'), JSON.stringify(packageJson), 'utf8');
+  }
+  return packagePath;
+}
+
+describe('getWorkspaceRoot', () => {
+  test('returns null if not in a workspace', () => {
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    });
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(null);
+  });
+
+  test('supports an NPM workspace', () => {
+    const tempWorkspaceRootPath = createTempPackage({
+      name: 'package-root',
+      workspaces: ['packages/my-app', 'packages/my-lib'],
+    });
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
+  });
+
+  test('supports a Yarn workspace', () => {
+    const tempWorkspaceRootPath = createTempPackage({
+      name: 'package-root',
+      workspaces: ['packages/*'],
+    });
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
+  });
+
+  test.skip('supports a pnpm workspace', () => {
+    const tempWorkspaceRootPath = createTempPackage({
+      name: 'package-root',
+    });
+    // Create the pnpm workspace configuration (see https://pnpm.io/pnpm-workspace_yaml)
+    const workspacesConfig = 'packages: ["packages/*"]';
+    fs.writeFileSync(path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'), workspacesConfig, 'utf8');
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
+  });
+
+  test.skip('supports a pnpm workspace exclusion', () => {
+    const tempWorkspaceRootPath = createTempPackage({
+      name: 'package-root',
+    });
+    // Create the pnpm workspace configuration (see https://pnpm.io/pnpm-workspace_yaml)
+    const workspacesConfig = 'packages: ["packages/*", "!packages/*-app"]';
+    fs.writeFileSync(path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'), workspacesConfig, 'utf8');
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(null);
+  });
+});
+

From f27979c88218a6751af289f7eaabb5564fa8731c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Wed, 27 Dec 2023 21:10:15 +0100
Subject: [PATCH 06/20] Fixed flow type

---
 packages/metro-config/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index d51168b0529fa1..91b75c5f5e1d5d 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -48,7 +48,7 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
  * @param {string | null | undefined} candidatePath Current path to search from
  * @returns Path of a workspace root or `undefined`
  */
-function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: ?string */ = projectRoot) /*: ?string */ {
+function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: string */ = projectRoot) /*: ?string */ {
   const packageJsonPath = path.resolve(candidatePath, 'package.json');
   try {
     // If the access sync succeeds, it's safe to read the file

From 395b2d9d56898572957d2deb267dab525c54068c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 28 Dec 2023 19:56:18 +0100
Subject: [PATCH 07/20] Moved code to the cli-plugin package

---
 packages/community-cli-plugin/package.json    |  1 +
 .../utils/__tests__/getWorkspaceRoot-test.js} |  2 +-
 .../src/utils/getWorkspaceRoot.js             | 50 ++++++++++++++++++
 packages/metro-config/index.js                | 51 +------------------
 packages/metro-config/package.json            |  3 +-
 5 files changed, 55 insertions(+), 52 deletions(-)
 rename packages/{metro-config/__tests__/get-workspace-root-test.js => community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js} (97%)
 create mode 100644 packages/community-cli-plugin/src/utils/getWorkspaceRoot.js

diff --git a/packages/community-cli-plugin/package.json b/packages/community-cli-plugin/package.json
index 20a2be8d5fd6a7..580f3263b51e7f 100644
--- a/packages/community-cli-plugin/package.json
+++ b/packages/community-cli-plugin/package.json
@@ -31,6 +31,7 @@
     "metro": "^0.80.3",
     "metro-config": "^0.80.3",
     "metro-core": "^0.80.3",
+    "micromatch": "^4.0.5",
     "node-fetch": "^2.2.0",
     "querystring": "^0.2.1",
     "readline": "^1.3.0"
diff --git a/packages/metro-config/__tests__/get-workspace-root-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
similarity index 97%
rename from packages/metro-config/__tests__/get-workspace-root-test.js
rename to packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index 41b52d7c1a273e..6c41c521c87e42 100644
--- a/packages/metro-config/__tests__/get-workspace-root-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -1,4 +1,4 @@
-const { getWorkspaceRoot } = require('..');
+const { getWorkspaceRoot } = require('../getWorkspaceRoot');
 const fs = require('node:fs');
 const os = require('node:os');
 const path = require('node:path');
diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
new file mode 100644
index 00000000000000..8fa380cefd4f0d
--- /dev/null
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -0,0 +1,50 @@
+/**
+ * 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
+ */
+
+const fs = require('fs');
+const micromatch = require('micromatch');
+const path = require('path');
+
+/**
+ * Resolves the root of an NPM or Yarn workspace, by traversing the file tree upwards from a `candidatePath` in the search for
+ * - a directory with a package.json
+ * - which has a `workspaces` array of strings
+ * - which (possibly via a glob) includes the project root
+ */
+export function getWorkspaceRoot(
+  projectRoot /*: string */,
+  candidatePath /*: string */ = projectRoot,
+) /*: ?string */ {
+  const packageJsonPath = path.resolve(candidatePath, 'package.json');
+  try {
+    // If the access sync succeeds, it's safe to read the file
+    const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
+    if (Array.isArray(workspaces)) {
+      // If one of the workspaces match the project root, this is the workspace root
+      // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
+      const relativePath = path.relative(candidatePath, projectRoot);
+      if (micromatch.isMatch(relativePath, workspaces)) {
+        return candidatePath;
+      }
+    }
+  } catch (err) {
+    if (err.code !== 'ENOENT') {
+      console.warn(`Failed reading or parsing ${packageJsonPath}:`, err);
+    }
+  }
+  // Try one level up
+  const parentDir = path.dirname(candidatePath);
+  if (parentDir !== candidatePath) {
+    return getWorkspaceRoot(projectRoot, parentDir);
+  } else {
+    return null;
+  }
+}
diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index 91b75c5f5e1d5d..2abf2c8757d475 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -10,10 +10,7 @@
 
 /*:: import type {ConfigT} from 'metro-config'; */
 
-const fs = require('fs');
 const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
-const micromatch = require('micromatch');
-const path = require('path');
 
 const INTERNAL_CALLSITES_REGEX = new RegExp(
   [
@@ -39,50 +36,6 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
   ].join('|'),
 );
 
