[doctor] check for sdkVersion in Expo config (#4732)

* [doctor] check for expo.sdkVersion

* use @expo/config SDK installed version resolution to compare with Expo config

* remove bad mock stuff

packages/expo-doctor/__mocks__/resolve-from.ts

@@ -0,0 +1,20 @@
+module.exports = require(require.resolve('resolve-from'));
+
+module.exports.silent = (fromDirectory, request) => {
+  const fs = require('fs');
+  const path = require('path');
+  try {
+    fromDirectory = fs.realpathSync(fromDirectory);
+  } catch (error) {
+    if (error.code === 'ENOENT') {
+      fromDirectory = path.resolve(fromDirectory);
+    } else {
+      return;
+    }
+  }
+
+  const outputPath = path.join(fromDirectory, 'node_modules', request);
+  if (fs.existsSync(outputPath)) {
+    return outputPath;
+  }
+};

packages/expo-doctor/package.json

@@ -41,6 +41,7 @@
     "@expo/spawn-async": "^1.7.0",
     "chalk": "^4.0.0",
     "ora": "3.4.0",
+    "resolve-from": "^5.0.0",
     "semver": "7.3.2"
   }
 }

packages/expo-doctor/src/checks/ExpoConfigCommonIssueCheck.ts

@@ -0,0 +1,55 @@
+import JsonFile from '@expo/json-file';
+import resolveFrom from 'resolve-from';
+
+import { DoctorCheck, DoctorCheckParams, DoctorCheckResult } from './checks.types';
+
+export class ExpoConfigCommonIssueCheck implements DoctorCheck {
+  description = 'Check Expo config for common issues';
+
+  sdkVersionRange = '*';
+
+  async runAsync({ projectRoot, exp }: DoctorCheckParams): Promise<DoctorCheckResult> {
+    const issues: string[] = [];
+    let advice;
+
+    // compare SDK version in package.json with installed expo package version
+    // If these don't match, it almost certainly means the user specified expo.sdkVersion in their app.json/ app.config.js
+    const expoSDKVersionFromPackageJson = getExpoSDKVersionFromPackage(projectRoot);
+
+    if (expoSDKVersionFromPackageJson !== exp.sdkVersion) {
+      issues.push(
+        "It appears that expo.sdkVersion is defined in your app.json/ app.config.js. This can cause 'expo install' to install dependency versions for the wrong SDK. SDK version is determined by the version of the expo package installed in your project."
+      );
+      advice = 'Remove expo.sdkVersion from your app.json/ app.config.js.';
+    }
+
+    return {
+      isSuccessful: issues.length === 0,
+      issues,
+      advice,
+    };
+  }
+}
+
+/**
+ * Resolve the Expo SDK Version either from the input Expo config or from the installed
+ * version of the `expo` package.
+ * Adapted from https://github.com/expo/expo/blob/main/packages/%40expo/config/src/getExpoSDKVersion.ts
+ */
+function getExpoSDKVersionFromPackage(projectRoot: string): string | undefined {
+  const packageJsonPath = resolveFrom.silent(projectRoot, 'expo/package.json');
+  if (!packageJsonPath) {
+    // (probably) technically impossible - if this happens, `getConfig` throws and Doctor crashes
+    return undefined;
+  }
+  const expoPackageJson = JsonFile.read(packageJsonPath, { json5: true });
+  const { version: packageVersion } = expoPackageJson;
+
+  if (!(typeof packageVersion === 'string')) {
+    // This is technically impossible.
+    return undefined;
+  }
+
+  const majorVersion = packageVersion.split('.').shift();
+  return `${majorVersion}.0.0`;
+}

packages/expo-doctor/src/checks/ExpoConfigSchemaCheck.ts

@@ -5,7 +5,7 @@ import { validateWithSchemaAsync } from '../utils/schema';
 import { DoctorCheck, DoctorCheckParams, DoctorCheckResult } from './checks.types';
 
 export class ExpoConfigSchemaCheck implements DoctorCheck {
-  description = 'Check Expo config (app.json/ app.config.js)';
+  description = 'Check Expo config (app.json/ app.config.js) schema';
 
   sdkVersionRange = '*';
 

packages/expo-doctor/src/checks/__tests__/ExpoConfigCommonIssueCheck.test.ts

@@ -0,0 +1,55 @@
+import { vol } from 'memfs';
+
+import { ExpoConfigCommonIssueCheck } from '../ExpoConfigCommonIssueCheck';
+
+jest.mock('resolve-from');
+jest.mock('fs');
+
+const projectRoot = '/tmp/project';
+
+// required by runAsync
+const additionalProjectProps = {
+  exp: {
+    name: 'name',
+    slug: 'slug',
+    sdkVersion: '49.0.0',
+  },
+  projectRoot,
+};
+
+describe('runAsync', () => {
+  it('returns result with isSuccessful = true if Expo config SDK version matches installed version', async () => {
+    vol.fromJSON({
+      [projectRoot + '/node_modules/expo/package.json']: `{
+        "version": "49.0.0"
+      }`,
+    });
+
+    const check = new ExpoConfigCommonIssueCheck();
+    const result = await check.runAsync({
+      pkg: { name: 'name', version: '1.0.0' },
+      ...additionalProjectProps,
+    });
+    expect(result.isSuccessful).toBeTruthy();
+  });
+
+  it('returns result with isSuccessful = false if Expo config SDK version does not match installed version', async () => {
+    vol.fromJSON({
+      [projectRoot + '/node_modules/expo/package.json']: `{
+        "version": "48.0.0"
+      }`,
+    });
+
+    const check = new ExpoConfigCommonIssueCheck();
+    const result = await check.runAsync({
+      pkg: { name: 'name', version: '1.0.0' },
+      ...additionalProjectProps,
+      exp: {
+        name: 'name',
+        sdkVersion: '49.0.0',
+        slug: 'slug',
+      },
+    });
+    expect(result.isSuccessful).toBeFalsy();
+  });
+});

packages/expo-doctor/src/doctor.ts

@@ -2,6 +2,7 @@ import { getConfig } from '@expo/config';
 import chalk from 'chalk';
 import semver from 'semver';
 
+import { ExpoConfigCommonIssueCheck } from './checks/ExpoConfigCommonIssueCheck';
 import { DirectPackageInstallCheck } from './checks/DirectPackageInstallCheck';
 import { ExpoConfigSchemaCheck } from './checks/ExpoConfigSchemaCheck';
 import { GlobalPackageInstalledCheck } from './checks/GlobalPackageInstalledCheck';
@@ -140,6 +141,7 @@ export async function actionAsync(projectRoot: string) {
     new SupportPackageVersionCheck(),
     new InstalledDependencyVersionCheck(),
     new ExpoConfigSchemaCheck(),
+    new ExpoConfigCommonIssueCheck(),
     new DirectPackageInstallCheck(),
     new PackageJsonCheck(),
     new ProjectSetupCheck(),