Merge pull request #423 from ueokande/greenkeeper/eslint-5.0.1

Update eslint

24 files changed, 489 insertions, 157 deletions

diff --git a/.eslintrc b/.eslintrc
index 0f230c7..e919f28 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -29,6 +29,7 @@
     "id-length": "off",
     "indent": ["error", 2],
     "jsx-quotes": ["error", "prefer-single"],
+    "max-classes-per-file": "off",
     "max-params": ["error", 5],
     "max-statements": ["error", 15],
     "multiline-comment-style": "off",
diff --git a/e2e/ambassador/src/client/keys.js b/e2e/ambassador/src/client/keys.js
index 37b9c0a..6b36c23 100644
--- a/e2e/ambassador/src/client/keys.js
+++ b/e2e/ambassador/src/client/keys.js
@@ -4,28 +4,25 @@ import * as ipc from './ipc';
 const NEUTRAL_MODIFIERS = { shiftKey: false, altKey: false, ctrlKey: false };
 
 const press = (tabId, key, modifiers = NEUTRAL_MODIFIERS) => {
-  return ipc.send(Object.assign({}, modifiers, {
+  return ipc.send({ ...modifiers,
     type: EVENT_KEYPRESS,
     tabId,
-    key,
-  }));
+    key, });
 };
 
 const down = (tabId, key, modifiers = NEUTRAL_MODIFIERS) => {
-  return ipc.send(Object.assign({}, modifiers, {
+  return ipc.send({ modifiers,
     type: EVENT_KEYDOWN,
     tabId,
-    key,
-  }));
+    key, });
 };
 
 
 const up = (tabId, key, modifiers = NEUTRAL_MODIFIERS) => {
-  return ipc.send(Object.assign({}, modifiers, {
+  return ipc.send({ modifiers,
     type: EVENT_KEYUP,
     tabId,
-    key,
-  }));
+    key, });
 };
 
 export { press, down, up };
diff --git a/package-lock.json b/package-lock.json
index e28de11..7c59307 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1436,6 +1436,28 @@
         "trim-right": "^1.0.1"
       }
     },
+    "babel-helper-bindify-decorators": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-bindify-decorators/-/babel-helper-bindify-decorators-6.24.1.tgz",
+      "integrity": "sha1-FMGeXxQte0fxmlJDHlKxzLxAozA=",
+      "dev": true,
+      "requires": {
+        "babel-runtime": "^6.22.0",
+        "babel-traverse": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-helper-builder-binary-assignment-operator-visitor": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-builder-binary-assignment-operator-visitor/-/babel-helper-builder-binary-assignment-operator-visitor-6.24.1.tgz",
+      "integrity": "sha1-zORReto1b0IgvK6KAsKzRvmlZmQ=",
+      "dev": true,
+      "requires": {
+        "babel-helper-explode-assignable-expression": "^6.24.1",
+        "babel-runtime": "^6.22.0",
+        "babel-types": "^6.24.1"
+      }
+    },
     "babel-helper-builder-react-jsx": {
       "version": "6.26.0",
       "resolved": "https://registry.npmjs.org/babel-helper-builder-react-jsx/-/babel-helper-builder-react-jsx-6.26.0.tgz",
@@ -1447,6 +1469,65 @@
         "esutils": "^2.0.2"
       }
     },
+    "babel-helper-explode-assignable-expression": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-explode-assignable-expression/-/babel-helper-explode-assignable-expression-6.24.1.tgz",
+      "integrity": "sha1-8luCz33BBDPFX3BZLVdGQArCLKo=",
+      "dev": true,
+      "requires": {
+        "babel-runtime": "^6.22.0",
+        "babel-traverse": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-helper-explode-class": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-explode-class/-/babel-helper-explode-class-6.24.1.tgz",
+      "integrity": "sha1-fcKjkQ3uAHBW4eMdZAztPVTqqes=",
+      "dev": true,
+      "requires": {
+        "babel-helper-bindify-decorators": "^6.24.1",
+        "babel-runtime": "^6.22.0",
+        "babel-traverse": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-helper-function-name": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-function-name/-/babel-helper-function-name-6.24.1.tgz",
+      "integrity": "sha1-00dbjAPtmCQqJbSDUasYOZ01gKk=",
+      "dev": true,
+      "requires": {
+        "babel-helper-get-function-arity": "^6.24.1",
