From c72ca190bffacfb5302ae5f2bc53f1f1891fc294 Mon Sep 17 00:00:00 2001
From: Cedric van Putten <github@cedric.dev>
Date: Tue, 12 Mar 2024 21:20:09 +0100
Subject: [PATCH] feature: add error handling when stats file is outdated

---
 src/cli/bin.ts                  | 19 +++++++++++++++--
 src/cli/resolveOptions.ts       |  6 +-----
 src/metro/serializeStatsFile.ts |  5 +++--
 src/utils/errors.ts             | 38 +++++++++++++++++++++++++++++++++
 4 files changed, 59 insertions(+), 9 deletions(-)
 create mode 100644 src/utils/errors.ts

diff --git a/src/cli/bin.ts b/src/cli/bin.ts
index 7503786..cad2a71 100644
--- a/src/cli/bin.ts
+++ b/src/cli/bin.ts
@@ -1,6 +1,7 @@
 #!/usr/bin/env node
 import arg from 'arg';
 import open from 'open';
+import path from 'path';
 
 import { resolveOptions } from './resolveOptions';
 import { createServer } from './server';
@@ -39,8 +40,6 @@ if (args['--help']) {
 process.on('SIGINT', () => process.exit(0));
 process.on('SIGTERM', () => process.exit(0));
 
-run();
-
 async function run() {
   const options = await resolveOptions(args);
   const server = createServer(options);
@@ -54,3 +53,19 @@ async function run() {
     open(href);
   });
 }
+
+run().catch((error) => {
+  if (error.type !== 'AtlasError') {
+    throw error;
+  }
+
+  if (error.code === 'STATS_FILE_INCOMPATIBLE') {
+    const statsFile = path.relative(process.cwd(), error.statsFile);
+    console.error('Stats file is incompatible with this version, use this instead:');
+    console.error(`  npx expo-atlas@${error.incompatibleVersion} ${statsFile}`);
+  } else {
+    console.error(`${error.message} (${error.code})`);
+  }
+
+  process.exit(1);
+});
diff --git a/src/cli/resolveOptions.ts b/src/cli/resolveOptions.ts
index 8fb8a8b..2d09c0f 100644
--- a/src/cli/resolveOptions.ts
+++ b/src/cli/resolveOptions.ts
@@ -20,11 +20,7 @@ async function resolveStatsFile(input: Input) {
     throw new Error(`Could not find stats file "${statsFile}".`);
   }
 
-  try {
-    await validateStatsFile(statsFile);
-  } catch (error) {
-    throw new Error(`Stats file is incompatible with this version.`, { cause: error });
-  }
+  await validateStatsFile(statsFile);
 
   return path.resolve(statsFile);
 }
diff --git a/src/metro/serializeStatsFile.ts b/src/metro/serializeStatsFile.ts
index d20d155..6075c50 100644
--- a/src/metro/serializeStatsFile.ts
+++ b/src/metro/serializeStatsFile.ts
@@ -4,6 +4,7 @@ import path from 'path';
 import { type MetroStatsEntry } from './convertGraphToStats';
 import { name, version } from '../../package.json';
 import { env } from '../utils/env';
+import { AtlasValidationError } from '../utils/errors';
 import { mapLines, readFirstLine, readLine } from '../utils/file';
 
 export type StatsMetadata = { name: string; version: string };
@@ -21,7 +22,7 @@ export function getStatsMetdata(): StatsMetadata {
 /** Validate if the stats file is compatible with this library version */
 export async function validateStatsFile(statsFile: string, metadata = getStatsMetdata()) {
   if (!fs.existsSync(statsFile)) {
-    throw new Error(`Stats file "${statsFile}" not found.`);
+    throw new AtlasValidationError('STATS_FILE_NOT_FOUND', statsFile);
   }
 
   if (env.EXPO_NO_STATS_VALIDATION) {
@@ -32,7 +33,7 @@ export async function validateStatsFile(statsFile: string, metadata = getStatsMe
   const data = line ? JSON.parse(line) : {};
 
   if (data.name !== metadata.name || data.version !== metadata.version) {
-    throw new Error(`Stats file "${statsFile}" is incompatible with this version of the plugin.`);
+    throw new AtlasValidationError('STATS_FILE_INCOMPATIBLE', statsFile, data.version);
   }
 }
 
diff --git a/src/utils/errors.ts b/src/utils/errors.ts
new file mode 100644
index 0000000..2c9c1c0
--- /dev/null
+++ b/src/utils/errors.ts
@@ -0,0 +1,38 @@
+export class AtlasError extends Error {
+  /** A property to determine if any of the extended errors are atlas-specific errors */
+  public readonly type = 'AtlasError';
+  /** The error (class) name */
+  public readonly name: string;
+  /** The error code, specifically for these types of errors */
+  public readonly code?: string;
+
+  constructor(code: string, message = '', options?: ErrorOptions) {
+    super(message, options);
+    this.name = this.constructor.name;
+    this.code = code;
+  }
+}
+
+export class AtlasValidationError extends AtlasError {
+  constructor(
+    code: 'STATS_FILE_NOT_FOUND' | 'STATS_FILE_INCOMPATIBLE',
+    public readonly statsFile: string,
+    public readonly incompatibleVersion?: string
+  ) {
+    super(
+      code,
+      code === 'STATS_FILE_NOT_FOUND'
+        ? `Stats file not found: ${statsFile}`
+        : `Stats file is incompatible with this version.`
+    );
+  }
+}
+
+export function handleError(error: Error) {
+  if (error instanceof AtlasError) {
+    console.error(`${error.message} (${error.code})`);
+    return true;
+  }
+
+  throw error;
+}