diff --git a/lib/ast.js b/lib/ast.js
index 8700b4ba..da654606 100644
--- a/lib/ast.js
+++ b/lib/ast.js
@@ -445,7 +445,7 @@ var AST_PrefixedTemplateString = DEFNODE("PrefixedTemplateString", "template_str
         this.prefix._walk(visitor);
         this.template_string._walk(visitor);
     }
-})
+});
 
 var AST_TemplateString = DEFNODE("TemplateString", "segments", {
     $documentation: "A template string literal",
@@ -643,7 +643,7 @@ var AST_NameMapping = DEFNODE("NameMapping", "foreign_name name", {
             this.name._walk(visitor);
         });
     }
-})
+});
 
 var AST_Import = DEFNODE("Import", "imported_name imported_names module_name", {
     $documentation: "An `import` statement",
diff --git a/lib/mozilla-ast.js b/lib/mozilla-ast.js
index 41ba04f1..1676ee37 100644
--- a/lib/mozilla-ast.js
+++ b/lib/mozilla-ast.js
@@ -71,12 +71,88 @@
                 body: normalize_directives(M.body.map(from_moz))
             });
         },
+        ArrayPattern: function(M) {
+            return new AST_Destructuring({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                names: M.elements.map(function(elm) {
+                    if (elm === null) {
+                        return new AST_Hole();
+                    }
+                    return from_moz(elm);
+                }),
+                is_array: true
+            });
+        },
+        ObjectPattern: function(M) {
+            return new AST_Destructuring({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                names: M.properties.map(from_moz),
+                is_array: false
+            });
+        },
+        AssignmentPattern: function(M) {
+            return new AST_Binary({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                left: from_moz(M.left),
+                operator: "=",
+                right: from_moz(M.right)
+            });
+        },
+        SpreadElement: function(M) {
+            return new AST_Expansion({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                expression: from_moz(M.argument)
+            });
+        },
+        RestElement: function(M) {
+            return new AST_Expansion({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                expression: from_moz(M.argument)
+            });
+        },
+        TemplateElement: function(M) {
+            return new AST_TemplateSegment({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                value: M.value.cooked,
+                raw: M.value.raw
+            });
+        },
+        TemplateLiteral: function(M) {
+            var segments = [];
+            for (var i = 0; i < M.quasis.length; i++) {
+                segments.push(from_moz(M.quasis[i]));
+                if (M.expressions[i]) {
+                    segments.push(from_moz(M.expressions[i]));
+                }
+            }
+            return new AST_TemplateString({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                segments: segments
+            });
+        },
+        TaggedTemplateExpression: function(M) {
+            return new AST_PrefixedTemplateString({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                template_string: from_moz(M.quasi),
+                prefix: from_moz(M.tag)
+            });
+        },
         FunctionDeclaration: function(M) {
             return new AST_Defun({
                 start: my_start_token(M),
                 end: my_end_token(M),
                 name: from_moz(M.id),
                 argnames: M.params.map(from_moz),
+                is_generator: M.generator,
+                async: M.async,
                 body: normalize_directives(from_moz(M.body).body)
             });
         },
@@ -86,9 +162,20 @@
                 end: my_end_token(M),
                 name: from_moz(M.id),
                 argnames: M.params.map(from_moz),
+                is_generator: M.generator,
+                async: M.async,
                 body: normalize_directives(from_moz(M.body).body)
             });
         },
+        ArrowFunctionExpression: function(M) {
+            return new AST_Arrow({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                argnames: M.params.map(from_moz),
+                body: from_moz(M.body),
+                async: M.async,
+            });
+        },
         ExpressionStatement: function(M) {
             return new AST_SimpleStatement({
                 start: my_start_token(M),
@@ -112,18 +199,62 @@
         Property: function(M) {
             var key = M.key;
             var args = {
-                start    : my_start_token(key),
+                start    : my_start_token(key || M.value),
                 end      : my_end_token(M.value),
                 key      : key.type == "Identifier" ? key.name : key.value,
                 value    : from_moz(M.value)
             };
-            if (M.kind == "init") return new AST_ObjectKeyVal(args);
-            args.key = new AST_SymbolMethod({
-                name: args.key
-            });
+            if (M.computed) {
+                args.key = from_moz(M.key);
+            }
+            if (M.method) {
+                args.is_generator = M.value.generator;
+                args.async = M.value.async;
+                if (!M.computed) {
+                    args.key = new AST_SymbolMethod({ name: args.key });
+                } else {
+                    args.key = from_moz(M.key);
+                }
+                return new AST_ConciseMethod(args);
+            }
+            if (M.kind == "init") {
+                if (key.type != "Identifier" && key.type != "Literal") {
+                    args.key = from_moz(key);
+                }
+                return new AST_ObjectKeyVal(args);
+            }
+            if (typeof args.key === "string" || typeof args.key === "number") {
+                args.key = new AST_SymbolMethod({
+                    name: args.key
+                });
+            }
             args.value = new AST_Accessor(args.value);
             if (M.kind == "get") return new AST_ObjectGetter(args);
             if (M.kind == "set") return new AST_ObjectSetter(args);
+            if (M.kind == "method") {
+                args.async = M.value.async;
+                args.is_generator = M.value.generator;
+                args.quote = M.computed ? "\"" : null;
+                return new AST_ConciseMethod(args);
+            }
+        },
+        MethodDefinition: function(M) {
+            var args = {
+                start    : my_start_token(M),
+                end      : my_end_token(M),
+                key      : M.computed ? from_moz(M.key) : new AST_SymbolMethod({ name: M.key.name || M.key.value }),
+                value    : from_moz(M.value),
+                static   : M.static,
+            };
+            if (M.kind == "get") {
+                return new AST_ObjectGetter(args);
+            }
+            if (M.kind == "set") {
+                return new AST_ObjectSetter(args);
+            }
+            args.is_generator = M.value.generator;
+            args.async = M.value.async;
+            return new AST_ConciseMethod(args);
         },
         ArrayExpression: function(M) {
             return new AST_Array({
@@ -139,6 +270,9 @@
                 start      : my_start_token(M),
