chore: 🤖 reference example to the root directory

Author: jorgemasta

example/package.json

@@ -7,10 +7,11 @@
     "ios": "react-native run-ios",
     "start": "react-native start",
     "test": "jest",
-    "lint": "eslint ."
+    "lint": "eslint .",
+    "postinstall": "node ../scripts/examples_postinstall.js"
   },
   "dependencies": {
-    "@woonivers/react-native-document-scanner": "^2.0.0",
+    "@woonivers/react-native-document-scanner": "file:../",
     "react": "16.9.0",
     "react-native": "0.61.1",
     "react-native-permissions": "^2.0.0"

example/yarn.lock

@@ -1041,10 +1041,8 @@
     lodash.unescape "4.0.1"
     semver "5.5.0"
 
-"@woonivers/react-native-document-scanner@^1.6.2":
-  version "1.6.2"
-  resolved "https://registry.yarnpkg.com/@woonivers/react-native-document-scanner/-/react-native-document-scanner-1.6.2.tgz#67caffe0e5ca41e979c98872fd11a4e83baef315"
-  integrity sha512-+c8q0Hb5KYf3qSai33HiSPeN4qJMgutS5xoLAEkaG2BQcRgI0JvKnxQA5GnuDMehHFcIoAyCL3E1JiqhFNazSQ==
+"@woonivers/react-native-document-scanner@file:../":
+  version "0.0.0-development"
 
 abab@^2.0.0:
   version "2.0.2"

scripts/examples_postinstall.js

@@ -0,0 +1,117 @@
+#!/usr/bin/env node
+
+/*
+ * Using libraries within examples and linking them within packages.json like:
+ * "react-native-library-name": "file:../"
+ * will cause problems with the metro bundler if the example will run via
+ * `react-native run-[ios|android]`. This will result in an error as the metro
+ * bundler will find multiple versions for the same module while resolving it.
+ * The reason for that is that if the library is installed it also copies in the
+ * example folder itself as well as the node_modules folder of the library
+ * although their are defined in .npmignore and should be ignored in theory.
+ *
+ * This postinstall script removes the node_modules folder as well as all
+ * entries from the libraries .npmignore file within the examples node_modules
+ * folder after the library was installed. This should resolve the metro
+ * bundler issue mentioned above.
+ *
+ * It is expected this scripts lives in the libraries root folder within a
+ * scripts folder. As first parameter the relative path to the libraries
+ * folder within the example's node_modules folder may be provided.
+ * This script will determine the path from this project's package.json file
+ * if no such relative path is provided.
+ * An example's package.json entry could look like:
+ * "postinstall": "node ../scripts/examples_postinstall.js node_modules/react-native-library-name/"
+ */
+
+'use strict'
+
+const fs = require('fs')
+const path = require('path')
+
+/// Delete all files and directories for the given path
+const removeFileDirectoryRecursively = fileDirPath => {
+  // Remove file
+  if (!fs.lstatSync(fileDirPath).isDirectory()) {
+    fs.unlinkSync(fileDirPath)
+    return
+  }
+
+  // Go down the directory an remove each file / directory recursively
+  fs.readdirSync(fileDirPath).forEach(entry => {
+    const entryPath = path.join(fileDirPath, entry)
+    removeFileDirectoryRecursively(entryPath)
+  })
+  fs.rmdirSync(fileDirPath)
+}
+
+const removeFileDir = fileDirPath => {
+  try {
+    removeFileDirectoryRecursively(fileDirPath)
+    console.log(`Deleted: ${fileDirPath}`)
+  } catch (err) {
+    console.log(`Error deleting ${fileDirPath}: ${err.message}`)
+  }
+}
+
+/// Remove example/node_modules/react-native-library-name/node_modules directory
+const removeLibraryNodeModulesPath = nodeModulesPath => {
+  if (!fs.existsSync(nodeModulesPath)) {
+    console.log(
+      `No node_modules found at ${nodeModulesPath}. Skipping delete.`
+    )
+    return
+  }
+
+  removeFileDir(nodeModulesPath)
+}
+
+/// Remove all entries from the .npmignore within example/node_modules/react-native-library-name/
+const removeLibraryNpmIgnorePaths = (npmIgnorePath, libraryNodeModulesPath) => {
+  if (!fs.existsSync(npmIgnorePath)) {
+    console.log(
+      `No .npmignore found at ${npmIgnorePath}. Skipping deleting content.`
+    )
+    return
+  }
+
+  fs.readFileSync(npmIgnorePath, 'utf8')
+    .split(/\r?\n/)
+    .forEach(entry => {
+      if (entry.length === 0) {
+        return
+      }
+
+      const npmIgnoreLibraryNodeModulesEntryPath = path.resolve(
+        libraryNodeModulesPath,
+        entry
+      )
+      if (!fs.existsSync(npmIgnoreLibraryNodeModulesEntryPath)) {
+        return
+      }
+
+      removeFileDir(npmIgnoreLibraryNodeModulesEntryPath)
+    })
+};
+
+// Main start sweeping process
+(() => {
+  // Read out dir of example project
+  const cwd = process.cwd()
+
+  console.log(`Starting postinstall cleanup for ${cwd}`)
+
+  // Resolve the React Native library's path within the example's node_modules directory
+  const libraryNodeModulesPath =
+    process.argv.length > 2
+      ? path.resolve(cwd, process.argv[2])
+      : path.resolve(cwd, 'node_modules', require('../package.json').name)
+
+  console.log('Removing nested node_modules directory...')
+  const nodeModulesPath = path.resolve(libraryNodeModulesPath, 'node_modules')
+  removeLibraryNodeModulesPath(nodeModulesPath)
+
+  console.log('Processing .npmignore entries...')
+  const npmIgnorePath = path.resolve(__dirname, '../.npmignore')
+  removeLibraryNpmIgnorePaths(npmIgnorePath, libraryNodeModulesPath)
+})()