+        "babel-runtime": "^6.22.0",
+        "babel-template": "^6.24.1",
+        "babel-traverse": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-helper-get-function-arity": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-get-function-arity/-/babel-helper-get-function-arity-6.24.1.tgz",
+      "integrity": "sha1-j3eCqpNAfEHTqlCQj4mwMbG2hT0=",
+      "dev": true,
+      "requires": {
+        "babel-runtime": "^6.22.0",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-helper-remap-async-to-generator": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-helper-remap-async-to-generator/-/babel-helper-remap-async-to-generator-6.24.1.tgz",
+      "integrity": "sha1-XsWBgnrXI/7N04HxySg5BnbkVRs=",
+      "dev": true,
+      "requires": {
+        "babel-helper-function-name": "^6.24.1",
+        "babel-runtime": "^6.22.0",
+        "babel-template": "^6.24.1",
+        "babel-traverse": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
     "babel-helpers": {
       "version": "6.24.1",
       "resolved": "https://registry.npmjs.org/babel-helpers/-/babel-helpers-6.24.1.tgz",
@@ -1477,12 +1558,128 @@
         "babel-runtime": "^6.22.0"
       }
     },
+    "babel-plugin-syntax-async-functions": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-async-functions/-/babel-plugin-syntax-async-functions-6.13.0.tgz",
+      "integrity": "sha1-ytnK0RkbWtY0vzCuCHI5HgZHvpU=",
+      "dev": true
+    },
+    "babel-plugin-syntax-async-generators": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-async-generators/-/babel-plugin-syntax-async-generators-6.13.0.tgz",
+      "integrity": "sha1-a8lj67FuzLrmuStZbrfzXDQqi5o=",
+      "dev": true
+    },
+    "babel-plugin-syntax-class-properties": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-class-properties/-/babel-plugin-syntax-class-properties-6.13.0.tgz",
+      "integrity": "sha1-1+sjt5oxf4VDlixQW4J8fWysJ94=",
+      "dev": true
+    },
+    "babel-plugin-syntax-decorators": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-decorators/-/babel-plugin-syntax-decorators-6.13.0.tgz",
+      "integrity": "sha1-MSVjtNvePMgGzuPkFszurd0RrAs=",
+      "dev": true
+    },
+    "babel-plugin-syntax-dynamic-import": {
+      "version": "6.18.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-dynamic-import/-/babel-plugin-syntax-dynamic-import-6.18.0.tgz",
+      "integrity": "sha1-jWomIpyDdFqZgqRBBRVyyqF5sdo=",
+      "dev": true
+    },
+    "babel-plugin-syntax-exponentiation-operator": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-exponentiation-operator/-/babel-plugin-syntax-exponentiation-operator-6.13.0.tgz",
+      "integrity": "sha1-nufoM3KQ2pUoggGmpX9BcDF4MN4=",
+      "dev": true
+    },
     "babel-plugin-syntax-jsx": {
       "version": "6.18.0",
       "resolved": "https://registry.npmjs.org/babel-plugin-syntax-jsx/-/babel-plugin-syntax-jsx-6.18.0.tgz",
       "integrity": "sha1-CvMqmm4Tyno/1QaeYtew9Y0NiUY=",
       "dev": true
     },
+    "babel-plugin-syntax-object-rest-spread": {
+      "version": "6.13.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-object-rest-spread/-/babel-plugin-syntax-object-rest-spread-6.13.0.tgz",
+      "integrity": "sha1-/WU28rzhODb/o6VFjEkDpZe7O/U=",
+      "dev": true
+    },
+    "babel-plugin-syntax-trailing-function-commas": {
+      "version": "6.22.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-syntax-trailing-function-commas/-/babel-plugin-syntax-trailing-function-commas-6.22.0.tgz",
+      "integrity": "sha1-ugNgk3+NBuQBgKQ/4NVhb/9TLPM=",
+      "dev": true
+    },
+    "babel-plugin-transform-async-generator-functions": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-async-generator-functions/-/babel-plugin-transform-async-generator-functions-6.24.1.tgz",
+      "integrity": "sha1-8FiQAUX9PpkHpt3yjaWfIVJYpds=",
+      "dev": true,
+      "requires": {
