Fix: Handle async/await (fixes #119) (#129)

Author: flying-sheep

lib/ast-converter.js

@@ -105,6 +105,17 @@ function isESTreeClassMember(node) {
     return node.kind !== SyntaxKind.SemicolonClassElement;
 }
 
+/**
+ * Returns true if the given node is an async function
+ * @param  {TSNode}  node TypeScript AST node
+ * @returns {boolean}     is an async function
+ */
+function isAsyncFunction(node) {
+    return !!node.modifiers && !!node.modifiers.length && node.modifiers.some(function(modifier) {
+        return modifier.kind === SyntaxKind.AsyncKeyword;
+    });
+}
+
 /**
  * Returns true if the given TSToken is a comma
  * @param  {TSToken}  token the TypeScript token
@@ -852,6 +863,7 @@ module.exports = function(ast, extra) {
                     id: convertChild(node.name),
                     generator: !!node.asteriskToken,
                     expression: false,
+                    async: isAsyncFunction(node),
                     params: node.parameters.map(convertChild),
                     body: convertChild(node.body)
                 });
@@ -1057,6 +1069,7 @@ module.exports = function(ast, extra) {
                         id: null,
                         generator: false,
                         expression: false,
+                        async: isAsyncFunction(node),
                         body: convertChild(node.body),
                         range: [ node.parameters.pos - 1, result.range[1]],
                         loc: {
@@ -1158,6 +1171,7 @@ module.exports = function(ast, extra) {
                         }),
                         generator: false,
                         expression: false,
+                        async: false,
                         body: convertChild(node.body),
                         range: [ result.range[0] + constructorStartOffset, result.range[1]],
                         loc: {
@@ -1226,6 +1240,7 @@ module.exports = function(ast, extra) {
                     generator: !!node.asteriskToken,
                     params: node.parameters.map(convertChild),
                     body: convertChild(node.body),
+                    async: isAsyncFunction(node),
                     expression: false
                 });
                 // Process returnType
@@ -1308,6 +1323,7 @@ module.exports = function(ast, extra) {
                     id: null,
                     params: node.parameters.map(convertChild),
                     body: convertChild(node.body),
+                    async: isAsyncFunction(node),
                     expression: node.body.kind !== SyntaxKind.Block
                 });
                 // Process returnType
@@ -1328,6 +1344,13 @@ module.exports = function(ast, extra) {
                 });
                 break;
 
+            case SyntaxKind.AwaitExpression:
+                assign(result, {
+                    type: "AwaitExpression",
+                    expression: convertChild(node.expression)
+                });
+                break;
+
             // Template Literals
 
             case SyntaxKind.NoSubstitutionTemplateLiteral:

lib/ast-node-types.js

@@ -23,6 +23,7 @@ module.exports = {
     ArrayExpression: "ArrayExpression",
     ArrayPattern: "ArrayPattern",
     ArrowFunctionExpression: "ArrowFunctionExpression",
+    AwaitExpression: "AwaitExpression",
     BlockStatement: "BlockStatement",
     BinaryExpression: "BinaryExpression",
     BreakStatement: "BreakStatement",

tests/fixtures/attach-comments/export-default-anonymous-class.result.js

@@ -56,6 +56,7 @@ module.exports = {
                                 },
                                 "generator": false,
                                 "expression": false,
+                                "async": false,
                                 "range": [
                                     110,
                                     119

tests/fixtures/attach-comments/surrounding-call-comments.result.js

@@ -123,6 +123,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],

tests/fixtures/attach-comments/surrounding-debugger-comments.result.js

@@ -87,6 +87,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],

tests/fixtures/attach-comments/surrounding-return-comments.result.js

@@ -88,6 +88,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],

tests/fixtures/attach-comments/surrounding-throw-comments.result.js

@@ -106,6 +106,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],

tests/fixtures/attach-comments/surrounding-while-loop-comments.result.js

@@ -51,6 +51,7 @@ module.exports = {
             },
             "generator": false,
             "expression": false,
+            "async": false,
             "params": [],
             "body": {
                 "type": "BlockStatement",

tests/fixtures/attach-comments/switch-fallthrough-comment-in-function.result.js

@@ -254,6 +254,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],

tests/fixtures/attach-comments/switch-no-default-comment-in-function.result.js

@@ -238,6 +238,7 @@ module.exports = {
                 ]
             },
             "expression": false,
+            "async": false,
             "generator": false
         }
     ],