                 end        : my_end_token(M),
                 properties : M.properties.map(function(prop){
+                    if (prop.type === "SpreadElement") {
+                        return from_moz(prop);
+                    }
                     prop.type = "Property";
                     return from_moz(prop)
                 })
@@ -168,18 +302,98 @@
             });
         },
         VariableDeclaration: function(M) {
-            return new (M.kind === "const" ? AST_Const : AST_Var)({
+            return new (M.kind === "const" ? AST_Const :
+                        M.kind === "let" ? AST_Let : AST_Var)({
                 start       : my_start_token(M),
                 end         : my_end_token(M),
                 definitions : M.declarations.map(from_moz)
             });
         },
+        
+        ImportDeclaration: function(M) {
+            var imported_name = null;
+            var imported_names = null;
+            M.specifiers.forEach(function (specifier) {
+                if (specifier.type === "ImportSpecifier") {
+                    if (!imported_names) { imported_names = []; }
+                    imported_names.push(new AST_NameMapping({
+                        start: my_start_token(specifier),
+                        end: my_end_token(specifier),
+                        foreign_name: from_moz(specifier.imported),
+                        name: from_moz(specifier.local)
+                    }));
+                } else if (specifier.type === "ImportDefaultSpecifier") {
+                    imported_name = from_moz(specifier.local);
+                } else if (specifier.type === "ImportNamespaceSpecifier") {
+                    if (!imported_names) { imported_names = []; }
+                    imported_names.push(new AST_NameMapping({
+                        start: my_start_token(specifier),
+                        end: my_end_token(specifier),
+                        foreign_name: new AST_SymbolImportForeign({ name: "*" }),
+                        name: from_moz(specifier.local)
+                    }));
+                }
+            });
+            return new AST_Import({
+                start       : my_start_token(M),
+                end         : my_end_token(M),
+                imported_name: imported_name,
+                imported_names : imported_names,
+                module_name : from_moz(M.source)
+            })
+        },
+        ExportAllDeclaration: function(M) {
+            return new AST_Export({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                exported_names: [
+                    new AST_NameMapping({
+                        name: new AST_SymbolExportForeign({ name: "*" }),
+                        foreign_name: new AST_SymbolExportForeign({ name: "*" })
+                    })
+                ],
+                module_name: from_moz(M.source)
+            });
+        },
+        ExportNamedDeclaration: function(M) {
+            return new AST_Export({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                exported_definition: from_moz(M.declaration),
+                exported_names: M.specifiers && M.specifiers.length ? M.specifiers.map(function (specifier) {
+                    return new AST_NameMapping({
+                        foreign_name: from_moz(specifier.exported),
+                        name: from_moz(specifier.local)
+                    })
+                }) : null,
+                module_name: from_moz(M.source)
+            });
+        },
+        ExportDefaultDeclaration: function(M) {
+            return new AST_Export({
+                start: my_start_token(M),
+                end: my_end_token(M),
+                exported_value: from_moz(M.declaration),
+                is_default: true
+            });
+        },
         Literal: function(M) {
             var val = M.value, args = {
                 start  : my_start_token(M),
                 end    : my_end_token(M)
             };
             if (val === null) return new AST_Null(args);
+            var rx = M.regex;
+            if (rx && rx.pattern) {
+                // RegExpLiteral as per ESTree AST spec
+                args.value = new RegExp(rx.pattern, rx.flags);
+                args.value.raw_source = rx.pattern;
+                return new AST_RegExp(args);
+            } else if (rx) {
+                // support legacy RegExp
+                args.value = M.regex && M.raw ? M.raw : val;
+                return new AST_RegExp(args);
+            }
             switch (typeof val) {
               case "string":
                 args.value = val;
@@ -189,24 +403,29 @@
                 return new AST_Number(args);
               case "boolean":
                 return new (val ? AST_True : AST_False)(args);
-              default:
-                var rx = M.regex;
-                if (rx && rx.pattern) {
-                    // RegExpLiteral as per ESTree AST spec
-                    args.value = new RegExp(rx.pattern, rx.flags).toString();
-                } else {
-                    // support legacy RegExp
-                    args.value = M.regex && M.raw ? M.raw : val;
-                }
-                return new AST_RegExp(args);
+            }
+        },
+        MetaProperty: function(M) {
+            if (M.meta.name === "new" && M.property.name === "target") {
+                return new AST_NewTarget({
+                    start: my_start_token(M),
+                    end: my_end_token(M)
+                });
             }
         },
         Identifier: function(M) {
             var p = FROM_MOZ_STACK[FROM_MOZ_STACK.length - 2];
             return new (  p.type == "LabeledStatement" ? AST_Label
-                        : p.type == "VariableDeclarator" && p.id === M ? (p.kind == "const" ? AST_SymbolConst : AST_SymbolVar)
+                        : p.type == "VariableDeclarator" && p.id === M ? (p.kind == "const" ? AST_SymbolConst : p.kind == "let" ? AST_SymbolLet : AST_SymbolVar)
+                        : /Import.*Specifier/.test(p.type) ? (p.local === M ? AST_SymbolImport : AST_SymbolImportForeign)
+                        : p.type == "ExportSpecifier" ? (p.local === M ? AST_SymbolExport : AST_SymbolExportForeign)
                         : p.type == "FunctionExpression" ? (p.id === M ? AST_SymbolLambda : AST_SymbolFunarg)
                         : p.type == "FunctionDeclaration" ? (p.id === M ? AST_SymbolDefun : AST_SymbolFunarg)
+                        : p.type == "ArrowFunctionExpression" ? (p.params.indexOf(M) !== -1) ? AST_SymbolFunarg : AST_SymbolRef
+                        : p.type == "ClassExpression" ? (p.id === M ? AST_SymbolClass : AST_SymbolRef)
+                        : p.type == "Property" ? (p.key === M && p.computed || p.value === M ? AST_SymbolRef : AST_SymbolMethod)
+                        : p.type == "ClassDeclaration" ? (p.id === M ? AST_SymbolDefClass : AST_SymbolRef)
+                        : p.type == "MethodDefinition" ? (p.computed ? AST_SymbolRef : AST_SymbolMethod)
                         : p.type == "CatchClause" ? AST_SymbolCatch
                         : p.type == "BreakStatement" || p.type == "ContinueStatement" ? AST_LabelRef
                         : AST_SymbolRef)({
@@ -229,6 +448,17 @@
         });
     };
 