+        "babel-helper-remap-async-to-generator": "^6.24.1",
+        "babel-plugin-syntax-async-generators": "^6.5.0",
+        "babel-runtime": "^6.22.0"
+      }
+    },
+    "babel-plugin-transform-async-to-generator": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-async-to-generator/-/babel-plugin-transform-async-to-generator-6.24.1.tgz",
+      "integrity": "sha1-ZTbjeK/2yx1VF6wOQOs+n8jQh2E=",
+      "dev": true,
+      "requires": {
+        "babel-helper-remap-async-to-generator": "^6.24.1",
+        "babel-plugin-syntax-async-functions": "^6.8.0",
+        "babel-runtime": "^6.22.0"
+      }
+    },
+    "babel-plugin-transform-class-properties": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-class-properties/-/babel-plugin-transform-class-properties-6.24.1.tgz",
+      "integrity": "sha1-anl2PqYdM9NvN7YRqp3vgagbRqw=",
+      "dev": true,
+      "requires": {
+        "babel-helper-function-name": "^6.24.1",
+        "babel-plugin-syntax-class-properties": "^6.8.0",
+        "babel-runtime": "^6.22.0",
+        "babel-template": "^6.24.1"
+      }
+    },
+    "babel-plugin-transform-decorators": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-decorators/-/babel-plugin-transform-decorators-6.24.1.tgz",
+      "integrity": "sha1-eIAT2PjGtSIr33s0Q5Df13Vp4k0=",
+      "dev": true,
+      "requires": {
+        "babel-helper-explode-class": "^6.24.1",
+        "babel-plugin-syntax-decorators": "^6.13.0",
+        "babel-runtime": "^6.22.0",
+        "babel-template": "^6.24.1",
+        "babel-types": "^6.24.1"
+      }
+    },
+    "babel-plugin-transform-exponentiation-operator": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-exponentiation-operator/-/babel-plugin-transform-exponentiation-operator-6.24.1.tgz",
+      "integrity": "sha1-KrDJx/MJj6SJB3cruBP+QejeOg4=",
+      "dev": true,
+      "requires": {
+        "babel-helper-builder-binary-assignment-operator-visitor": "^6.24.1",
+        "babel-plugin-syntax-exponentiation-operator": "^6.8.0",
+        "babel-runtime": "^6.22.0"
+      }
+    },
+    "babel-plugin-transform-object-rest-spread": {
+      "version": "6.26.0",
+      "resolved": "https://registry.npmjs.org/babel-plugin-transform-object-rest-spread/-/babel-plugin-transform-object-rest-spread-6.26.0.tgz",
+      "integrity": "sha1-DzZpLVD+9rfi1LOsFHgTepY7ewY=",
+      "dev": true,
+      "requires": {
+        "babel-plugin-syntax-object-rest-spread": "^6.8.0",
+        "babel-runtime": "^6.26.0"
+      }
+    },
     "babel-plugin-transform-react-jsx": {
       "version": "6.24.1",
       "resolved": "https://registry.npmjs.org/babel-plugin-transform-react-jsx/-/babel-plugin-transform-react-jsx-6.24.1.tgz",
@@ -1523,6 +1720,31 @@
         "babel-plugin-transform-react-jsx": "^6.0.2"
       }
     },
+    "babel-preset-stage-2": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-preset-stage-2/-/babel-preset-stage-2-6.24.1.tgz",
+      "integrity": "sha1-2eKWD7PXEYfw5k7sYrwHdnIZvcE=",
+      "dev": true,
+      "requires": {
+        "babel-plugin-syntax-dynamic-import": "^6.18.0",
+        "babel-plugin-transform-class-properties": "^6.24.1",
+        "babel-plugin-transform-decorators": "^6.24.1",
+        "babel-preset-stage-3": "^6.24.1"
+      }
+    },
+    "babel-preset-stage-3": {
+      "version": "6.24.1",
+      "resolved": "https://registry.npmjs.org/babel-preset-stage-3/-/babel-preset-stage-3-6.24.1.tgz",
+      "integrity": "sha1-g2raCp56f6N8sTj7kyb4eTSkg5U=",
+      "dev": true,
+      "requires": {
+        "babel-plugin-syntax-trailing-function-commas": "^6.22.0",
+        "babel-plugin-transform-async-generator-functions": "^6.24.1",
+        "babel-plugin-transform-async-to-generator": "^6.24.1",
+        "babel-plugin-transform-exponentiation-operator": "^6.24.1",
+        "babel-plugin-transform-object-rest-spread": "^6.22.0"
+      }
+    },
     "babel-register": {
