From f6c2acc3983cfbd57d2de39092e6398960930003 Mon Sep 17 00:00:00 2001
From: Andy Edwards <jedwards@fastmail.com>
Date: Mon, 21 Dec 2020 14:13:27 -0600
Subject: [PATCH] feat: create template.asyncExpression

---
 src/__tests__/template-test.js | 10 +++++++++-
 src/template.js                | 22 +++++++++++++++++++++-
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/__tests__/template-test.js b/src/__tests__/template-test.js
index 6e7b6940..fb614b1a 100644
--- a/src/__tests__/template-test.js
+++ b/src/__tests__/template-test.js
@@ -108,7 +108,6 @@ while (i < 10) {
     )
     .toEqual(expected);
   });
-
   it('correctly parses expressions without any interpolation', () => {
     const expected = 'function() {}';
 
@@ -121,6 +120,15 @@ while (i < 10) {
     .toEqual(expected);
   });
 
+  for (const parser of ['babel', 'babylon', 'flow', 'ts', 'tsx']) {
+    it(`asyncExpression correctly parses expressions with await -- ${parser}`, () => {
+      const expected = '{\n  bar: await baz\n}'
+      const j = jscodeshift.withParser(parser)
+
+      expect(j(j.template.asyncExpression`{\n  bar: await baz\n}`).toSource()).toEqual(expected)
+    })
+  }
+
   describe('explode arrays', () => {
 
     it('explodes arrays in function definitions', () => {
diff --git a/src/template.js b/src/template.js
index d2c0f0d2..f55cc971 100644
--- a/src/template.js
+++ b/src/template.js
@@ -149,5 +149,25 @@ module.exports = function withParser(parser) {
     return expression;
   }
 
-  return {statements, statement, expression};
+  function asyncExpression(template/*, ...nodes*/) {
+    template = Array.from(template);
+    if (template.length > 0) {
+      template[0] = 'async () => (' + template[0];
+      template[template.length - 1] += ')';
+    }
+
+    const expression = statement.apply(
+      null,
+      [template].concat(Array.from(arguments).slice(1))
+    ).expression.body;
+
+    // Remove added parens
+    if (expression.extra) {
+      expression.extra.parenthesized = false;
+    }
+
+    return expression;
+  }
+
+  return {statements, statement, expression, asyncExpression};
 }