+    MOZ_TO_ME.ClassDeclaration =
+    MOZ_TO_ME.ClassExpression = function From_Moz_Class(M) {
+        return new (M.type === "ClassDeclaration" ? AST_DefClass : AST_ClassExpression)({
+            start    : my_start_token(M),
+            end      : my_end_token(M),
+            name     : from_moz(M.id),
+            extends  : from_moz(M.superClass),
+            properties: M.body.body.map(from_moz)
+        });
+    };
+
     map("EmptyStatement", AST_EmptyStatement);
     map("BlockStatement", AST_BlockStatement, "body@body");
     map("IfStatement", AST_If, "test>condition, consequent>body, alternate>alternative");
@@ -243,11 +473,15 @@
     map("DoWhileStatement", AST_Do, "test>condition, body>body");
     map("ForStatement", AST_For, "init>init, test>condition, update>step, body>body");
     map("ForInStatement", AST_ForIn, "left>init, right>object, body>body");
+    map("ForOfStatement", AST_ForOf, "left>init, right>object, body>body");
+    map("AwaitExpression", AST_Await, "argument>expression");
+    map("YieldExpression", AST_Yield, "argument>expression, delegate=is_star");
     map("DebuggerStatement", AST_Debugger);
     map("VariableDeclarator", AST_VarDef, "id>name, init>value");
     map("CatchClause", AST_Catch, "param>argname, body%body");
 
     map("ThisExpression", AST_This);
+    map("SuperExpression", AST_Super);
     map("BinaryExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("LogicalExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("AssignmentExpression", AST_Assign, "operator=operator, left>left, right>right");
@@ -259,24 +493,95 @@
         return to_moz_scope("Program", M);
     });
 
+    def_to_moz(AST_Expansion, function To_Moz_Spread(M, parent) {
+        return {
+            type: to_moz_in_destructuring() ? "RestElement" : "SpreadElement",
+            argument: to_moz(M.expression)
+        };
+    });
+
+    def_to_moz(AST_PrefixedTemplateString, function To_Moz_TaggedTemplateExpression(M) {
+        return {
+            type: "TaggedTemplateExpression",
+            tag: to_moz(M.prefix),
+            quasi: to_moz(M.template_string)
+        };
+    });
+
+    def_to_moz(AST_TemplateString, function To_Moz_TemplateLiteral(M) {
+        var quasis = [];
+        var expressions = [];
+        for (var i = 0; i < M.segments.length; i++) {
+            if (i % 2 !== 0) {
+                expressions.push(to_moz(M.segments[i]));
+            } else {
+                quasis.push({
+                    type: "TemplateElement",
+                    value: {
+                        raw: M.segments[i].raw,
+                        cooked: M.segments[i].value
+                    },
+                    tail: i === M.segments.length - 1
+                });
+            }
+        }
+        return {
+            type: "TemplateLiteral",
+            quasis: quasis,
+            expressions: expressions
+        };
+    });
+
     def_to_moz(AST_Defun, function To_Moz_FunctionDeclaration(M) {
         return {
             type: "FunctionDeclaration",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
+            generator: M.is_generator,
+            async: M.async,
             body: to_moz_scope("BlockStatement", M)
         }
     });
 
-    def_to_moz(AST_Function, function To_Moz_FunctionExpression(M) {
+    def_to_moz(AST_Function, function To_Moz_FunctionExpression(M, parent) {
+        var is_generator = parent.is_generator !== undefined ?
+            parent.is_generator : M.is_generator
         return {
             type: "FunctionExpression",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
+            generator: is_generator,
+            async: M.async,
             body: to_moz_scope("BlockStatement", M)
         }
     });
 
