fix: add ESM version

.eslintignore

@@ -3,3 +3,4 @@ coverage/*
 documentation/*
 node_modules/*
 docs/*
+esm/*

.gitignore

@@ -4,3 +4,4 @@ coverage
 npm-debug.log
 yarn-error.log
 /docs
+/esm

package.json

@@ -15,11 +15,15 @@
   ],
   "dependencies": {},
   "devDependencies": {
+    "@babel/core": "^7.10.5",
+    "@babel/preset-env": "^7.10.4",
+    "5to6-codemod": "1.8.0",
     "docdash": "homer0/docdash#semver:^2.0.0",
     "eslint": "^7.5.0",
     "eslint-plugin-homer0": "^5.0.1",
     "husky": "^4.2.5",
     "jest": "^26.1.0",
+    "jscodeshift": "0.10.0",
     "jsdoc": "^3.6.4",
     "jsdoc-ts-utils": "^1.0.0",
     "leasot": "^11.1.0",
@@ -32,6 +36,7 @@
   },
   "main": "src/index.js",
   "scripts": {
+    "prepare": "./utils/scripts/prepare",
     "test": "./utils/scripts/test",
     "lint": "./utils/scripts/lint",
     "lint:all": "./utils/scripts/lint-all",

utils/scripts/prepare

@@ -0,0 +1,46 @@
+#!/bin/bash -e
+
+##############################
+# CONFIG
+##############################
+
+# The path where the ESM build will be generated.
+OUTPUT_PATH="./esm"
+# The directory that needs to be copied and transpiled.
+SOURCE="./src"
+# The path to the transformations jscodeshift will use; this variable exists just to
+# avoid writing the long path on each transformation.
+CODEMODS_PATH="node_modules/5to6-codemod/transforms"
+# The list of transformations needed in order to make the code ESM compatible.
+#
+# - cjs: changes all 'require' statements to 'import'.
+# - exports: changes all `module.exports` statements to `export` .
+TRANSFORMATIONS=("cjs" "exports")
+
+##############################
+# EXECUTION
+##############################
+
+# Delete the output path if it already exists and create it again.
+rm -rf $OUTPUT_PATH && mkdir $OUTPUT_PATH;
+
+# Copy all the files that need transpilation. jscodeshift is a tool for codemods,
+# so it doesn't transpile from one place to another, so we first need to move the files
+# and then transform them.
+cp -R "$SOURCE/" "$OUTPUT_PATH";
+# for SOURCE in "${SOURCES[@]}";
+#   do cp -R "./$SOURCE" "$OUTPUT_PATH/$SOURCE";
+# done
+
+# Delete any hidden/configuration file that was copied during the previous step.
+find $OUTPUT_PATH -maxdepth 2 -type f -name ".*" -depth -delete;
+
+# jscodeshift doesn't allow for multiple transformations at once, that's why it needs
+# too iterate the list and apply one by one.
+for TRANSFORMATION in "${TRANSFORMATIONS[@]}";
+  do jscodeshift -t "$CODEMODS_PATH/$TRANSFORMATION.js" $OUTPUT_PATH;
+done
+
+# Add a `package.json` with the `type: 'module'` on the output directory so imports
+# from Node native ESM modules won't cause errors.
+echo "{ \"type\": \"module\" }" > "$OUTPUT_PATH/package.json";