       "version": "6.26.0",
       "resolved": "https://registry.npmjs.org/babel-register/-/babel-register-6.26.0.tgz",
@@ -4097,51 +4319,84 @@
       }
     },
     "eslint": {
-      "version": "4.19.1",
-      "resolved": "https://registry.npmjs.org/eslint/-/eslint-4.19.1.tgz",
-      "integrity": "sha512-bT3/1x1EbZB7phzYu7vCr1v3ONuzDtX8WjuM9c0iYxe+cq+pwcKEoQjl7zd3RpC6YOLgnSy3cTN58M2jcoPDIQ==",
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/eslint/-/eslint-5.0.1.tgz",
+      "integrity": "sha512-D5nG2rErquLUstgUaxJlWB5+gu+U/3VDY0fk/Iuq8y9CUFy/7Y6oF4N2cR1tV8knzQvciIbfqfohd359xTLIKQ==",
       "dev": true,
       "requires": {
-        "ajv": "^5.3.0",
-        "babel-code-frame": "^6.22.0",
+        "ajv": "^6.5.0",
+        "babel-code-frame": "^6.26.0",
         "chalk": "^2.1.0",
-        "concat-stream": "^1.6.0",
-        "cross-spawn": "^5.1.0",
+        "cross-spawn": "^6.0.5",
         "debug": "^3.1.0",
         "doctrine": "^2.1.0",
-        "eslint-scope": "^3.7.1",
+        "eslint-scope": "^4.0.0",
         "eslint-visitor-keys": "^1.0.0",
-        "espree": "^3.5.4",
-        "esquery": "^1.0.0",
+        "espree": "^4.0.0",
+        "esquery": "^1.0.1",
         "esutils": "^2.0.2",
         "file-entry-cache": "^2.0.0",
         "functional-red-black-tree": "^1.0.1",
         "glob": "^7.1.2",
-        "globals": "^11.0.1",
+        "globals": "^11.5.0",
         "ignore": "^3.3.3",
         "imurmurhash": "^0.1.4",
-        "inquirer": "^3.0.6",
-        "is-resolvable": "^1.0.0",
-        "js-yaml": "^3.9.1",
+        "inquirer": "^5.2.0",
+        "is-resolvable": "^1.1.0",
+        "js-yaml": "^3.11.0",
         "json-stable-stringify-without-jsonify": "^1.0.1",
         "levn": "^0.3.0",
-        "lodash": "^4.17.4",
-        "minimatch": "^3.0.2",
+        "lodash": "^4.17.5",
+        "minimatch": "^3.0.4",
         "mkdirp": "^0.5.1",
         "natural-compare": "^1.4.0",
         "optionator": "^0.8.2",
         "path-is-inside": "^1.0.2",
         "pluralize": "^7.0.0",
         "progress": "^2.0.0",
-        "regexpp": "^1.0.1",
+        "regexpp": "^1.1.0",
         "require-uncached": "^1.0.3",
-        "semver": "^5.3.0",
+        "semver": "^5.5.0",
+        "string.prototype.matchall": "^2.0.0",
         "strip-ansi": "^4.0.0",
-        "strip-json-comments": "~2.0.1",
-        "table": "4.0.2",
-        "text-table": "~0.2.0"
+        "strip-json-comments": "^2.0.1",
+        "table": "^4.0.3",
+        "text-table": "^0.2.0"
       },
       "dependencies": {
+        "acorn": {
+          "version": "5.7.1",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.1.tgz",
+          "integrity": "sha512-d+nbxBUGKg7Arpsvbnlq61mc12ek3EY8EQldM3GPAhWJ1UVxC6TDGbIvUMNU6obBX3i1+ptCIzV4vq0gFPEGVQ==",
+          "dev": true
+        },
+        "acorn-jsx": {
+          "version": "4.1.1",
+          "resolved": "https://registry.npmjs.org/acorn-jsx/-/acorn-jsx-4.1.1.tgz",
+          "integrity": "sha512-JY+iV6r+cO21KtntVvFkD+iqjtdpRUpGqKWgfkCdZq1R+kbreEl8EcdcJR4SmiIgsIQT33s6QzheQ9a275Q8xw==",
+          "dev": true,
+          "requires": {
+            "acorn": "^5.0.3"
+          }
+        },
+        "ajv": {
+          "version": "6.5.1",
+          "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.5.1.tgz",
+          "integrity": "sha512-pgZos1vgOHDiC7gKNbZW8eKvCnNXARv2oqrGQT7Hzbq5Azp7aZG6DJzADnkuSq7RH6qkXp4J/m68yPX/2uBHyQ==",
+          "dev": true,
+          "requires": {
+            "fast-deep-equal": "^2.0.1",
+            "fast-json-stable-stringify": "^2.0.0",
+            "json-schema-traverse": "^0.4.1",
+            "uri-js": "^4.2.1"
+          }
+        },
+        "ajv-keywords": {
+          "version": "3.2.0",
+          "resolved": "https://registry.npmjs.org/ajv-keywords/-/ajv-keywords-3.2.0.tgz",
+          "integrity": "sha1-6GuBnGAs+IIa1jdBNpjx3sAhhHo=",