+    def_to_moz(AST_Arrow, function To_Moz_ArrowFunctionExpression(M) {
+        var body = M.body instanceof Array ? {
+            type: "BlockStatement",
+            body: M.body.map(to_moz)
+        } : to_moz(M.body);
+        return {
+            type: "ArrowFunctionExpression",
+            params: M.argnames.map(to_moz),
+            async: M.async,
+            body: body
+        }
+    });
+
+    def_to_moz(AST_Destructuring, function To_Moz_ObjectPattern(M) {
+        if (M.is_array) {
+            return {
+                type: "ArrayPattern",
+                elements: M.names.map(to_moz)
+            }
+        }
+        return {
+            type: "ObjectPattern",
+            properties: M.names.map(to_moz)
+        };
+    });
+
     def_to_moz(AST_Directive, function To_Moz_Directive(M) {
         return {
             type: "ExpressionStatement",
@@ -324,11 +629,69 @@
     def_to_moz(AST_Definitions, function To_Moz_VariableDeclaration(M) {
         return {
             type: "VariableDeclaration",
-            kind: M instanceof AST_Const ? "const" : "var",
+            kind:
+                M instanceof AST_Const ? "const" :
+                M instanceof AST_Let ? "let" : "var",
             declarations: M.definitions.map(to_moz)
         };
     });
 
+    def_to_moz(AST_Export, function To_Moz_ExportDeclaration(M) {
+        if (M.exported_names) {
+            if (M.exported_names[0].name.name === "*") {
+                return {
+                    type: "ExportAllDeclaration",
+                    source: to_moz(M.module_name)
+                };
+            }
+            return {
+                type: "ExportNamedDeclaration",
+                specifiers: M.exported_names.map(function (name_mapping) {
+                    return {
+                        type: "ExportSpecifier",
+                        exported: to_moz(name_mapping.foreign_name),
+                        local: to_moz(name_mapping.name)
+                    };
+                }),
+                declaration: to_moz(M.exported_definition),
+                source: to_moz(M.module_name)
+            };
+        }
+        return {
+            type: M.is_default ? "ExportDefaultDeclaration" : "ExportNamedDeclaration",
+            declaration: to_moz(M.exported_value || M.exported_definition)
+        };
+    });
+
+    def_to_moz(AST_Import, function To_Moz_ImportDeclaration(M) {
+        var specifiers = [];
+        if (M.imported_name) {
+            specifiers.push({
+                type: "ImportDefaultSpecifier",
+                local: to_moz(M.imported_name)
+            });
+        }
+        if (M.imported_names && M.imported_names[0].foreign_name.name === '*') {
+            specifiers.push({
+                type: "ImportNamespaceSpecifier",
+                local: to_moz(M.imported_names[0].name)
+            });
+        } else if (M.imported_names) {
+            M.imported_names.forEach(function(name_mapping) {
+                specifiers.push({
+                    type: "ImportSpecifier",
+                    local: to_moz(name_mapping.name),
+                    imported: to_moz(name_mapping.foreign_name)
+                });
+            });
+        }
+        return {
+            type: "ImportDeclaration",
+            specifiers: specifiers,
+            source: to_moz(M.module_name)
+        }
+    });
+
     def_to_moz(AST_Sequence, function To_Moz_SequenceExpression(M) {
         return {
             type: "SequenceExpression",
@@ -356,6 +719,13 @@
     });
 
     def_to_moz(AST_Binary, function To_Moz_BinaryExpression(M) {
+        if (M.operator == "=" && to_moz_in_destructuring()) {
+            return {
+                type: "AssignmentPattern",
+                left: to_moz(M.left),
+                right: to_moz(M.right)
+            };
+        }
         return {
             type: M.operator == "&&" || M.operator == "||" ? "LogicalExpression" : "BinaryExpression",
             left: to_moz(M.left),
@@ -378,14 +748,29 @@
         };
     });
 
-    def_to_moz(AST_ObjectProperty, function To_Moz_Property(M) {
-        var key = {
-            type: "Literal",
-            value: M.key instanceof AST_SymbolMethod ? M.key.name : M.key
+    def_to_moz(AST_ObjectProperty, function To_Moz_Property(M, parent) {
+        var key = M.key instanceof AST_Node ? to_moz(M.key) : {
+            type: "Identifier",
+            value: M.key
         };
+        if (typeof M.key === "number") {
+            key = {
+                type: "Literal",
+                value: Number(M.key)
+            };
+        }
+        if (typeof M.key === "string") {
+            key = {
+                type: "Identifier",
+                name: M.key
+            };
+        }
         var kind;
+        var string_or_num = typeof M.key === "string" || typeof M.key === "number";
+        var computed = string_or_num ? false : !(M.key instanceof AST_Symbol) || M.key instanceof AST_SymbolRef;
         if (M instanceof AST_ObjectKeyVal) {
             kind = "init";
+            computed = !string_or_num;
         } else
         if (M instanceof AST_ObjectGetter) {
             kind = "get";
@@ -393,15 +778,81 @@
         if (M instanceof AST_ObjectSetter) {
             kind = "set";
         }
+        if (parent instanceof AST_Class) {
+            return {
+                type: "MethodDefinition",
+                computed: computed,
+                kind: kind,
+                static: M.static,
+                key: to_moz(M.key),
+                value: to_moz(M.value)
+            };
+        }
         return {
             type: "Property",
+            computed: computed,
             kind: kind,
             key: key,
             value: to_moz(M.value)
         };
     });
 