-/**
- * Resolves the root of an NPM or Yarn workspace, by traversing the file tree upwards from a `candidatePath` in the search for
- * - a directory with a package.json
- * - which has a `workspaces` array of strings
- * - which (possibly via a glob) includes the project root
- * @param {string} projectRoot Project root to find a workspace root for
- * @param {string | null | undefined} candidatePath Current path to search from
- * @returns Path of a workspace root or `undefined`
- */
-function getWorkspaceRoot(projectRoot /*: string */, candidatePath /*: string */ = projectRoot) /*: ?string */ {
-  const packageJsonPath = path.resolve(candidatePath, 'package.json');
-  try {
-    // If the access sync succeeds, it's safe to read the file
-    const { workspaces } = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
-    if (Array.isArray(workspaces)) {
-      // If one of the workspaces match the project root, this is the workspace root
-      // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
-      const relativePath = path.relative(candidatePath, projectRoot);
-      if (micromatch.isMatch(relativePath, workspaces)) {
-        return candidatePath;
-      }
-    }
-  } catch (err) {
-    if (err.code !== 'ENOENT') {
-      console.warn(`Failed reading or parsing ${packageJsonPath}:`, err);
-    }
-  }
-  // Try one level up
-  const parentDir = path.dirname(candidatePath);
-  if (parentDir !== candidatePath) {
-    return getWorkspaceRoot(projectRoot, parentDir);
-  } else {
-    return null;
-  }
-}
-
-/**
- * Determine the watch folders
- */
-function getWatchFolders(projectRoot /*: string */) {
-  const workspaceRoot = getWorkspaceRoot(projectRoot);
-  return workspaceRoot ? [workspaceRoot] : [];
-}
-
 /**
  * Get the base Metro configuration for a React Native project.
  */
@@ -129,7 +82,7 @@ function getDefaultConfig(
         },
       }),
     },
-    watchFolders: getWatchFolders(projectRoot),
+    watchFolders: [],
   };
 
   // Set global hook so that the CLI can detect when this config has been loaded
@@ -141,4 +94,4 @@ function getDefaultConfig(
   );
 }
 
-module.exports = {getDefaultConfig, mergeConfig, getWorkspaceRoot};
+module.exports = {getDefaultConfig, mergeConfig};
diff --git a/packages/metro-config/package.json b/packages/metro-config/package.json
index 177924be399a92..55016cb21ef010 100644
--- a/packages/metro-config/package.json
+++ b/packages/metro-config/package.json
@@ -23,7 +23,6 @@
     "@react-native/js-polyfills": "0.74.0",
     "@react-native/metro-babel-transformer": "0.74.0",
     "metro-config": "^0.80.3",
-    "metro-runtime": "^0.80.3",
-    "micromatch": "^4.0.5"
+    "metro-runtime": "^0.80.3"
   }
 }

From 6c91b224898f387898cdaf57bc67a32f72aa5ae8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 28 Dec 2023 20:48:56 +0100
Subject: [PATCH 08/20] Using getWorkspaceRoot to supply watchFolders as a
 fallback

---
 .../community-cli-plugin/src/utils/getWorkspaceRoot.js |  2 +-
 .../community-cli-plugin/src/utils/loadMetroConfig.js  | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index 8fa380cefd4f0d..c2d677722f33f7 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -4,7 +4,7 @@
  * 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
+ * @flow
  * @format
  * @oncall react_native
  */
diff --git a/packages/community-cli-plugin/src/utils/loadMetroConfig.js b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
index 44d0d275cb0e64..d0befb3785bb58 100644
--- a/packages/community-cli-plugin/src/utils/loadMetroConfig.js
+++ b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
@@ -12,6 +12,7 @@
 import type {Config} from '@react-native-community/cli-types';
 import type {ConfigT, InputConfigT, YargArguments} from 'metro-config';
 
+import {getWorkspaceRoot} from './getWorkspaceRoot';
 import {reactNativePlatformResolver} from './metroPlatformResolver';
 import {CLIError, logger} from '@react-native-community/cli-tools';
 import {loadConfig, mergeConfig, resolveConfig} from 'metro-config';
@@ -26,6 +27,11 @@ export type ConfigLoadingContext = $ReadOnly<{
   ...
 }>;
 
+function getWatchFolders(projectRoot: string) {
+  const workspaceRoot = getWorkspaceRoot(projectRoot);
+  return typeof workspaceRoot === 'string' ? [workspaceRoot] : undefined;
+}
+
 /**
  * Get the config options to override based on RN CLI inputs.
  */
@@ -70,6 +76,10 @@ function getOverrideConfig(
         ),
       ],
     },
+    watchFolders:
+      typeof config.watchFolders === 'undefined'
+        ? getWatchFolders(ctx.root)
+        : undefined,
   };
 }
 

From e4b8f9b21011ff2eeb314f2620cc4e4ab00e7d72 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 28 Dec 2023 21:45:37 +0100
Subject: [PATCH 09/20] Provide the watchFolders override property only if
 project had no watch folders

---
 .../src/utils/loadMetroConfig.js                     | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/loadMetroConfig.js b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
index d0befb3785bb58..de75e8565b27f7 100644
--- a/packages/community-cli-plugin/src/utils/loadMetroConfig.js
+++ b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
@@ -59,7 +59,7 @@ function getOverrideConfig(
     );
   }
 
-  return {
+  const overrides: InputConfigT = {
     resolver,
     serializer: {
       // We can include multiple copies of InitializeCore here because metro will
@@ -76,11 +76,13 @@ function getOverrideConfig(
         ),
       ],
     },
-    watchFolders:
-      typeof config.watchFolders === 'undefined'
-        ? getWatchFolders(ctx.root)
-        : undefined,
   };
+
+  if (config.watchFolders.length === 0) {
+    overrides.watchFolders = getWatchFolders(ctx.root);
+  }
+
+  return overrides;
 }
 