+          "dev": true
+        },
         "ansi-regex": {
           "version": "3.0.0",
           "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-3.0.0.tgz",
@@ -4168,6 +4423,19 @@
             "supports-color": "^5.3.0"
           }
         },
+        "cross-spawn": {
+          "version": "6.0.5",
+          "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-6.0.5.tgz",
+          "integrity": "sha512-eTVLrBSt7fjbDygz805pMnstIs2VTBNkRm0qxZd+M7A5XDdxVRWO5MxGBXZhjY4cqLYLdtrGqRf8mBPmzwSpWQ==",
+          "dev": true,
+          "requires": {
+            "nice-try": "^1.0.4",
+            "path-key": "^2.0.1",
+            "semver": "^5.5.0",
+            "shebang-command": "^1.2.0",
+            "which": "^1.2.9"
+          }
+        },
         "debug": {
           "version": "3.1.0",
           "resolved": "https://registry.npmjs.org/debug/-/debug-3.1.0.tgz",
@@ -4177,28 +4445,90 @@
             "ms": "2.0.0"
           }
         },
+        "eslint-scope": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/eslint-scope/-/eslint-scope-4.0.0.tgz",
+          "integrity": "sha512-1G6UTDi7Jc1ELFwnR58HV4fK9OQK4S6N985f166xqXxpjU6plxFISJa2Ba9KCQuFa8RCnj/lSFJbHo7UFDBnUA==",
+          "dev": true,
+          "requires": {
+            "esrecurse": "^4.1.0",
+            "estraverse": "^4.1.1"
+          }
+        },
+        "espree": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/espree/-/espree-4.0.0.tgz",
+          "integrity": "sha512-kapdTCt1bjmspxStVKX6huolXVV5ZfyZguY1lcfhVVZstce3bqxH9mcLzNn3/mlgW6wQ732+0fuG9v7h0ZQoKg==",
+          "dev": true,
+          "requires": {
+            "acorn": "^5.6.0",
+            "acorn-jsx": "^4.1.1"
+          }
+        },
         "esprima": {
           "version": "4.0.0",
           "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.0.tgz",
           "integrity": "sha512-oftTcaMu/EGrEIu904mWteKIv8vMuOgGYo7EhVJJN00R/EED9DCua/xxHRdYnKtcECzVg7xOWhflvJMnqcFZjw==",
           "dev": true
         },
+        "fast-deep-equal": {
+          "version": "2.0.1",
+          "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-2.0.1.tgz",
+          "integrity": "sha1-ewUhjd+WZ79/Nwv3/bLLFf3Qqkk=",
+          "dev": true
+        },
         "globals": {
-          "version": "11.5.0",
-          "resolved": "https://registry.npmjs.org/globals/-/globals-11.5.0.tgz",
-          "integrity": "sha512-hYyf+kI8dm3nORsiiXUQigOU62hDLfJ9G01uyGMxhc6BKsircrUhC4uJPQPUSuq2GrTmiiEt7ewxlMdBewfmKQ==",
+          "version": "11.7.0",
+          "resolved": "https://registry.npmjs.org/globals/-/globals-11.7.0.tgz",
+          "integrity": "sha512-K8BNSPySfeShBQXsahYB/AbbWruVOTyVpgoIDnl8odPpeSfP2J5QO2oLFFdl2j7GfDCtZj2bMKar2T49itTPCg==",
           "dev": true
         },
+        "inquirer": {
+          "version": "5.2.0",
+          "resolved": "https://registry.npmjs.org/inquirer/-/inquirer-5.2.0.tgz",
+          "integrity": "sha512-E9BmnJbAKLPGonz0HeWHtbKf+EeSP93paWO3ZYoUpq/aowXvYGjjCSuashhXPpzbArIjBbji39THkxTz9ZeEUQ==",
+          "dev": true,
+          "requires": {
+            "ansi-escapes": "^3.0.0",
+            "chalk": "^2.0.0",
+            "cli-cursor": "^2.1.0",
+            "cli-width": "^2.0.0",
+            "external-editor": "^2.1.0",
+            "figures": "^2.0.0",
+            "lodash": "^4.3.0",
+            "mute-stream": "0.0.7",
+            "run-async": "^2.2.0",
+            "rxjs": "^5.5.2",
+            "string-width": "^2.1.0",
+            "strip-ansi": "^4.0.0",
+            "through": "^2.3.6"
+          }
+        },
         "js-yaml": {
-          "version": "3.11.0",
-          "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.11.0.tgz",
-          "integrity": "sha512-saJstZWv7oNeOyBh3+Dx1qWzhW0+e6/8eDzo7p5rDFqxntSztloLtuKu+Ejhtq82jsilwOIZYsCz+lIjthg1Hw==",
+          "version": "3.12.0",
