refactor: add parseDo method

babel · Jul 23, 2020 · 10209b7 · 10209b7
1 parent c21bee5
commit 10209b7
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Showing 2 changed files with 18 additions and 8 deletions.
diff --git a/packages/babel-parser/src/parser/expression.js b/packages/babel-parser/src/parser/expression.js
@@ -1023,14 +1023,7 @@ export default class ExpressionParser extends LValParser {
       }
 
       case tt._do: {
-        this.expectPlugin("doExpressions");
-        const node = this.startNode();
-        this.next();
-        const oldLabels = this.state.labels;
-        this.state.labels = [];
-        node.body = this.parseBlock();
-        this.state.labels = oldLabels;
-        return this.finishNode(node, "DoExpression");
+        return this.parseDo();
       }
 
       case tt.regexp: {
@@ -1237,6 +1230,18 @@ export default class ExpressionParser extends LValParser {
     return node;
   }
 
+  // https://github.com/tc39/proposal-do-expressions
+  parseDo(): N.DoExpression {
+    this.expectPlugin("doExpressions");
+    const node = this.startNode();
+    this.next(); // eat `do`
+    const oldLabels = this.state.labels;
+    this.state.labels = [];
+    node.body = this.parseBlock();
+    this.state.labels = oldLabels;
+    return this.finishNode(node, "DoExpression");
+  }
+
   // Parse the `super` keyword
   parseSuper(): N.Super {
     const node = this.startNode();

diff --git a/packages/babel-parser/src/types.js b/packages/babel-parser/src/types.js
@@ -389,6 +389,11 @@ export type ArrayExpression = NodeBase & {
   elements: $ReadOnlyArray<?(Expression | SpreadElement)>,
 };
 
+export type DoExpression = NodeBase & {
+  type: "DoExpression",
+  body: ?BlockStatement,
+};
+
 export type TupleExpression = NodeBase & {
   type: "TupleExpression",
   elements: $ReadOnlyArray<?(Expression | SpreadElement)>,