 /**

From 9f93c7b0ebac3ccafc942fb4a883dbe2727054d8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 28 Dec 2023 22:25:45 +0100
Subject: [PATCH 10/20] Appending workspace root as watch folder only if not
 other folder than the project root was given

---
 .../src/utils/loadMetroConfig.js                   | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/loadMetroConfig.js b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
index de75e8565b27f7..b233b873252c62 100644
--- a/packages/community-cli-plugin/src/utils/loadMetroConfig.js
+++ b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
@@ -27,11 +27,6 @@ export type ConfigLoadingContext = $ReadOnly<{
   ...
 }>;
 
-function getWatchFolders(projectRoot: string) {
-  const workspaceRoot = getWorkspaceRoot(projectRoot);
-  return typeof workspaceRoot === 'string' ? [workspaceRoot] : undefined;
-}
-
 /**
  * Get the config options to override based on RN CLI inputs.
  */
@@ -78,8 +73,13 @@ function getOverrideConfig(
     },
   };
 
-  if (config.watchFolders.length === 0) {
-    overrides.watchFolders = getWatchFolders(ctx.root);
+  // Applying the heuristic of appending workspace root as watch folder,
+  // only if no other watch folder (beside the project root) has been given.
+  if (!config.watchFolders.some(folder => folder !== ctx.root)) {
+    const workspaceRoot = getWorkspaceRoot(ctx.root);
+    if (typeof workspaceRoot === 'string') {
+      overrides.watchFolders = [...config.watchFolders, workspaceRoot];
+    }
   }
 
   return overrides;

From 43594bd23badad98e35a8357a54e13481771340a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Fri, 29 Dec 2023 20:16:44 +0100
Subject: [PATCH 11/20] Adding support for an alternative way for Yarn to
 declare workspaces

---
 .../utils/__tests__/getWorkspaceRoot-test.js  | 13 +++++++
 .../src/utils/getWorkspaceRoot.js             | 38 +++++++++++++------
 2 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index 6c41c521c87e42..f42337d85277a7 100644
--- a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -41,6 +41,19 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
+  test('supports a Yarn workspace (object style)', () => {
+    const tempWorkspaceRootPath = createTempPackage({
+      name: 'package-root',
+      workspaces: {
+        packages: ['packages/*'],
+      },
+    });
+    const tempPackagePath = createTempPackage({
+      name: 'my-app',
+    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
+  });
+
   test.skip('supports a pnpm workspace', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index c2d677722f33f7..2e5fd3f1aa4fab 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -13,6 +13,26 @@ const fs = require('fs');
 const micromatch = require('micromatch');
 const path = require('path');
 
+/**
+ * Get the workspace paths from the path of a potential workspace root.
+ */
+function getWorkspacePaths(packagePath /*: string */) /*: string[] */ {
+  const packageJsonPath = path.resolve(packagePath, 'package.json');
+  const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
+  if (Array.isArray(workspaces)) {
+    return workspaces;
+  } else if (
+    typeof workspaces === 'object' &&
+    Array.isArray(workspaces.packages)
+  ) {
+    // An alternative way for Yarn to declare workspace packages
+    return workspaces.packages;
+  } else {
+    return [];
+  }
+  // TODO: Support PNPN workspaces
+}
+
 /**
  * Resolves the root of an NPM or Yarn workspace, by traversing the file tree upwards from a `candidatePath` in the search for
  * - a directory with a package.json
@@ -23,21 +43,17 @@ export function getWorkspaceRoot(
   projectRoot /*: string */,
   candidatePath /*: string */ = projectRoot,
 ) /*: ?string */ {
-  const packageJsonPath = path.resolve(candidatePath, 'package.json');
   try {
-    // If the access sync succeeds, it's safe to read the file
-    const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
-    if (Array.isArray(workspaces)) {
-      // If one of the workspaces match the project root, this is the workspace root
-      // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
-      const relativePath = path.relative(candidatePath, projectRoot);
-      if (micromatch.isMatch(relativePath, workspaces)) {
-        return candidatePath;
-      }
+    const workspacePaths = getWorkspacePaths(candidatePath);
+    // If one of the workspaces match the project root, this is the workspace root
+    // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
+    const relativePath = path.relative(candidatePath, projectRoot);
+    if (micromatch.isMatch(relativePath, workspacePaths)) {
+      return candidatePath;
     }
   } catch (err) {
     if (err.code !== 'ENOENT') {
-      console.warn(`Failed reading or parsing ${packageJsonPath}:`, err);
+      console.warn(`Failed getting workspace root from ${candidatePath}:`, err);
     }
   }
   // Try one level up

From 8a734bfd0788bb793d2942b09c262773376c34d5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Fri, 29 Dec 2023 21:01:38 +0100
Subject: [PATCH 12/20] Adding support for PNPM workspaces

---
 packages/community-cli-plugin/package.json    |  3 +-
 .../utils/__tests__/getWorkspaceRoot-test.js  |  4 +-
 .../src/utils/getWorkspaceRoot.js             | 68 ++++++++++++-------
 yarn.lock                                     |  5 ++
 4 files changed, 52 insertions(+), 28 deletions(-)

diff --git a/packages/community-cli-plugin/package.json b/packages/community-cli-plugin/package.json
index 580f3263b51e7f..42ac73ae2a6240 100644
--- a/packages/community-cli-plugin/package.json
+++ b/packages/community-cli-plugin/package.json
@@ -34,7 +34,8 @@
     "micromatch": "^4.0.5",
     "node-fetch": "^2.2.0",
     "querystring": "^0.2.1",
-    "readline": "^1.3.0"
+    "readline": "^1.3.0",
+    "yaml": "^2.3.4"
   },
   "devDependencies": {
     "metro-resolver": "^0.80.3"
diff --git a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index f42337d85277a7..3bdc5c0312be68 100644
--- a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -54,7 +54,7 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
-  test.skip('supports a pnpm workspace', () => {
+  test('supports a pnpm workspace', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
     });
@@ -67,7 +67,7 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
-  test.skip('supports a pnpm workspace exclusion', () => {
+  test('supports a pnpm workspace exclusion', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
     });
diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index 2e5fd3f1aa4fab..34061521f70f9f 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -12,25 +12,48 @@
 const fs = require('fs');
 const micromatch = require('micromatch');
 const path = require('path');
+const yaml = require('yaml');
 