+          "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.12.0.tgz",
+          "integrity": "sha512-PIt2cnwmPfL4hKNwqeiuz4bKfnzHTBv6HyVgjahA6mPLwPDzjDWrplJBMjHUFxku/N3FlmrbyPclad+I+4mJ3A==",
           "dev": true,
           "requires": {
             "argparse": "^1.0.7",
             "esprima": "^4.0.0"
           }
         },
+        "json-schema-traverse": {
+          "version": "0.4.1",
+          "resolved": "https://registry.npmjs.org/json-schema-traverse/-/json-schema-traverse-0.4.1.tgz",
+          "integrity": "sha512-xbbCH5dCYU5T8LcEhhuh7HJ88HXuW3qsI3Y0zOZFKfZEHcpWiHU/Jxzk629Brsab/mMiHQti9wMP+845RPe3Vg==",
+          "dev": true
+        },
+        "rxjs": {
+          "version": "5.5.11",
+          "resolved": "https://registry.npmjs.org/rxjs/-/rxjs-5.5.11.tgz",
+          "integrity": "sha512-3bjO7UwWfA2CV7lmwYMBzj4fQ6Cq+ftHc2MvUe+WMS7wcdJ1LosDWmdjPQanYp2dBRj572p7PeU81JUxHKOcBA==",
+          "dev": true,
+          "requires": {
+            "symbol-observable": "1.0.1"
+          }
+        },
         "strip-ansi": {
           "version": "4.0.0",
           "resolved": "https://registry.npmjs.org/strip-ansi/-/strip-ansi-4.0.0.tgz",
@@ -4216,6 +4546,20 @@
           "requires": {
             "has-flag": "^3.0.0"
           }
+        },
+        "table": {
+          "version": "4.0.3",
+          "resolved": "https://registry.npmjs.org/table/-/table-4.0.3.tgz",
+          "integrity": "sha512-S7rnFITmBH1EnyKcvxBh1LjYeQMmnZtCXSEbHcH6S0NoKit24ZuFO/T1vDcLdYsLQkM188PVVhQmzKIuThNkKg==",
+          "dev": true,
+          "requires": {
+            "ajv": "^6.0.1",
+            "ajv-keywords": "^3.0.0",
+            "chalk": "^2.1.0",
+            "lodash": "^4.17.4",
+            "slice-ansi": "1.0.0",
+            "string-width": "^2.1.1"
+          }
         }
       }
     },
@@ -5167,14 +5511,12 @@
         "balanced-match": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "balanced-match": "^1.0.0",
             "concat-map": "0.0.1"
@@ -5189,20 +5531,17 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -5319,8 +5658,7 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "ini": {
           "version": "1.3.5",
@@ -5332,7 +5670,6 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -5347,7 +5684,6 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
@@ -5355,14 +5691,12 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "minipass": {
           "version": "2.2.4",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.1",
             "yallist": "^3.0.0"
@@ -5381,7 +5715,6 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -5462,8 +5795,7 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "object-assign": {
           "version": "4.1.1",
@@ -5475,7 +5807,6 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -5597,7 +5928,6 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
@@ -11119,6 +11449,15 @@
         "safe-regex": "^1.1.0"
       }
     },
+    "regexp.prototype.flags": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/regexp.prototype.flags/-/regexp.prototype.flags-1.2.0.tgz",
+      "integrity": "sha512-ztaw4M1VqgMwl9HlPpOuiYgItcHlunW0He2fE6eNfT6E/CF2FtYi9ofOYe4mKntstYk0Fyh/rDRBdS3AnxjlrA==",
+      "dev": true,
+      "requires": {
+        "define-properties": "^1.1.2"
+      }
+    },
     "regexpp": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/regexpp/-/regexpp-1.1.0.tgz",
@@ -12943,6 +13282,19 @@
         }
       }
     },
+    "string.prototype.matchall": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/string.prototype.matchall/-/string.prototype.matchall-2.0.0.tgz",
+      "integrity": "sha512-WoZ+B2ypng1dp4iFLF2kmZlwwlE19gmjgKuhL1FJfDgCREWb3ye3SDVHSzLH6bxfnvYmkCxbzkmWcQZHA4P//Q==",
+      "dev": true,
+      "requires": {
+        "define-properties": "^1.1.2",
+        "es-abstract": "^1.10.0",
+        "function-bind": "^1.1.1",
+        "has-symbols": "^1.0.0",
