style(README): add note about what package.json is used

- add an additional note about what package.json is used by default
- add example on how to change the package.json used

Author: hasezoey

README.md

@@ -25,33 +25,34 @@ Works perfectly [with Travis CI](https://github.com/nodkz/graphql-compose-mongoo
 <!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
 **Table of Contents**  *generated with [DocToc](https://github.com/thlorenz/doctoc)*
 
-- [Installation](#installation)
-  - [Requirements](#requirements)
-    - [Known Incompatibilities](#known-incompatibilities)
-  - [mongodb-memory-server](#mongodb-memory-server)
-  - [mongodb-memory-server-global](#mongodb-memory-server-global)
-  - [mongodb-memory-server-core](#mongodb-memory-server-core)
-  - [Configuring which mongod binary to use](#configuring-which-mongod-binary-to-use)
-- [Usage](#usage)
-  - [Simple server start](#simple-server-start)
-  - [Available options for MongoMemoryServer](#available-options-for-mongomemoryserver)
-  - [Replica Set start](#replica-set-start)
-  - [Available options for MongoMemoryReplSet](#available-options-for-mongomemoryreplset)
-  - [Options which can be set via ENVIRONMENT variables](#options-which-can-be-set-via-environment-variables)
-  - [Options which can be set via package.json's `config` section](#options-which-can-be-set-via-packagejsons-config-section)
-  - [Simple test with MongoClient](#simple-test-with-mongoclient)
-  - [Provide connection string to mongoose](#provide-connection-string-to-mongoose)
-  - [Several mongoose connections simultaneously](#several-mongoose-connections-simultaneously)
-  - [Simple Mocha/Chai test example](#simple-mochachai-test-example)
-  - [Simple Jest test example](#simple-jest-test-example)
-  - [AVA test runner](#ava-test-runner)
-  - [Docker Alpine](#docker-alpine)
-  - [Enable Debug Mode](#enable-debug-mode)
-- [CI](#ci)
-- [Contributing](#contributing)
-- [Credits](#credits)
-- [License](#license)
-- [Maintainers](#maintainers)
+- [MongoDB In-Memory Server](#mongodb-in-memory-server)
+  - [Installation](#installation)
+    - [Requirements](#requirements)
+      - [Known Incompatibilities](#known-incompatibilities)
+    - [mongodb-memory-server](#mongodb-memory-server)
+    - [mongodb-memory-server-global](#mongodb-memory-server-global)
+    - [mongodb-memory-server-core](#mongodb-memory-server-core)
+    - [Configuring which mongod binary to use](#configuring-which-mongod-binary-to-use)
+  - [Usage](#usage)
+    - [Simple server start](#simple-server-start)
+    - [Available options for MongoMemoryServer](#available-options-for-mongomemoryserver)
+    - [Replica Set start](#replica-set-start)
+    - [Available options for MongoMemoryReplSet](#available-options-for-mongomemoryreplset)
+    - [Options which can be set via ENVIRONMENT variables](#options-which-can-be-set-via-environment-variables)
+    - [Options which can be set via package.json's `config` section](#options-which-can-be-set-via-packagejsons-config-section)
+    - [Simple test with MongoClient](#simple-test-with-mongoclient)
+    - [Provide connection string to mongoose](#provide-connection-string-to-mongoose)
+    - [Several mongoose connections simultaneously](#several-mongoose-connections-simultaneously)
+    - [Simple Mocha/Chai test example](#simple-mochachai-test-example)
+    - [Simple Jest test example](#simple-jest-test-example)
+    - [AVA test runner](#ava-test-runner)
+    - [Docker Alpine](#docker-alpine)
+    - [Enable Debug Mode](#enable-debug-mode)
+  - [CI](#ci)
+  - [Contributing](#contributing)
+  - [Credits](#credits)
+  - [License](#license)
+  - [Maintainers](#maintainers)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 
@@ -294,6 +295,19 @@ Environment variables have higher priority than contents of package.json.
 }
 ```
 
+By default it uses the nearest (upwards) `package.json` to `process.cwd()`.
+To change this:
+
+```ts
+import { findPackageJson } from "mongodb-memory-server-core/lib/util/resolve-config";
+
+findPackageJson('/custom/path');
+
+// OR
+
+process.chdir('/custom/path'); // not recommended
+```
+
 ### Simple test with MongoClient
 
 Take a look at this [test file](https://github.com/nodkz/mongodb-memory-server/blob/master/packages/mongodb-memory-server-core/src/__tests__/singleDB-test.ts).