pub global activate l10n fails

[test_l10n]$ pub global activate l10n
Package l10n is currently active at version 2.0.15.
Resolving dependencies... (4.2s)
+ analyzer 0.32.6 (0.34.2 available)
+ ansicolor 1.0.2
+ args 1.5.1
+ async 2.0.8
+ build_cli_annotations 1.0.1
+ charcode 1.1.2
+ collection 1.14.11
+ console_log_handler 1.1.6
+ convert 2.1.1
+ crypto 2.0.6
+ csslib 0.14.6
+ dart_style 1.1.3 (1.2.2 available)
+ front_end 0.1.4+2 (0.1.9 available)
+ glob 1.1.7
+ html 0.13.3+3
+ intl 0.15.7
+ intl_translation 0.17.1 (0.17.2 available)
+ kernel 0.3.4+2 (0.3.9 available)
+ l10n 2.0.15
+ logging 0.11.3+2
+ matcher 0.12.4
+ meta 1.1.7
+ optional 3.0.0+2
+ package_config 1.0.5
+ path 1.6.2
+ petitparser 1.7.7 (2.1.1 available)
+ plugin 0.2.0+3
+ source_span 1.5.3
+ stack_trace 1.9.3
+ string_scanner 1.0.4
+ term_glyph 1.1.0
+ typed_data 1.1.6
+ utf 0.9.0+5
+ validate 1.7.0
+ watcher 0.9.7+10
+ where 4.4.0 (6.1.0 available)
+ yaml 2.1.15
Precompiling executables... (5.3s)
Failed to precompile l10n:mkl10n:
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:50:5: Error: 'Future' expects 0 type arguments.
    Future<String> findLocale(),
    ^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:51:5: Error: 'Future' expects 0 type arguments.
    Future<bool> initMessages(final String locale)) async {
    ^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:49:1: Error: 'Future' expects 0 type arguments.
Future<String> initLanguageSettings(
^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:50:5: Error: 'Future' isn't a type.
    Future<String> findLocale(),
    ^^^^^^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:51:5: Error: 'Future' isn't a type.
    Future<bool> initMessages(final String locale)) async {
    ^^^^^^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:54:27: Error: A value of type 'invalid-type' can't be assigned to a variable of type 'dart.core::String'.
Try changing the type of the left hand side, or casting the right hand side to 'dart.core::String'.
    final String locale = await findLocale(); // Calls platform specific "findSystemLocale"
                          ^
file:///Users/XXX/.pub-cache/hosted/pub.dartlang.org/l10n-2.0.15/lib/l10n.dart:69:12: Error: A value of type 'dart.core::String' can't be assigned to a variable of type 'dart.async::FutureOr<invalid-type>'.
Try changing the type of the left hand side, or casting the right hand side to 'dart.async::FutureOr<invalid-type>'.
    return shortLocale;
           ^

flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel master, v1.1.10-pre.160, on Mac OS X 10.14.1 18B75, locale fr-FR)
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] iOS toolchain - develop for iOS devices (Xcode 10.0)
[✓] Android Studio (version 3.2)
[✓] IntelliJ IDEA Ultimate Edition (version 2018.2.5)
[✓] VS Code (version 1.30.2)
[!] Connected device
    ! No devices available

MikeMitterer / dart-l10n-gettext

pub global activate l10n fails #3