+        "regexp.prototype.flags": "^1.2.0"
+      }
+    },
     "string_decoder": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
@@ -13068,6 +13420,12 @@
         "whet.extend": "~0.9.9"
       }
     },
+    "symbol-observable": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/symbol-observable/-/symbol-observable-1.0.1.tgz",
+      "integrity": "sha1-g0D8RwLDEi310iKI+IKD9RPT/dQ=",
+      "dev": true
+    },
     "table": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/table/-/table-4.0.2.tgz",
diff --git a/package.json b/package.json
index d6e202c..cf0d241 100644
--- a/package.json
+++ b/package.json
@@ -26,9 +26,10 @@
     "babel-eslint": "^8.2.3",
     "babel-loader": "^7.1.4",
     "babel-preset-preact": "^1.1.0",
+    "babel-preset-stage-2": "^6.24.1",
     "chai": "^4.1.2",
     "css-loader": "^0.28.11",
-    "eslint": "^4.19.1",
+    "eslint": "^5.0.1",
     "eslint-plugin-react": "^7.8.2",
     "html-webpack-plugin": "^3.2.0",
     "karma": "^2.0.2",
diff --git a/src/background/components/operation.js b/src/background/components/operation.js
index 58edb8c..465baf0 100644
--- a/src/background/components/operation.js
+++ b/src/background/components/operation.js
@@ -28,7 +28,7 @@ export default class BackgroundComponent {
     }
   }
 
-  // eslint-disable-next-line complexity
+  // eslint-disable-next-line complexity, max-lines-per-function
   exec(operation, tab) {
     let tabState = this.store.getState().tab;
 
diff --git a/src/background/reducers/find.js b/src/background/reducers/find.js
index 4ded801..bbc6b36 100644
--- a/src/background/reducers/find.js
+++ b/src/background/reducers/find.js
@@ -7,9 +7,8 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.FIND_SET_KEYWORD:
-    return Object.assign({}, state, {
-      keyword: action.keyword,
-    });
+    return { ...state,
+      keyword: action.keyword, };
   default:
     return state;
   }
diff --git a/src/background/reducers/index.js b/src/background/reducers/index.js
index 5729f0a..78f855c 100644
--- a/src/background/reducers/index.js
+++ b/src/background/reducers/index.js
@@ -10,9 +10,8 @@ const defaultState = {
 };
 
 export default function reducer(state = defaultState, action = {}) {
-  return Object.assign({}, state, {
+  return { ...state,
     setting: settingReducer(state.setting, action),
     find: findReducer(state.find, action),
-    tab: tabReducer(state.tab, action),
-  });
+    tab: tabReducer(state.tab, action), };
 }
diff --git a/src/background/reducers/setting.js b/src/background/reducers/setting.js
index 045a654..8dbc1b4 100644
--- a/src/background/reducers/setting.js
+++ b/src/background/reducers/setting.js
@@ -12,10 +12,8 @@ export default function reducer(state = defaultState, action = {}) {
     };
   case actions.SETTING_SET_PROPERTY:
     return {
-      value: Object.assign({}, state.value, {
-        properties: Object.assign({}, state.value.properties,
-          { [action.name]: action.value })
-      })
+      value: { ...state.value,
+        properties: { ...state.value.properties, [action.name]: action.value }}
     };
   default:
     return state;
diff --git a/src/console/reducers/index.js b/src/console/reducers/index.js
index 2aec55c..71b0776 100644
--- a/src/console/reducers/index.js
+++ b/src/console/reducers/index.js
@@ -51,68 +51,61 @@ const nextConsoleText = (completions, group, item, defaults) => {
   return completions[group].items[item].content;
 };
 
+// eslint-disable-next-line max-lines-per-function
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.CONSOLE_HIDE:
-    return Object.assign({}, state, {
-      mode: '',
-    });
+    return { ...state,
+      mode: '', };
   case actions.CONSOLE_SHOW_COMMAND:
-    return Object.assign({}, state, {
+    return { ...state,
       mode: 'command',
       consoleText: action.text,
-      completions: []
-    });
+      completions: []};
