Enable optional chaining and nullish coalescing plugins (#10494)

* Add optional chaining plugin

* Nullish coalescing

.flowconfig

@@ -24,4 +24,6 @@ suppress_comment= \\(.\\|\n\\)*\\$FlowIgnore
 suppress_type=$FlowFixMe
 suppress_type=$FlowSubtype
 esproposal.export_star_as=enable
+esproposal.optional_chaining=enable
+esproposal.nullish_coalescing=enable
 module.name_mapper='^@babel\/\([a-zA-Z0-9_\-]+\)$' -> '<PROJECT_ROOT>/packages/babel-\1/src/index'

babel.config.js

@@ -77,6 +77,8 @@ module.exports = function(api) {
         "@babel/proposal-object-rest-spread",
         { useBuiltIns: true, loose: true },
       ],
+      "@babel/plugin-proposal-optional-chaining",
+      "@babel/plugin-proposal-nullish-coalescing-operator",
 
       // Explicitly use the lazy version of CommonJS modules.
       convertESM ? ["@babel/transform-modules-commonjs", { lazy: true }] : null,

package.json

@@ -14,7 +14,9 @@
     "@babel/eslint-plugin-development": "^1.0.1",
     "@babel/plugin-proposal-class-properties": "^7.5.5",
     "@babel/plugin-proposal-export-namespace-from": "^7.5.2",
+    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.4.4",
     "@babel/plugin-proposal-numeric-separator": "^7.2.0",
+    "@babel/plugin-proposal-optional-chaining": "^7.6.0",
     "@babel/plugin-transform-modules-commonjs": "^7.6.0",
     "@babel/plugin-transform-runtime": "^7.6.0",
     "@babel/preset-env": "^7.6.0",

yarn.lock

@@ -293,6 +293,14 @@
     "@babel/helper-plugin-utils" "^7.0.0"
     "@babel/plugin-syntax-json-strings" "^7.2.0"
 
+"@babel/plugin-proposal-nullish-coalescing-operator@^7.4.4":
+  version "7.4.4"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-nullish-coalescing-operator/-/plugin-proposal-nullish-coalescing-operator-7.4.4.tgz#41c360d59481d88e0ce3a3f837df10121a769b39"
+  integrity sha512-Amph7Epui1Dh/xxUxS2+K22/MUi6+6JVTvy3P58tja3B6yKTSjwwx0/d83rF7551D6PVSSoplQb8GCwqec7HRw==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+    "@babel/plugin-syntax-nullish-coalescing-operator" "^7.2.0"
+
 "@babel/plugin-proposal-numeric-separator@^7.2.0":
   version "7.2.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-numeric-separator/-/plugin-proposal-numeric-separator-7.2.0.tgz#646854daf4cd22fd6733f6076013a936310443ac"
@@ -317,6 +325,14 @@
     "@babel/helper-plugin-utils" "^7.0.0"
     "@babel/plugin-syntax-optional-catch-binding" "^7.2.0"
 
+"@babel/plugin-proposal-optional-chaining@^7.6.0":
+  version "7.6.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-optional-chaining/-/plugin-proposal-optional-chaining-7.6.0.tgz#e9bf1f9b9ba10c77c033082da75f068389041af8"
+  integrity sha512-kj4gkZ6qUggkprRq3Uh5KP8XnE1MdIO0J7MhdDX8+rAbB6dJ2UrensGIS+0NPZAaaJ1Vr0PN6oLUgXMU1uMcSg==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+    "@babel/plugin-syntax-optional-chaining" "^7.2.0"
+
 "@babel/plugin-proposal-unicode-property-regex@^7.4.4":
   version "7.4.4"
   resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-unicode-property-regex/-/plugin-proposal-unicode-property-regex-7.4.4.tgz#501ffd9826c0b91da22690720722ac7cb1ca9c78"
@@ -361,6 +377,13 @@
   dependencies:
     "@babel/helper-plugin-utils" "^7.0.0"
 
+"@babel/plugin-syntax-nullish-coalescing-operator@^7.2.0":
+  version "7.2.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-syntax-nullish-coalescing-operator/-/plugin-syntax-nullish-coalescing-operator-7.2.0.tgz#f75083dfd5ade73e783db729bbd87e7b9efb7624"
+  integrity sha512-lRCEaKE+LTxDQtgbYajI04ddt6WW0WJq57xqkAZ+s11h4YgfRHhVA/Y2VhfPzzFD4qeLHWg32DMp9HooY4Kqlg==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+
 "@babel/plugin-syntax-numeric-separator@^7.2.0":
   version "7.2.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-syntax-numeric-separator/-/plugin-syntax-numeric-separator-7.2.0.tgz#7470fe070c2944469a756752a69a6963135018be"
@@ -382,6 +405,13 @@
   dependencies:
     "@babel/helper-plugin-utils" "^7.0.0"
 
+"@babel/plugin-syntax-optional-chaining@^7.2.0":
+  version "7.2.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-syntax-optional-chaining/-/plugin-syntax-optional-chaining-7.2.0.tgz#a59d6ae8c167e7608eaa443fda9fa8fa6bf21dff"
+  integrity sha512-HtGCtvp5Uq/jH/WNUPkK6b7rufnCPLLlDAFN7cmACoIjaOOiXxUt3SswU5loHqrhtqTsa/WoLQ1OQ1AGuZqaWA==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+
 "@babel/plugin-transform-arrow-functions@^7.2.0":
   version "7.2.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-transform-arrow-functions/-/plugin-transform-arrow-functions-7.2.0.tgz#9aeafbe4d6ffc6563bf8f8372091628f00779550"