-    def_to_moz(AST_Symbol, function To_Moz_Identifier(M) {
+    def_to_moz(AST_ConciseMethod, function To_Moz_MethodDefinition(M, parent) {
+        if (parent instanceof AST_Object) {
+            return {
+                type: "Property",
+                computed: !(M.key instanceof AST_Symbol) || M.key instanceof AST_SymbolRef,
+                kind: "init",
+                method: true,
+                shorthand: false,
+                key: to_moz(M.key),
+                value: to_moz(M.value)
+            };
+        }
+        return {
+            type: "MethodDefinition",
+            computed: !(M.key instanceof AST_Symbol) || M.key instanceof AST_SymbolRef,
+            kind: M.key === "constructor" ? "constructor" : "method",
+            static: M.static,
+            key: to_moz(M.key),
+            value: to_moz(M.value)
+        };
+    });
+
+    def_to_moz(AST_Class, function To_Moz_Class(M) {
+        var type = M instanceof AST_ClassExpression ? "ClassExpression" : "ClassDeclaration";
+        return {
+            type: type,
+            superClass: to_moz(M.extends),
+            id: M.name ? to_moz(M.name) : null,
+            body: {
+                type: "ClassBody",
+                body: M.properties.map(to_moz)
+            }
+        }
+    });
+
+    def_to_moz(AST_NewTarget, function To_Moz_MetaProperty(M) {
+        return {
+            type: "MetaProperty",
+            meta: {
+                type: "Identifier",
+                name: "new"
+            },
+            property: {
+                type: "Identifier",
+                name: "target"
+            }
+        };
+    });
+
+    def_to_moz(AST_Symbol, function To_Moz_Identifier(M, parent) {
+        if (M instanceof AST_SymbolMethod && parent.quote) {
+            return {
+                type: "Literal",
+                value: M.name
+            };
+        }
         var def = M.definition();
         return {
             type: "Identifier",
@@ -410,14 +861,15 @@
     });
 
     def_to_moz(AST_RegExp, function To_Moz_RegExpLiteral(M) {
-        var value = M.value;
+        var flags = M.value.toString().match(/[gimuy]*$/)[0];
+        var value = "/" + M.value.raw_source + "/" + flags;
         return {
             type: "Literal",
             value: value,
-            raw: value.toString(),
+            raw: value,
             regex: {
-                pattern: value.source,
-                flags: value.toString().match(/[gimuy]*$/)[0]
+                pattern: M.value.raw_source,
+                flags: flags
             }
         };
     });
@@ -586,13 +1038,30 @@
     };
 
     function def_to_moz(mytype, handler) {
-        mytype.DEFMETHOD("to_mozilla_ast", function() {
-            return set_moz_loc(this, handler(this));
+        mytype.DEFMETHOD("to_mozilla_ast", function(parent) {
+            return set_moz_loc(this, handler(this, parent));
         });
     };
 
+    var TO_MOZ_STACK = null;
+
     function to_moz(node) {
-        return node != null ? node.to_mozilla_ast() : null;
+        if (TO_MOZ_STACK === null) { TO_MOZ_STACK = []; }
+        TO_MOZ_STACK.push(node);
+        var ast = node != null ? node.to_mozilla_ast(TO_MOZ_STACK[TO_MOZ_STACK.length - 2]) : null;
+        TO_MOZ_STACK.pop();
+        if (TO_MOZ_STACK.length === 0) { TO_MOZ_STACK = null; }
+        return ast
+    };
+
+    function to_moz_in_destructuring() {
+        var i = TO_MOZ_STACK.length;
+        while (i--) {
+            if (TO_MOZ_STACK[i] instanceof AST_Destructuring) {
+                return true;
+            }
+        }
+        return false;
     };
 
     function to_moz_block(node) {
diff --git a/lib/output.js b/lib/output.js
index e4987179..9093665e 100644
--- a/lib/output.js
+++ b/lib/output.js
@@ -1455,7 +1455,15 @@ function OutputStream(options) {
             output.space();
             self.module_name.print(output);
         }
-        output.semicolon();
+        if (self.exported_value
+                && !(self.exported_value instanceof AST_Defun ||
+                    self.exported_value instanceof AST_Function ||
+                    self.exported_value instanceof AST_Class)
+            || self.module_name
+            || self.exported_names
+        ) {
+            output.semicolon();
+        }
     });
 
     function parenthesize_for_noin(node, output, noin) {
diff --git a/lib/parse.js b/lib/parse.js
index d8cc9ac4..c44088c8 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -1159,7 +1159,9 @@ function parse($TEXT, options) {
               case "export":
                 if (!is_token(peek(), "punc", "(")) {
                     next();
-                    return export_();
+                    var node = export_();
+                    if (is("punc", ";")) semicolon();
+                    return node;
                 }
             }
         }
@@ -1294,9 +1296,14 @@ function parse($TEXT, options) {
 
         var body = _function_body(is("punc", "{"), false, is_async);
 
+        var end =
+            body instanceof Array && body.length ? body[body.length - 1].end :
+            body instanceof Array ? start :
+                body.end;
+
         return new AST_Arrow({
             start    : start,
-            end      : body.end,
+            end      : end,
             async    : is_async,
             argnames : argnames,
             body     : body
@@ -1709,6 +1716,8 @@ function parse($TEXT, options) {
         }
         // the await expression is parsed as a unary expression in Babel
         return new AST_Await({
+            start: prev(),
+            end: S.token,
             expression : maybe_unary(true),
         });
     }
@@ -1719,6 +1728,7 @@ function parse($TEXT, options) {
             croak("Unexpected yield expression outside generator function",
                 S.prev.line, S.prev.col, S.prev.pos);
         }
+        var start = S.token;
         var star = false;
         var has_expression = true;
 
@@ -1742,8 +1752,10 @@ function parse($TEXT, options) {
         }
 
         return new AST_Yield({
+            start      : start,
             is_star    : star,
-            expression : has_expression ? expression() : null
+            expression : has_expression ? expression() : null,
+            end        : prev()
         });
     }
 
