refactor(gatsby-transformer-remark): Refactors out Bluebird usage in transformer-remark (#29638)

Co-authored-by: Ward Peeters <ward@coding-tech.com>

Author: lourd

packages/gatsby-transformer-remark/package.json

@@ -8,7 +8,6 @@
   },
   "dependencies": {
     "@babel/runtime": "^7.12.5",
-    "bluebird": "^3.7.2",
     "gatsby-core-utils": "^2.1.0-next.1",
     "gray-matter": "^4.0.2",
     "hast-util-raw": "^4.0.0",

packages/gatsby-transformer-remark/src/__tests__/on-node-create.js

@@ -1,4 +1,3 @@
-const Promise = require(`bluebird`)
 const _ = require(`lodash`)
 const { onCreateNode } = require(`../on-node-create`)
 const { graphql } = require(`gatsby/graphql`)

packages/gatsby-transformer-remark/src/extend-node-type.js

@@ -6,7 +6,6 @@ const toHAST = require(`mdast-util-to-hast`)
 const hastToHTML = require(`hast-util-to-html`)
 const mdastToToc = require(`mdast-util-toc`)
 const mdastToString = require(`mdast-util-to-string`)
-const Promise = require(`bluebird`)
 const unified = require(`unified`)
 const parse = require(`remark-parse`)
 const stringify = require(`remark-stringify`)
@@ -116,7 +115,7 @@ module.exports = function remarkExtendNodeType(
     }
     let remark = new Remark().data(`settings`, remarkOptions)
 
-    for (let plugin of pluginOptions.plugins) {
+    for (const plugin of pluginOptions.plugins) {
       const requiredPlugin = require(plugin.resolve)
       if (_.isFunction(requiredPlugin.setParserPlugins)) {
         for (let parserPlugin of requiredPlugin.setParserPlugins(
@@ -193,8 +192,8 @@ module.exports = function remarkExtendNodeType(
       if (process.env.NODE_ENV !== `production` || !fileNodes) {
         fileNodes = getNodesByType(`File`)
       }
-      // Use Bluebird's Promise function "each" to run remark plugins serially.
-      await Promise.each(pluginOptions.plugins, plugin => {
+      // Use a for loop to run remark plugins serially.
+      for (const plugin of pluginOptions.plugins) {
         const requiredPlugin = require(plugin.resolve)
         // Allow both exports = function(), and exports.default = function()
         const defaultFunction = _.isFunction(requiredPlugin)
@@ -204,7 +203,7 @@ module.exports = function remarkExtendNodeType(
           : undefined
 
         if (defaultFunction) {
-          return defaultFunction(
+          await defaultFunction(
             {
               markdownAST,
               markdownNode,
@@ -220,10 +219,8 @@ module.exports = function remarkExtendNodeType(
             },
             plugin.pluginOptions
           )
-        } else {
-          return Promise.resolve()
         }
-      })
+      }
 
       return markdownAST
     }
@@ -236,7 +233,7 @@ module.exports = function remarkExtendNodeType(
       // Execute the remark plugins that can mutate the node
       // before parsing its content
       //
-      // Use Bluebird's Promise function "each" to run remark plugins serially.
+      // Use for loop to run remark plugins serially.
       for (const plugin of pluginOptions.plugins) {
         const requiredPlugin = require(plugin.resolve)
         if (typeof requiredPlugin.mutateSource === `function`) {