Bug 1615781 - Enable nullish coalescing and optional chaining operators when parsing console expression. r=loganfsmyth.

Since both operators are now supported in Firefox,
we should make sure we can use them in top-level
await expression in the console.
Unit tests are added to ensure this works as expected.

Differential Revision: https://phabricator.services.mozilla.com/D63043

--HG--
extra : moz-landing-system : lando

devtools/client/debugger/dist/parser-worker.js

@@ -7156,7 +7156,7 @@ function parseVueScript(code) {
 function parseConsoleScript(text, opts) {
   try {
     return _parse(text, {
-      plugins: ["objectRestSpread", "dynamicImport"],
+      plugins: ["objectRestSpread", "dynamicImport", "nullishCoalescingOperator", "optionalChaining"],
       ...opts,
       allowAwaitOutsideFunction: true
     });

devtools/client/debugger/src/workers/parser/tests/mapExpression.spec.js

@@ -522,6 +522,58 @@ describe("mapExpression", () => {
         originalExpression: false,
       },
     },
+    {
+      name: "await (nullish coalesce operator)",
+      expression: "await x; true ?? false",
+      newExpression: `(async () => {
+          await x;
+          return true ?? false;
+        })()`,
+      shouldMapBindings: false,
+      expectedMapped: {
+        await: true,
+        bindings: false,
+        originalExpression: false,
+      },
+    },
+    {
+      name: "await (optional chaining operator)",
+      expression: "await x; x?.y?.z",
+      newExpression: `(async () => {
+          await x;
+          return x?.y?.z;
+        })()`,
+      shouldMapBindings: false,
+      expectedMapped: {
+        await: true,
+        bindings: false,
+        originalExpression: false,
+      },
+    },
+    {
+      name: "await (async function declaration with nullish coalesce operator)",
+      expression: "async function coalesce(x) { await x; return x ?? false; }",
+      newExpression:
+        "async function coalesce(x) { await x; return x ?? false; }",
+      shouldMapBindings: false,
+      expectedMapped: {
+        await: false,
+        bindings: false,
+        originalExpression: false,
+      },
+    },
+    {
+      name:
+        "await (async function declaration with optional chaining operator)",
+      expression: "async function chain(x) { await x; return x?.y?.z; }",
+      newExpression: "async function chain(x) { await x; return x?.y?.z; }",
+      shouldMapBindings: false,
+      expectedMapped: {
+        await: false,
+        bindings: false,
+        originalExpression: false,
+      },
+    },
     {
       name: "simple",
       expression: "a",

devtools/client/debugger/src/workers/parser/utils/ast.js

@@ -101,7 +101,12 @@ function parseVueScript(code) {
 export function parseConsoleScript(text: string, opts?: Object): Object | null {
   try {
     return _parse(text, {
-      plugins: ["objectRestSpread", "dynamicImport"],
+      plugins: [
+        "objectRestSpread",
+        "dynamicImport",
+        "nullishCoalescingOperator",
+        "optionalChaining",
+      ],
       ...opts,
       allowAwaitOutsideFunction: true,
     });