@@ -2478,7 +2490,7 @@ function parse($TEXT, options) {
             next();
             if (is_import && is("name", "as")) {
                 next();  // The "as" word
-                name = as_symbol(AST_SymbolImportForeign);
+                name = as_symbol(is_import ? AST_SymbolImportForeign : AST_SymbolExportForeign);
             }
             names = [map_nameAsterisk(is_import, name)];
         }
@@ -2686,7 +2698,8 @@ function parse($TEXT, options) {
             return subscripts(new AST_PrefixedTemplateString({
                 start: start,
                 prefix: expr,
-                template_string: template_string()
+                template_string: template_string(),
+                end: prev()
             }), allow_calls);
         }
         return expr;
@@ -2699,7 +2712,8 @@ function parse($TEXT, options) {
                 next();
                 args.push(new AST_Expansion({
                     start: prev(),
-                    expression: expression(false)
+                    expression: expression(false),
+                    end: prev()
                 }));
             } else {
                 args.push(expression(false));
diff --git a/package.json b/package.json
index eb8e902d..c35fd034 100644
--- a/package.json
+++ b/package.json
@@ -29,6 +29,7 @@
   },
   "devDependencies": {
     "acorn": "~5.4.1",
+    "escodegen": "^1.9.1",
     "mocha": "~3.5.1",
     "semver": "~5.5.0"
   },
diff --git a/test/compress/export.js b/test/compress/export.js
index 783fa80a..66eed356 100644
--- a/test/compress/export.js
+++ b/test/compress/export.js
@@ -277,7 +277,7 @@ export_default_anonymous_function: {
             foo();
         }
     }
-    expect_exact: "export default function(){foo()};"
+    expect_exact: "export default function(){foo()}"
 }
 
 export_default_arrow: {
@@ -309,7 +309,7 @@ export_default_anonymous_generator: {
             yield foo();
         }
     }
-    expect_exact: "export default function*(){yield foo()};"
+    expect_exact: "export default function*(){yield foo()}"
 }
 
 export_default_anonymous_async_function: {
@@ -326,7 +326,7 @@ export_default_anonymous_async_function: {
             return await foo();
         }
     }
-    expect_exact: "export default async function(){return await foo()};"
+    expect_exact: "export default async function(){return await foo()}"
 }
 
 export_default_async_arrow_function: {
@@ -358,7 +358,7 @@ export_default_named_generator: {
             yield foo();
         }
     }
-    expect_exact: "export default function*gen(){yield foo()};"
+    expect_exact: "export default function*gen(){yield foo()}"
 }
 
 export_default_named_async_function: {
@@ -375,7 +375,7 @@ export_default_named_async_function: {
             return await foo();
         }
     }
-    expect_exact: "export default async function bar(){return await foo()};"
+    expect_exact: "export default async function bar(){return await foo()}"
 }
 
 export_default_anonymous_class: {
@@ -394,7 +394,7 @@ export_default_anonymous_class: {
             }
         };
     }
-    expect_exact: "export default class{constructor(){foo()}};"
+    expect_exact: "export default class{constructor(){foo()}}"
 }
 
 export_default_anonymous_function_not_call: {
@@ -426,7 +426,7 @@ export_default_anonymous_generator_not_call: {
         export default function*(){}(foo);
     }
     // agrees with `acorn` and `babylon 7`
-    expect_exact: "export default function*(){};foo;"
+    expect_exact: "export default function*(){}foo;"
 }
 
 export_default_anonymous_async_function_not_call: {
@@ -442,5 +442,5 @@ export_default_anonymous_async_function_not_call: {
         export default async function(){}(foo);
     }
     // agrees with `acorn` and `babylon 7`
-    expect_exact: "export default async function(){};foo;"
+    expect_exact: "export default async function(){}foo;"
 }
diff --git a/test/compress/harmony.js b/test/compress/harmony.js
index b85214ec..c7f105c0 100644
--- a/test/compress/harmony.js
+++ b/test/compress/harmony.js
@@ -218,7 +218,7 @@ export_statement: {
         export function d() {};
         export class e {};
     }
-    expect_exact: "export default 3;export var a=4;export let b=6;export const c=6;export function d(){};export class e{};"
+    expect_exact: "export default 3;export var a=4;export let b=6;export const c=6;export function d(){}export class e{}"
 }
 
 export_default_object_expression: {
@@ -254,7 +254,7 @@ export_default_anon_function: {
             console.log(1 + 2);
         }
     }
-    expect_exact: "export default function(){console.log(3)};"
+    expect_exact: "export default function(){console.log(3)}"
 }
 
 export_default_anon_class: {
@@ -266,7 +266,7 @@ export_default_anon_class: {
             foo() { console.log(1 + 2); }
         }
     }
-    expect_exact: "export default class{foo(){console.log(3)}};"
+    expect_exact: "export default class{foo(){console.log(3)}}"
 }
 
 export_module_statement: {
@@ -680,7 +680,7 @@ export_default_function_decl: {
         export default function Foo() {};
         export function Far() {};
     }
-    expect_exact: "export default function Foo(){};export function Far(){};"
+    expect_exact: "export default function Foo(){}export function Far(){}"
 }
 
 export_default_class_decl: {
@@ -694,7 +694,7 @@ export_default_class_decl: {
         export default class Car {};
         export class Cab {};
     }
-    expect_exact: "export default class Car{};export class Cab{};"
+    expect_exact: "export default class Car{}export class Cab{}"
 }
 
 object_rest_spread: {
diff --git a/test/compress/issue-2001.js b/test/compress/issue-2001.js
index f2c9504b..4196f6c3 100644
--- a/test/compress/issue-2001.js
+++ b/test/compress/issue-2001.js
@@ -5,9 +5,9 @@ export_func_1: {
         unused: true,
     }
     input: {
-        export function f(){};
+        export function f(){}
     }
-    expect_exact: "export function f(){};"
+    expect_exact: "export function f(){}"
 }
 
