[CS1] Backport #4783, fix for export default followed by an implicit object

src/grammar.coffee

@@ -396,6 +396,7 @@ grammar =
     o 'EXPORT Identifier = INDENT Expression OUTDENT',       -> new ExportNamedDeclaration new Assign $2, $5, null,
                                                                                                       moduleDeclaration: 'export'
     o 'EXPORT DEFAULT Expression',                           -> new ExportDefaultDeclaration $3
+    o 'EXPORT DEFAULT INDENT Object OUTDENT',                -> new ExportDefaultDeclaration new Value $4
     o 'EXPORT EXPORT_ALL FROM String',                       -> new ExportAllDeclaration new Literal($2), $4
     o 'EXPORT { ExportSpecifierList OptComma } FROM String', -> new ExportNamedDeclaration new ExportSpecifierList($3), $7
   ]

src/lexer.coffee

@@ -1096,4 +1096,4 @@ INDENTABLE_CLOSERS = [')', '}', ']']
 # Tokens that, when appearing at the end of a line, suppress a following TERMINATOR/INDENT token
 UNFINISHED = ['\\', '.', '?.', '?::', 'UNARY', 'MATH', 'UNARY_MATH', '+', '-',
            '**', 'SHIFT', 'RELATION', 'COMPARE', '&', '^', '|', '&&', '||',
-           'BIN?', 'THROW', 'EXTENDS', 'DEFAULT']
+           'BIN?', 'THROW', 'EXTENDS']

test/modules.coffee

@@ -359,7 +359,7 @@ test "export default implicit object", ->
 test "export default multiline implicit object", ->
   input = """
     export default
-      foo: 'bar',
+      foo: 'bar'
       baz: 'qux'
     """
   output = """
@@ -369,6 +369,25 @@ test "export default multiline implicit object", ->
     };"""
   eq toJS(input), output
 
+test "export default multiline implicit object with internal braces", ->
+  input = """
+    export default
+      foo: yes
+      bar: {
+        baz
+      }
+      quz: no
+    """
+  output = """
+    export default {
+      foo: true,
+      bar: {
+        baz: baz
+      },
+      quz: false
+    };"""
+  eq toJS(input), output
+
 test "export default assignment expression", ->
   input = "export default foo = 'bar'"
   output = """