 /**
  * Get the workspace paths from the path of a potential workspace root.
+ *
+ * This supports:
+ * - [NPM workspaces](https://docs.npmjs.com/cli/v10/using-npm/workspaces)
+ * - [Yarn workspaces](https://yarnpkg.com/features/workspaces)
+ * - [PNPM workspaces](https://pnpm.io/workspaces)
  */
 function getWorkspacePaths(packagePath /*: string */) /*: string[] */ {
-  const packageJsonPath = path.resolve(packagePath, 'package.json');
-  const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
-  if (Array.isArray(workspaces)) {
-    return workspaces;
-  } else if (
-    typeof workspaces === 'object' &&
-    Array.isArray(workspaces.packages)
-  ) {
-    // An alternative way for Yarn to declare workspace packages
-    return workspaces.packages;
-  } else {
-    return [];
+  const result /*: string[] */ = [];
+  try {
+    const packageJsonPath = path.resolve(packagePath, 'package.json');
+    const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
+    if (Array.isArray(workspaces)) {
+      result.push(...workspaces);
+    } else if (
+      typeof workspaces === 'object' &&
+      Array.isArray(workspaces.packages)
+    ) {
+      // An alternative way for Yarn to declare workspace packages
+      result.push(...workspaces.packages);
+    }
+    // Falling back to PNPN workspaces
+    const pnpmWorkspacePath = path.resolve(packagePath, 'pnpm-workspace.yaml');
+    const pnpmWorkspaceConfig = yaml.parse(
+      fs.readFileSync(pnpmWorkspacePath, 'utf8'),
+    );
+    if (
+      typeof pnpmWorkspaceConfig === 'object' &&
+      Array.isArray(pnpmWorkspaceConfig.packages)
+    ) {
+      result.push(...pnpmWorkspaceConfig.packages);
+    }
+  } catch (err) {
+    if (err.code !== 'ENOENT') {
+      console.warn(`Failed getting workspace root from ${packagePath}:`, err);
+    }
+  } finally {
+    return result;
   }
-  // TODO: Support PNPN workspaces
 }
 
 /**
@@ -43,18 +66,13 @@ export function getWorkspaceRoot(
   projectRoot /*: string */,
   candidatePath /*: string */ = projectRoot,
 ) /*: ?string */ {
-  try {
-    const workspacePaths = getWorkspacePaths(candidatePath);
-    // If one of the workspaces match the project root, this is the workspace root
-    // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
-    const relativePath = path.relative(candidatePath, projectRoot);
-    if (micromatch.isMatch(relativePath, workspacePaths)) {
-      return candidatePath;
-    }
-  } catch (err) {
-    if (err.code !== 'ENOENT') {
-      console.warn(`Failed getting workspace root from ${candidatePath}:`, err);
-    }
+  const workspacePaths = getWorkspacePaths(candidatePath);
+  // If one of the workspaces match the project root, this is the workspace root
+  // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
+  const relativePath = path.relative(candidatePath, projectRoot);
+  // Using this instead of `micromatch.isMatch` to enable excluding patterns
+  if (micromatch([relativePath], workspacePaths).length > 0) {
+    return candidatePath;
   }
   // Try one level up
   const parentDir = path.dirname(candidatePath);
diff --git a/yarn.lock b/yarn.lock
index 1e9761e28cd365..ef916208636458 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -9594,6 +9594,11 @@ yaml@^2.2.1:
   resolved "https://registry.yarnpkg.com/yaml/-/yaml-2.3.1.tgz#02fe0975d23cd441242aa7204e09fc28ac2ac33b"
   integrity sha512-2eHWfjaoXgTBC2jNM1LRef62VQa0umtvRiDSk6HSzW7RvS5YtkabJrwYLLEKWBc8a5U2PTSCs+dJjUTJdlHsWQ==
 
+yaml@^2.3.4:
+  version "2.3.4"
+  resolved "https://registry.yarnpkg.com/yaml/-/yaml-2.3.4.tgz#53fc1d514be80aabf386dc6001eb29bf3b7523b2"
+  integrity sha512-8aAvwVUSHpfEqTQ4w/KMlf3HcRdt50E5ODIQJBw1fQ5RL34xabzxtUlzTXVqc4rkZsPbvrXKWnABCD7kWSmocA==
+
 yargs-parser@^18.1.2:
   version "18.1.3"
   resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-18.1.3.tgz#be68c4975c6b2abf469236b0c870362fab09a7b0"

From 2059ac2ce7a4f2e915805e921c7c3c437d1ae790 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Tue, 2 Jan 2024 15:27:45 +0100
Subject: [PATCH 13/20] Apply suggestions from code review

Co-authored-by: Alex Hunt <hello@alexhunt.io>
---
 .../community-cli-plugin/src/utils/getWorkspaceRoot.js    | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index 34061521f70f9f..86c951312ae13c 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -22,7 +22,7 @@ const yaml = require('yaml');
  * - [Yarn workspaces](https://yarnpkg.com/features/workspaces)
  * - [PNPM workspaces](https://pnpm.io/workspaces)
  */
-function getWorkspacePaths(packagePath /*: string */) /*: string[] */ {
+function getWorkspacePaths(packagePath: string): Array<string> {
   const result /*: string[] */ = [];
   try {
     const packageJsonPath = path.resolve(packagePath, 'package.json');
@@ -57,7 +57,8 @@ function getWorkspacePaths(packagePath /*: string */) /*: string[] */ {
 }
 
 /**
- * Resolves the root of an NPM or Yarn workspace, by traversing the file tree upwards from a `candidatePath` in the search for
+ * Resolves the root of an npm or Yarn workspace, by traversing the file tree
+ * upwards from a `candidatePath` in the search for
  * - a directory with a package.json
  * - which has a `workspaces` array of strings
  * - which (possibly via a glob) includes the project root
@@ -78,7 +79,6 @@ export function getWorkspaceRoot(
   const parentDir = path.dirname(candidatePath);
   if (parentDir !== candidatePath) {
     return getWorkspaceRoot(projectRoot, parentDir);
-  } else {
-    return null;
   }
+  return null;
 }