 export_func_2: {
@@ -20,7 +20,7 @@ export_func_2: {
     input: {
         export function f(){}(1);
     }
-    expect_exact: "export function f(){};1;"
+    expect_exact: "export function f(){}1;"
 }
 
 export_func_3: {
@@ -33,7 +33,7 @@ export_func_3: {
     input: {
         export function f(){}(1);
     }
-    expect_exact: "export function f(){};"
+    expect_exact: "export function f(){}"
 }
 
 export_default_func_1: {
@@ -43,9 +43,9 @@ export_default_func_1: {
         unused: true,
     }
     input: {
-        export default function f(){};
+        export default function f(){}
     }
-    expect_exact: "export default function f(){};"
+    expect_exact: "export default function f(){}"
 }
 
 export_default_func_2: {
@@ -58,7 +58,7 @@ export_default_func_2: {
     input: {
         export default function f(){}(1);
     }
-    expect_exact: "export default function f(){};1;"
+    expect_exact: "export default function f(){}1;"
 }
 
 export_default_func_3: {
@@ -71,7 +71,7 @@ export_default_func_3: {
     input: {
         export default function f(){}(1);
     }
-    expect_exact: "export default function f(){};"
+    expect_exact: "export default function f(){}"
 }
 
 export_class_1: {
@@ -83,7 +83,7 @@ export_class_1: {
     input: {
         export class C {};
     }
-    expect_exact: "export class C{};"
+    expect_exact: "export class C{}"
 }
 
 export_class_2: {
@@ -96,7 +96,7 @@ export_class_2: {
     input: {
         export class C {}(1);
     }
-    expect_exact: "export class C{};1;"
+    expect_exact: "export class C{}1;"
 }
 
 export_class_3: {
@@ -109,7 +109,7 @@ export_class_3: {
     input: {
         export class C {}(1);
     }
-    expect_exact: "export class C{};"
+    expect_exact: "export class C{}"
 }
 
 export_default_class_1: {
@@ -121,7 +121,7 @@ export_default_class_1: {
     input: {
         export default class C {};
     }
-    expect_exact: "export default class C{};"
+    expect_exact: "export default class C{}"
 }
 
 export_default_class_2: {
@@ -134,7 +134,7 @@ export_default_class_2: {
     input: {
         export default class C {}(1);
     }
-    expect_exact: "export default class C{};1;"
+    expect_exact: "export default class C{}1;"
 }
 
 export_default_class_3: {
@@ -147,7 +147,7 @@ export_default_class_3: {
     input: {
         export default class C {}(1);
     }
-    expect_exact: "export default class C{};"
+    expect_exact: "export default class C{}"
 }
 
 export_mangle_1: {
@@ -159,7 +159,7 @@ export_mangle_1: {
             return one - two;
         };
     }
-    expect_exact: "export function foo(o,n){return o-n};"
+    expect_exact: "export function foo(o,n){return o-n}"
 }
 
 export_mangle_2: {
@@ -171,7 +171,7 @@ export_mangle_2: {
             return one - two;
         };
     }
-    expect_exact: "export default function foo(o,t){return o-t};"
+    expect_exact: "export default function foo(o,t){return o-t}"
 }
 
 export_mangle_3: {
@@ -190,7 +190,7 @@ export_mangle_3: {
             }
         };
     }
-    expect_exact: "export class C{go(r,e){return r-e+r}};"
+    expect_exact: "export class C{go(r,e){return r-e+r}}"
 }
 
 export_mangle_4: {
@@ -209,7 +209,7 @@ export_mangle_4: {
             }
         };
     }
-    expect_exact: "export default class C{go(e,r){return e-r+e}};"
+    expect_exact: "export default class C{go(e,r){return e-r+e}}"
 }
 
