fix(migrations): improve error handling for loading migrations (#52)

.gitignore

@@ -5,4 +5,4 @@ typedoc/
 .vscode/
 coverage/
 .nyc_output/
-migrations/
+./migrations/

package.json

@@ -36,6 +36,8 @@
  "yargs": "^5.0.0"
  },
  "devDependencies": {
+ "chai": "^4.1.2",
+ "chai-as-promised": "^7.1.1",
  "cz-conventional-changelog": "^2.0.0",
  "del": "^2.2.2",
  "husky": "^0.14.3",

src/migration.ts

@@ -7,6 +7,12 @@ import * as fs from 'mz/fs';
 
 export type TaskType = 'up' | 'down';
 
+export class MigrationLoadError extends Error {
+ constructor(public migration: Migration, public migrationDir: string, public error: any) {
+ super('Error loading migration file ' + migrationDir + sep + chalk.bold(migration.name) + '.js:\n' + error);
+ }
+}
+
 export class FirstDownMigrationError extends Error {
  constructor(public migration: Migration) {
  super(`The first migration cannot be a down migration (${migration.name})`);
@@ -137,11 +143,11 @@ export class Task {
  migrationDir = config.migrationOutDir;
  }
  }
+ const path = await this.migration.getPath(migrationDir);
  try {
- const path = await this.migration.getPath(migrationDir);
  migrationExports = require(path);
  } catch (err) {
- throw new MigrationNotFoundError(this.migration, migrationDir);
+ throw new MigrationLoadError(this.migration, migrationDir, err);
  }
  if (typeof migrationExports[this.type] !== 'function') {
  throw new TaskTypeNotFoundError(this.migration, this.type, migrationDir);

src/test/migration.test.ts

@@ -1,9 +1,13 @@
-import * as assert from 'assert';
+import * as chai from 'chai';
+const chaiAsPromised = require('chai-as-promised');
+chai.use(chaiAsPromised);
+const assert = chai.assert;
 import * as fs from 'mz/fs';
 import * as path from 'path';
 import * as pg from 'pg';
 import {
  Migration,
+ MigrationLoadError,
  MigrationNotFoundError,
  MigrationExecutionError,
  TaskTypeNotFoundError,
@@ -129,61 +133,31 @@ describe('migration', () => {
  const task = new Task({type: 'up', migration: new Migration({name: 'not_found'})});
  const head = new Commit({sha1: 'HEADCOMMITSHA1'});
  const trigger = new Commit({sha1: 'TRIGGERCOMMITSHA1'});
- try {
- await task.execute(__dirname + '/migrations', adapter, head, trigger);
- throw new assert.AssertionError({
- message: 'No MigrationNotFoundError was thrown.'
- });
- } catch (err) {
- if (!(err instanceof MigrationNotFoundError)) {
- throw err;
- }
- }
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), MigrationNotFoundError);
+ });
+ it('should throw a MigrationLoadError if the migration fails loading', async () => {
+ const task = new Task({type: 'up', migration: new Migration({name: 'error_load'})});
+ const head = new Commit({sha1: 'HEADCOMMITSHA1'});
+ const trigger = new Commit({sha1: 'TRIGGERCOMMITSHA1'});
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), MigrationLoadError);
  });
  it('should throw a TaskTypeNotFoundError if the migration has no up or down function', async () => {
  const task = new Task({type: 'up', migration: new Migration({name: 'no_up'})});
  const head = new Commit({sha1: 'HEADCOMMITSHA1'});
  const trigger = new Commit({sha1: 'TRIGGERCOMMITSHA1'});
- try {
- await task.execute(__dirname + '/migrations', adapter, head, trigger);
- throw new assert.AssertionError({
- message: 'No TaskTypeNotFoundError was thrown.'
- });
- } catch (err) {
- if (!(err instanceof TaskTypeNotFoundError)) {
- throw err;
- }
- }
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), TaskTypeNotFoundError);
  });
  it('should throw a MigrationExecutionError when the migration returns a rejected promise', async () => {
  const task = new Task({type: 'up', migration: new Migration({name: 'error_async'})});
  const head = new Commit({sha1: 'HEADCOMMITSHA1'});
  const trigger = new Commit({sha1: 'TRIGGERCOMMITSHA1'});
- try {
- await task.execute(__dirname + '/migrations', adapter, head, trigger);
- throw new assert.AssertionError({
- message: 'No MigrationExecutionError was thrown.'
- });
- } catch (err) {
- if (!(err instanceof MigrationExecutionError)) {
- throw err;
- }
- }
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), MigrationExecutionError);
  });
  it('should throw a MigrationExecutionError when the migration throws sync', async () => {
  const task = new Task({type: 'up', migration: new Migration({name: 'error_sync'})});
  const head = new Commit({sha1: 'HEADCOMMITSHA1'});
  const trigger = new Commit({sha1: 'TRIGGERCOMMITSHA1'});
- try {
- await task.execute(__dirname + '/migrations', adapter, head, trigger);
- throw new assert.AssertionError({
- message: 'No Migration ExecutionError was thrown.'
- });
- } catch (err) {
- if (!(err instanceof MigrationExecutionError)) {
- throw err;
- }
- }
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), MigrationExecutionError);
  });
  it('should throw a MigrationExecutionError when the migration would crash the process', async () => {
  const task = new Task({type: 'up', migration: new Migration({name: 'error_crash'})});
@@ -193,14 +167,7 @@ describe('migration', () => {
  try {
  listener = process.listeners('uncaughtException').pop();
  process.removeListener('uncaughtException', listener);
- await task.execute(__dirname + '/migrations', adapter, head, trigger);
- throw new assert.AssertionError({
- message: 'No Migration ExecutionError was thrown.'
- });
- } catch (err) {
- if (!(err instanceof MigrationExecutionError)) {
- throw err;
- }
+ await assert.isRejected(task.execute(__dirname + '/migrations', adapter, head, trigger), MigrationExecutionError);
  } finally {
  process.addListener('uncaughtException', listener);
  }
@@ -209,16 +176,7 @@ describe('migration', () => {
  describe('toString', () => {
  it('should throw if the task type is unknown', async () => {
  const task = new Task(<any>{type: 'd'});
- try {
- task.toString();
- throw new assert.AssertionError({
- message: 'Task did not throw error on toString with wrong type'
- });
- } catch (err) {
- if (!(err instanceof UnknownTaskTypeError)) {
- throw err;
- }
- }
+ assert.throws(() => task.toString(), UnknownTaskTypeError);
  });
  });
  });

src/test/migrations/error_load.ts

@@ -0,0 +1,2 @@
+
+throw new Error('Migration failed loading');

typings.json

@@ -17,5 +17,9 @@
  },
  "globalDevDependencies": {
  "mocha": "registry:env/mocha#2.2.5+20160926180742"
+ },
+ "devDependencies": {
+ "chai": "registry:npm/chai#3.5.0+20160723033700",
+ "chai-as-promised": "registry:npm/chai-as-promised#5.1.0+20160310030142"
  }
 }