From eca58a6f15543aa01798e3dae3f291cfea58725d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Tue, 2 Jan 2024 15:39:36 +0100
Subject: [PATCH 14/20] Turned test file to flow

---
 .../utils/__tests__/getWorkspaceRoot-test.js  | 92 ++++++++++++++-----
 1 file changed, 67 insertions(+), 25 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index 3bdc5c0312be68..1eb20cf7ceda01 100644
--- a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -1,12 +1,32 @@
-const { getWorkspaceRoot } = require('../getWorkspaceRoot');
-const fs = require('node:fs');
-const os = require('node:os');
-const path = require('node:path');
+/**
+ * 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
+ */
 
-function createTempPackage(packageJson, packagePath = fs.mkdtempSync(path.join(os.tmpdir(), 'rn-metro-config-test-'))) {
-  fs.mkdirSync(packagePath, { recursive: true });
+const {getWorkspaceRoot} = require('../getWorkspaceRoot');
+const fs = require('fs');
+const os = require('os');
+const path = require('path');
+
+function createTempPackage(
+  packageJson: {...},
+  packagePath: string = fs.mkdtempSync(
+    path.join(os.tmpdir(), 'rn-metro-config-test-'),
+  ),
+) {
+  fs.mkdirSync(packagePath, {recursive: true});
   if (typeof packageJson === 'object') {
-    fs.writeFileSync(path.join(packagePath, 'package.json'), JSON.stringify(packageJson), 'utf8');
+    fs.writeFileSync(
+      path.join(packagePath, 'package.json'),
+      JSON.stringify(packageJson),
+      'utf8',
+    );
   }
   return packagePath;
 }
@@ -24,9 +44,12 @@ describe('getWorkspaceRoot', () => {
       name: 'package-root',
       workspaces: ['packages/my-app', 'packages/my-lib'],
     });
-    const tempPackagePath = createTempPackage({
-      name: 'my-app',
-    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    const tempPackagePath = createTempPackage(
+      {
+        name: 'my-app',
+      },
+      path.join(tempWorkspaceRootPath, 'packages', 'my-app'),
+    );
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
@@ -35,9 +58,12 @@ describe('getWorkspaceRoot', () => {
       name: 'package-root',
       workspaces: ['packages/*'],
     });
-    const tempPackagePath = createTempPackage({
-      name: 'my-app',
-    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    const tempPackagePath = createTempPackage(
+      {
+        name: 'my-app',
+      },
+      path.join(tempWorkspaceRootPath, 'packages', 'my-app'),
+    );
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
@@ -48,9 +74,12 @@ describe('getWorkspaceRoot', () => {
         packages: ['packages/*'],
       },
     });
-    const tempPackagePath = createTempPackage({
-      name: 'my-app',
-    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    const tempPackagePath = createTempPackage(
+      {
+        name: 'my-app',
+      },
+      path.join(tempWorkspaceRootPath, 'packages', 'my-app'),
+    );
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
@@ -60,10 +89,17 @@ describe('getWorkspaceRoot', () => {
     });
     // Create the pnpm workspace configuration (see https://pnpm.io/pnpm-workspace_yaml)
     const workspacesConfig = 'packages: ["packages/*"]';
-    fs.writeFileSync(path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'), workspacesConfig, 'utf8');
-    const tempPackagePath = createTempPackage({
-      name: 'my-app',
-    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    fs.writeFileSync(
+      path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'),
+      workspacesConfig,
+      'utf8',
+    );
+    const tempPackagePath = createTempPackage(
+      {
+        name: 'my-app',
+      },
+      path.join(tempWorkspaceRootPath, 'packages', 'my-app'),
+    );
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
@@ -73,11 +109,17 @@ describe('getWorkspaceRoot', () => {
     });
     // Create the pnpm workspace configuration (see https://pnpm.io/pnpm-workspace_yaml)
     const workspacesConfig = 'packages: ["packages/*", "!packages/*-app"]';
-    fs.writeFileSync(path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'), workspacesConfig, 'utf8');
-    const tempPackagePath = createTempPackage({
-      name: 'my-app',
-    }, path.join(tempWorkspaceRootPath, 'packages', 'my-app'));
+    fs.writeFileSync(
+      path.join(tempWorkspaceRootPath, 'pnpm-workspace.yaml'),
+      workspacesConfig,
+      'utf8',
+    );
+    const tempPackagePath = createTempPackage(
+      {
+        name: 'my-app',
+      },
+      path.join(tempWorkspaceRootPath, 'packages', 'my-app'),
+    );
     expect(getWorkspaceRoot(tempPackagePath)).toBe(null);
   });
 });
-

From 257a412bea44c3f52f95139bad9722d7f075644c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Tue, 2 Jan 2024 16:01:56 +0100
Subject: [PATCH 15/20] Apply more suggestions from code review

---
 .../utils/__tests__/getWorkspaceRoot-test.js  | 14 ++---
 .../src/utils/getWorkspaceRoot.js             | 56 ++++++++++---------
 2 files changed, 36 insertions(+), 34 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index 1eb20cf7ceda01..dd25247bc10823 100644
--- a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -9,10 +9,10 @@
  * @oncall react_native
  */
 
-const {getWorkspaceRoot} = require('../getWorkspaceRoot');
-const fs = require('fs');
-const os = require('os');
-const path = require('path');
+import {getWorkspaceRoot} from '../getWorkspaceRoot';
+import fs from 'fs';
+import os from 'os';
+import path from 'path';
 
 function createTempPackage(
   packageJson: {...},
@@ -39,7 +39,7 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(null);
   });
 