 export_mangle_5: {
@@ -276,8 +276,8 @@ export_default_func_ref: {
         unused: true,
     }
     input: {
-        export default function f(){};
+        export default function f(){}
         f();
     }
-    expect_exact: "export default function f(){};f();"
+    expect_exact: "export default function f(){}f();"
 }
diff --git a/test/input/spidermonkey/input.js b/test/input/spidermonkey/input.js
new file mode 100644
index 00000000..e4de54ec
--- /dev/null
+++ b/test/input/spidermonkey/input.js
@@ -0,0 +1,146 @@
+import "mod-name";
+import Foo from "bar";
+import * as Food from "food"
+import { Bar, Baz } from "lel";
+import Bar1, { Foo2 } from "lel";
+import { Bar2 as kex, Baz as food } from "lel";
+
+const x = 0b01;
+let y = 6;
+
+export default x;
+export const z = 4;
+export function fun() {}
+export * from "a.js";
+export {A} from "a.js";
+export {A1, B1} from "a.js";
+export {C};
+
+(a, [b], {c:foo = 3}, ...d) => null;
+() => {};
+
+async function f() { }
+function*gen() {
+    yield 1;
+    yield* 2;
+}
+
+class Class extends Object {
+    constructor(...args) {
+    }
+    foo() {}
+}
+
+x = class {
+    static staticMethod() {}
+    static get foo() {}
+    static set bar(value) {}
+    get x() {}
+    set x(value) {}
+    static() {
+        // "static" can be a method name!
+    }
+    get() {
+        // "get" can be a method name!
+    }
+    async set() {
+        // "set" can be a method name!
+    }
+    *bar() {}
+    static *baz() {}
+    *['constructor']() {}
+    static ['constructor']() {}
+    [a]() {}
+    "%"(){}
+}
+
+y = {
+    get x() {},
+    set x(value) {},
+    bar() {},
+    *bar() {},
+    *['constructor']() {}
+}
+function f () {
+    console.log(new.target);
+}
+console.log([10, ...[], 20, ...[30, 40], 50]["length"]);
+var { w: w1, ...V } = { w: 7, x: 1, y: 2 };
+for (const x of y) {}
+async function f1() { await x; }
+
+``;
+`x`;
+`x${1}`;
+String.raw`\n`;
+
+// arrow.js
+
+var foo = ([]) => "foo";
+var bar = ({}) => "bar";
+var with_default = (foo = "default") => foo;
+var object_with_default = ({foo = "default", bar: baz = "default"}) => foo;
+var array_after_spread = (...[foo]) => foo;
+var array_after_spread = (...{foo}) => foo;
+var computed = ({ [compute()]: x }) => {};
+var array_hole = ([, , ...x] = [1, 2]) => {};
+var object_trailing_elision = ({foo,}) => {};
+var spread_empty_array = (...[]) => "foo";
+var spread_empty_object = (...{}) => "foo";
+
+// async.js
+
+async (x) => await x
+
+// destructuring.js
+
+var [aa, bb] = cc;
+var [aa, [bb, cc]] = dd;
+var [,[,,,,,],,,zz,] = xx; // Trailing comma
+var [,,zzz,,] = xxx; // Trailing comma after hole
+
+var {aa, bb} = {aa:1, bb:2};
+var {aa, bb: {cc, dd}} = {aa:1, bb: {cc:2, dd: 3}};
+
+for (const [x,y] in pairs);
+for (const [a] = 0;;);
+for (const {c} of cees);
+
+// object.js
+
+var a = {
+    get,
+    set: "foo",
+    get bar() {
+        return this.get;
+    },
+    get 5() {
+        return "five";
+    },
+    get 0xf55() {
+        return "f five five";
+    },
+    get "five"() {
+        return 5;
+    },
+    set one(value) {
+        this._one = value;
+    },
+    set 9(value) {
+        this._nine = value;
+    },
+    set 0b1010(value) {
+        this._ten = value;
+    },
+    set "eleven"(value) {
+        this._eleven = value;
+    },
+    *"%"() {
+        return 2;
+    },
+    *["%"]() {
+        return 2;
+    },
+    [a]() {}
+};
+
diff --git a/test/mocha/spidermonkey.js b/test/mocha/spidermonkey.js
index 709b89e5..d9d6f244 100644
--- a/test/mocha/spidermonkey.js
+++ b/test/mocha/spidermonkey.js
@@ -1,5 +1,8 @@
 var assert = require("assert");
+var fs = require("fs");
 var exec = require("child_process").exec;
+var acorn = require("acorn");
+var escodegen = require("escodegen");
 var uglify = require("../node");
 
 describe("spidermonkey export/import sanity test", function() {
@@ -112,4 +115,42 @@ describe("spidermonkey export/import sanity test", function() {
             assert.strictEqual(counter_strings, tests[i].strings, "String count mismatch for test " + tests[i].input);
         }
     });
+
+    it("should output and parse ES6 code correctly", function() {
+        var code = fs.readFileSync("test/input/spidermonkey/input.js", "utf-8");
+        var uglify_ast = uglify.parse(code);
+        var moz_ast = uglify_ast.to_mozilla_ast();
+        var from_moz_ast = uglify.AST_Node.from_mozilla_ast(moz_ast);
+        assert.strictEqual(
+            from_moz_ast.print_to_string(),
+            uglify_ast.print_to_string()
+        );
+    });
+
+    it("should be capable of importing from acorn", function() {
+        var code = fs.readFileSync("test/input/spidermonkey/input.js", "utf-8");
+        var uglify_ast = uglify.parse(code);
+        var moz_ast = acorn.parse(code, {sourceType: 'module', ecmaVersion: 9});
+        var from_moz_ast = uglify.AST_Node.from_mozilla_ast(moz_ast);
+        assert.strictEqual(
+            from_moz_ast.print_to_string(),
+            uglify_ast.print_to_string()
+        );
+    });
+
+    it("should produce an AST compatible with escodegen", function() {
+        var code = fs.readFileSync("test/input/spidermonkey/input.js", "utf-8");
+        var uglify_ast = uglify.parse(code);
+        var moz_ast = uglify_ast.to_mozilla_ast();
+        var generated = escodegen.generate(moz_ast)
+            .replace(/\[object Object\].\[object Object\]/g, "new.target");  // escodegen issue
+        var parsed = acorn.parse(generated, {
+            sourceType: "module",
+            ecmaVersion: 9
+        });
+        assert.strictEqual(
+            uglify.AST_Node.from_mozilla_ast(parsed).print_to_string(),
+            uglify_ast.print_to_string()
+        );
+    });
 });
diff --git a/test/run-tests.js b/test/run-tests.js
index deb1f954..05994d99 100755
--- a/test/run-tests.js
+++ b/test/run-tests.js
@@ -110,6 +110,16 @@ function run_compress_tests() {
                 });
                 return false;
             }
+            var ast = input.to_mozilla_ast();
+            var ast_as_string = U.AST_Node.from_mozilla_ast(ast).print_to_string();
+            var input_string = input.print_to_string();
+            if (input_string !== ast_as_string) {
+                log("!!! Mozilla AST I/O corrupted input\n---INPUT---\n{input}\n---OUTPUT---\n{output}\n\n", {
+                    input: input_string,
+                    output: ast_as_string,
+                });
+                return false;
+            }
             var options = U.defaults(test.options, {
                 warnings: false
             });