Update dependencies, support nightlies, target 3.27

Author: fredemmott

.hhconfig

@@ -1,11 +1,13 @@
 assume_php=false
-enable_experimental_tc_features = no_fallback_in_namespaces, unpacking_check_arity, disallow_refs_in_array, disallow_untyped_lambda_as_non_function_type
-safe_array = true
-safe_vector_array = true
-disallow_destruct = true
+
+disallow_elvis_space=true
+disallow_non_arraykey_keys=true
+disallow_unsafe_comparisons=true
+decl_override_require_hint=true
+enable_experimental_tc_features=shape_field_check,sealed_classes
 
 # ignore HHAST as:
 # - otherwise, we get a circular dependency
 # - we don't use anything other than executables from it
 ignored_paths = [ "vendor/.+/tests/.+", "vendor/hhvm/hhast/.+" ]
-forward_compatibility_level=3.27
+forward_compatibility_level=20180704

.travis.yml

@@ -1,7 +1,7 @@
 language: php
 php:
  - hhvm
- - hhvm-3.24
+ - hhvm-3.27
  - hhvm-nightly
 script:
  - ./.travis.sh

composer.json

@@ -3,7 +3,7 @@
     "description": "Hack Codegen is a library for programatically generating Hack code",
     "keywords": ["code generation", "Hack"],
     "require": {
-        "hhvm": ">=3.23.0",
+        "hhvm": ">=3.27.0",
         "hhvm/hhvm-autoload": "^1.5",
         "hhvm/hsl": "^1.0.0|^3.26.0"
     },
@@ -36,6 +36,6 @@
         "91carriage/phpunit-hhi": "^5.6",
         "hhvm/type-assert": "^3.1",
         "facebook/fbexpect": "^0.4.0|^1.0.0",
-        "hhvm/hhast": "^0.4.0|^1.0.0"
+        "hhvm/hhast": "^3.26.0"
     }
 }