-  test('supports an NPM workspace', () => {
+  test('supports an npm workspace', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
       workspaces: ['packages/my-app', 'packages/my-lib'],
@@ -53,7 +53,7 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
-  test('supports a Yarn workspace', () => {
+  test('supports a yarn workspace', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
       workspaces: ['packages/*'],
@@ -67,7 +67,7 @@ describe('getWorkspaceRoot', () => {
     expect(getWorkspaceRoot(tempPackagePath)).toBe(tempWorkspaceRootPath);
   });
 
-  test('supports a Yarn workspace (object style)', () => {
+  test('supports a yarn workspace (object style)', () => {
     const tempWorkspaceRootPath = createTempPackage({
       name: 'package-root',
       workspaces: {
diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index 86c951312ae13c..43153ba9ccd2f9 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -9,55 +9,57 @@
  * @oncall react_native
  */
 
-const fs = require('fs');
-const micromatch = require('micromatch');
-const path = require('path');
-const yaml = require('yaml');
+import {logger} from '@react-native-community/cli-tools';
+import fs from 'fs';
+import micromatch from 'micromatch';
+import path from 'path';
+import yaml from 'yaml';
 
 /**
  * Get the workspace paths from the path of a potential workspace root.
  *
  * This supports:
- * - [NPM workspaces](https://docs.npmjs.com/cli/v10/using-npm/workspaces)
- * - [Yarn workspaces](https://yarnpkg.com/features/workspaces)
- * - [PNPM workspaces](https://pnpm.io/workspaces)
+ * - [npm workspaces](https://docs.npmjs.com/cli/v10/using-npm/workspaces)
+ * - [yarn workspaces](https://yarnpkg.com/features/workspaces)
+ * - [pnpm workspaces](https://pnpm.io/workspaces)
  */
 function getWorkspacePaths(packagePath: string): Array<string> {
-  const result /*: string[] */ = [];
   try {
+    // Checking pnpm workspaces first
+    const pnpmWorkspacePath = path.resolve(packagePath, 'pnpm-workspace.yaml');
+    if (fs.existsSync(pnpmWorkspacePath)) {
+      const pnpmWorkspaceConfig = yaml.parse(
+        fs.readFileSync(pnpmWorkspacePath, 'utf8'),
+      );
+      if (
+        typeof pnpmWorkspaceConfig === 'object' &&
+        Array.isArray(pnpmWorkspaceConfig.packages)
+      ) {
+        return pnpmWorkspaceConfig.packages;
+      }
+    }
+    // Falling back to npm / yarn workspaces
     const packageJsonPath = path.resolve(packagePath, 'package.json');
     const {workspaces} = JSON.parse(fs.readFileSync(packageJsonPath, 'utf8'));
     if (Array.isArray(workspaces)) {
-      result.push(...workspaces);
+      return workspaces;
     } else if (
       typeof workspaces === 'object' &&
       Array.isArray(workspaces.packages)
     ) {
-      // An alternative way for Yarn to declare workspace packages
-      result.push(...workspaces.packages);
-    }
-    // Falling back to PNPN workspaces
-    const pnpmWorkspacePath = path.resolve(packagePath, 'pnpm-workspace.yaml');
-    const pnpmWorkspaceConfig = yaml.parse(
-      fs.readFileSync(pnpmWorkspacePath, 'utf8'),
-    );
-    if (
-      typeof pnpmWorkspaceConfig === 'object' &&
-      Array.isArray(pnpmWorkspaceConfig.packages)
-    ) {
-      result.push(...pnpmWorkspaceConfig.packages);
+      // An alternative way for yarn to declare workspace packages
+      return workspaces.packages;
     }
   } catch (err) {
     if (err.code !== 'ENOENT') {
-      console.warn(`Failed getting workspace root from ${packagePath}:`, err);
+      logger.debug(`Failed getting workspace root from ${packagePath}: ${err}`);
     }
-  } finally {
-    return result;
   }
+  return [];
 }
 
 /**
- * Resolves the root of an npm or Yarn workspace, by traversing the file tree
+ * Resolves the root of an npm or yarn workspace, by traversing the file tree
  * upwards from a `candidatePath` in the search for
  * - a directory with a package.json
  * - which has a `workspaces` array of strings
@@ -69,7 +71,7 @@ export function getWorkspaceRoot(
 ) /*: ?string */ {
   const workspacePaths = getWorkspacePaths(candidatePath);
   // If one of the workspaces match the project root, this is the workspace root
-  // Note: While NPM workspaces doesn't currently support globs, Yarn does, which is why we use micromatch
+  // Note: While npm workspaces doesn't currently support globs, yarn does, which is why we use micromatch
   const relativePath = path.relative(candidatePath, projectRoot);
   // Using this instead of `micromatch.isMatch` to enable excluding patterns
   if (micromatch([relativePath], workspacePaths).length > 0) {

From 60b6a836fc64cdd484639dfdd2238b6d5722ad0c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Tue, 2 Jan 2024 16:16:14 +0100
Subject: [PATCH 16/20] Using more flow without comments

---
 packages/community-cli-plugin/src/utils/getWorkspaceRoot.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
index 43153ba9ccd2f9..3101adde23816d 100644
--- a/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
+++ b/packages/community-cli-plugin/src/utils/getWorkspaceRoot.js
@@ -66,9 +66,9 @@ function getWorkspacePaths(packagePath: string): Array<string> {
  * - which (possibly via a glob) includes the project root
  */
 export function getWorkspaceRoot(
-  projectRoot /*: string */,
-  candidatePath /*: string */ = projectRoot,
-) /*: ?string */ {
+  projectRoot: string,
+  candidatePath: string = projectRoot,
+): ?string {
   const workspacePaths = getWorkspacePaths(candidatePath);
   // If one of the workspaces match the project root, this is the workspace root
   // Note: While npm workspaces doesn't currently support globs, yarn does, which is why we use micromatch

From d63b235a7113bb3198e6a4006a902fc7acd41fd1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 1 Feb 2024 22:07:50 +0100
Subject: [PATCH 17/20] Implemented a failing test

---
 .../utils/__tests__/getWorkspaceRoot-test.js  |  19 +--
 .../utils/__tests__/loadMetroConfig-test.js   | 133 ++++++++++++++++++
 .../src/utils/__tests__/temporary-package.js  |  33 +++++
 3 files changed, 167 insertions(+), 18 deletions(-)
 create mode 100644 packages/community-cli-plugin/src/utils/__tests__/loadMetroConfig-test.js
 create mode 100644 packages/community-cli-plugin/src/utils/__tests__/temporary-package.js

diff --git a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
index dd25247bc10823..6d73456d9b2c4a 100644
--- a/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
+++ b/packages/community-cli-plugin/src/utils/__tests__/getWorkspaceRoot-test.js
@@ -10,27 +10,10 @@
  */
 
 import {getWorkspaceRoot} from '../getWorkspaceRoot';
+import {createTempPackage} from './temporary-package';
 import fs from 'fs';
-import os from 'os';
 import path from 'path';
 
-function createTempPackage(
-  packageJson: {...},
-  packagePath: string = fs.mkdtempSync(
-    path.join(os.tmpdir(), 'rn-metro-config-test-'),
-  ),
-) {
-  fs.mkdirSync(packagePath, {recursive: true});
-  if (typeof packageJson === 'object') {
-    fs.writeFileSync(
-      path.join(packagePath, 'package.json'),
-      JSON.stringify(packageJson),
-      'utf8',
-    );
-  }
-  return packagePath;
-}
-
 describe('getWorkspaceRoot', () => {
   test('returns null if not in a workspace', () => {
     const tempPackagePath = createTempPackage({
diff --git a/packages/community-cli-plugin/src/utils/__tests__/loadMetroConfig-test.js b/packages/community-cli-plugin/src/utils/__tests__/loadMetroConfig-test.js
new file mode 100644
index 00000000000000..4610e874cb5192
--- /dev/null
+++ b/packages/community-cli-plugin/src/utils/__tests__/loadMetroConfig-test.js
@@ -0,0 +1,133 @@
+/**
+ * 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
+ */
+
+import loadMetroConfig from '../loadMetroConfig';
+import {createTempPackage} from './temporary-package';
+import fs from 'fs';
+import path from 'path';
+
+/**
+ * Resolves a package by its name and creates a symbolic link in a node_modules directory
+ */
+function createPackageLink(nodeModulesPath: string, packageName: string) {
+  // Resolve the packages path on disk
+  const destinationPath = path.dirname(require.resolve(packageName));
+  const packageScope = packageName.includes('/')
+    ? packageName.split('/')[0]
+    : undefined;
+
+  // Create a parent directory for a @scoped package
+  if (typeof packageScope === 'string') {
+    fs.mkdirSync(path.join(nodeModulesPath, packageScope));
+  }
+
+  const sourcePath = path.join(nodeModulesPath, packageName);
+  fs.symlinkSync(destinationPath, sourcePath);
+}
+
+function createTempConfig(projectRoot: string, metroConfig: {...}) {
+  const content = `
+    const {getDefaultConfig, mergeConfig} = require('@react-native/metro-config');
+    const config = ${JSON.stringify(metroConfig)};
+    module.exports = mergeConfig(getDefaultConfig(__dirname), config);
+  `;
+  const configPath = path.join(projectRoot, 'metro.config.js');
+  fs.writeFileSync(configPath, content, 'utf8');
+
+  const nodeModulesPath = path.join(projectRoot, 'node_modules');
+  fs.mkdirSync(nodeModulesPath);
+  // Create a symbolic link to the '@react-native/metro-config' package used by the config
+  createPackageLink(nodeModulesPath, '@react-native/metro-config');
+}
+
+const configLoadingContext = {
+  reactNativePath: path.dirname(require.resolve('react-native/package.json')),
+  platforms: {
+    ios: {npmPackageName: 'temp-package'},
+    android: {npmPackageName: 'temp-package'},
+  },
+};
+
+describe('loadMetroConfig', () => {
+  test('loads an empty config', async () => {
+    const rootPath = createTempPackage({name: 'temp-app'});
+    createTempConfig(rootPath, {});
+
+    const loadedConfig = await loadMetroConfig({
+      root: rootPath,
+      ...configLoadingContext,
+    });
+    expect(loadedConfig.projectRoot).toEqual(rootPath);
+    expect(loadedConfig.watchFolders).toEqual([rootPath]);
+  });
+
+  test('loads watch folders', async () => {
+    const rootPath = createTempPackage({
+      name: 'temp-app',
+    });
+    createTempConfig(rootPath, {
+      watchFolders: ['somewhere-else'],
+    });
+
+    const loadedConfig = await loadMetroConfig({
+      root: rootPath,
+      ...configLoadingContext,
+    });
+    expect(loadedConfig.projectRoot).toEqual(rootPath);
+    expect(loadedConfig.watchFolders).toEqual([rootPath, 'somewhere-else']);
+  });
+
+  test('includes an npm workspace root if no watchFolders are defined', async () => {
+    const rootPath = createTempPackage({
+      name: 'temp-root',
+      workspaces: ['packages/temp-app'],
+    });
+    // Create a config inside a sub-package
+    const projectRoot = createTempPackage(
+      {
+        name: 'temp-app',
+      },
+      path.join(rootPath, 'packages', 'temp-app'),
+    );
+    createTempConfig(projectRoot, {});
+
+    const loadedConfig = await loadMetroConfig({
+      root: projectRoot,
+      ...configLoadingContext,
+    });
+    expect(loadedConfig.projectRoot).toEqual(projectRoot);
+    expect(loadedConfig.watchFolders).toEqual([projectRoot, rootPath]);
+  });
+
+  test('does not resolve an npm workspace root if watchFolders are defined', async () => {
+    const rootPath = createTempPackage({
+      name: 'temp-root',
+      workspaces: ['packages/temp-app'],
+    });
+    // Create a config inside a sub-package
+    const projectRoot = createTempPackage(
+      {
+        name: 'temp-app',
+      },
+      path.join(rootPath, 'packages', 'temp-app'),
+    );
+    createTempConfig(projectRoot, {
+      watchFolders: [],
+    });
+
+    const loadedConfig = await loadMetroConfig({
+      root: projectRoot,
+      ...configLoadingContext,
+    });
+    expect(loadedConfig.projectRoot).toEqual(projectRoot);
+    expect(loadedConfig.watchFolders).toEqual([projectRoot]);
+  });
+});
diff --git a/packages/community-cli-plugin/src/utils/__tests__/temporary-package.js b/packages/community-cli-plugin/src/utils/__tests__/temporary-package.js
new file mode 100644
index 00000000000000..6f2ebf69c88446
--- /dev/null
+++ b/packages/community-cli-plugin/src/utils/__tests__/temporary-package.js
@@ -0,0 +1,33 @@
+/**
+ * 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
+ */
+
+import fs from 'fs';
+import os from 'os';
+import path from 'path';
+
+export function createTempPackage(
+  packageJson: {...},
+  packagePath: string = fs.mkdtempSync(
+    path.join(os.tmpdir(), 'rn-metro-config-test-'),
+  ),
+): string {
+  fs.mkdirSync(packagePath, {recursive: true});
+  if (typeof packageJson === 'object') {
+    fs.writeFileSync(
+      path.join(packagePath, 'package.json'),
+      JSON.stringify(packageJson),
+      'utf8',
+    );
+  }
+
+  // Wrapping path in realpath to resolve any symlinks introduced by mkdtemp
+  return fs.realpathSync(packagePath);
+}

From 55fb330d3d6f69f9c49af90e1ec5dde9593e6b56 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 1 Feb 2024 23:34:00 +0100
Subject: [PATCH 18/20] Updated @react-native/metro-config return MetroConfig
 instead of ConfigT and remove default watchFolders

---
 packages/metro-config/index.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/packages/metro-config/index.js b/packages/metro-config/index.js
index 2abf2c8757d475..6ae5fd7c8c72df 100644
--- a/packages/metro-config/index.js
+++ b/packages/metro-config/index.js
@@ -8,7 +8,7 @@
  * @noformat
  */
 
-/*:: import type {ConfigT} from 'metro-config'; */
+/*:: import type {InputConfigT} from 'metro-config'; */
 
 const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
 
@@ -41,7 +41,7 @@ const INTERNAL_CALLSITES_REGEX = new RegExp(
  */
 function getDefaultConfig(
   projectRoot /*: string */
-) /*: ConfigT */ {
+) /*: InputConfigT */ {
   const config = {
     resolver: {
       resolverMainFields: ['react-native', 'browser', 'main'],
@@ -82,14 +82,17 @@ function getDefaultConfig(
         },
       }),
     },
-    watchFolders: [],
   };
 
   // Set global hook so that the CLI can detect when this config has been loaded
   global.__REACT_NATIVE_METRO_CONFIG_LOADED = true;
 
+  const defaults /* :InputConfigT */ = {...getBaseConfig.getDefaultValues(projectRoot)};
+  // Deleting default empty watchFolders array allow a developer to explicitly specify it
+  delete defaults.watchFolders;
+
   return mergeConfig(
-    getBaseConfig.getDefaultValues(projectRoot),
+    defaults,
     config,
   );
 }

From ab7816e761a9b7e4fba12f538fc2363c868e38e6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 1 Feb 2024 23:34:50 +0100
Subject: [PATCH 19/20] Provide a default "undefined" override for watchFolders

---
 .../src/utils/loadMetroConfig.js                   | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/loadMetroConfig.js b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
index b233b873252c62..ed8e4ca33348fd 100644
--- a/packages/community-cli-plugin/src/utils/loadMetroConfig.js
+++ b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
@@ -119,10 +119,16 @@ This warning will be removed in future (https://github.com/facebook/metro/issues
     }
   }
 
-  const config = await loadConfig({
-    cwd,
-    ...options,
-  });
+  const config = await loadConfig(
+    {
+      cwd,
+      ...options,
+    },
+    {
+      // Enables users to explicitly specify watchFolders
+      watchFolders: undefined,
+    },
+  );
 
   const overrideConfig = getOverrideConfig(ctx, config);
 

From 7fd9661b53972561cbf28311b5e3fe213756521b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kr=C3=A6n=20Hansen?= <kraen.hansen@mongodb.com>
Date: Thu, 1 Feb 2024 23:37:08 +0100
Subject: [PATCH 20/20] Infer workspace root only if watchFolders are not
 explicitly specified

---
 .../src/utils/loadMetroConfig.js              | 23 +++++++++++--------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/packages/community-cli-plugin/src/utils/loadMetroConfig.js b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
index ed8e4ca33348fd..8c471a1e0de7ff 100644
--- a/packages/community-cli-plugin/src/utils/loadMetroConfig.js
+++ b/packages/community-cli-plugin/src/utils/loadMetroConfig.js
@@ -54,6 +54,19 @@ function getOverrideConfig(
     );
   }
 
+  // Always include the project root as a watch folder, since Metro expects this
+  const watchFolders = [config.projectRoot];
+
+  if (typeof config.watchFolders !== 'undefined') {
+    watchFolders.push(...config.watchFolders);
+  } else {
+    // Fallback to inferring a workspace root
+    const workspaceRoot = getWorkspaceRoot(ctx.root);
+    if (typeof workspaceRoot === 'string') {
+      watchFolders.push(workspaceRoot);
+    }
+  }
+
   const overrides: InputConfigT = {
     resolver,
     serializer: {
@@ -71,17 +84,9 @@ function getOverrideConfig(
         ),
       ],
     },
+    watchFolders,
   };
 
-  // Applying the heuristic of appending workspace root as watch folder,
-  // only if no other watch folder (beside the project root) has been given.
-  if (!config.watchFolders.some(folder => folder !== ctx.root)) {
-    const workspaceRoot = getWorkspaceRoot(ctx.root);
-    if (typeof workspaceRoot === 'string') {
-      overrides.watchFolders = [...config.watchFolders, workspaceRoot];
-    }
-  }
-
   return overrides;
 }