   case actions.CONSOLE_SHOW_FIND:
-    return Object.assign({}, state, {
+    return { ...state,
       mode: 'find',
       consoleText: '',
-      completions: []
-    });
+      completions: []};
   case actions.CONSOLE_SHOW_ERROR:
-    return Object.assign({}, state, {
+    return { ...state,
       mode: 'error',
-      messageText: action.text,
-    });
+      messageText: action.text, };
   case actions.CONSOLE_SHOW_INFO:
-    return Object.assign({}, state, {
+    return { ...state,
       mode: 'info',
-      messageText: action.text,
-    });
+      messageText: action.text, };
   case actions.CONSOLE_HIDE_COMMAND:
-    return Object.assign({}, state, {
+    return {
+      ...state,
       mode: state.mode === 'command' || state.mode === 'find' ? '' : state.mode,
-    });
+    };
   case actions.CONSOLE_SET_CONSOLE_TEXT:
-    return Object.assign({}, state, {
-      consoleText: action.consoleText,
-    });
+    return { ...state,
+      consoleText: action.consoleText, };
   case actions.CONSOLE_SET_COMPLETIONS:
-    return Object.assign({}, state, {
+    return { ...state,
       completions: action.completions,
       completionSource: action.completionSource,
       groupSelection: -1,
-      itemSelection: -1,
-    });
+      itemSelection: -1, };
   case actions.CONSOLE_COMPLETION_NEXT: {
     let next = nextSelection(state);
-    return Object.assign({}, state, {
+    return { ...state,
       groupSelection: next[0],
       itemSelection: next[1],
       consoleText: nextConsoleText(
         state.completions, next[0], next[1],
-        state.completionSource),
-    });
+        state.completionSource), };
   }
   case actions.CONSOLE_COMPLETION_PREV: {
     let next = prevSelection(state);
-    return Object.assign({}, state, {
+    return { ...state,
       groupSelection: next[0],
       itemSelection: next[1],
       consoleText: nextConsoleText(
         state.completions, next[0], next[1],
-        state.completionSource),
-    });
+        state.completionSource), };
   }
   default:
     return state;
diff --git a/src/content/actions/operation.js b/src/content/actions/operation.js
index 9171766..40ac52d 100644
--- a/src/content/actions/operation.js
+++ b/src/content/actions/operation.js
@@ -8,7 +8,7 @@ import * as consoleFrames from 'content/console-frames';
 import * as addonActions from './addon';
 import * as properties from 'shared/settings/properties';
 
-// eslint-disable-next-line complexity
+// eslint-disable-next-line complexity, max-lines-per-function
 const exec = (operation, repeat, settings) => {
   let smoothscroll = settings.properties.smoothscroll ||
     properties.defaults.smoothscroll;
diff --git a/src/content/actions/setting.js b/src/content/actions/setting.js
index 4c1e385..e34b6e0 100644
--- a/src/content/actions/setting.js
+++ b/src/content/actions/setting.js
@@ -10,7 +10,7 @@ const reservedKeymaps = {
 const set = (value) => {
   let entries = [];
   if (value.keymaps) {
-    let keymaps = Object.assign({}, value.keymaps, reservedKeymaps);
+    let keymaps = { ...value.keymaps, ...reservedKeymaps };
     entries = Object.entries(keymaps).map((entry) => {
       return [
         keyUtils.fromMapKeys(entry[0]),
@@ -21,9 +21,8 @@ const set = (value) => {
 
   return {
     type: actions.SETTING_SET,
-    value: Object.assign({}, value, {
-      keymaps: entries,
-    })
+    value: { ...value,
+      keymaps: entries, }
   };
 };
 
diff --git a/src/content/reducers/addon.js b/src/content/reducers/addon.js
index 8cc5ef1..b881ca0 100644
--- a/src/content/reducers/addon.js
+++ b/src/content/reducers/addon.js
@@ -7,17 +7,14 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.ADDON_ENABLE:
-    return Object.assign({}, state, {
-      enabled: true,
-    });
+    return { ...state,
+      enabled: true, };
   case actions.ADDON_DISABLE:
-    return Object.assign({}, state, {
-      enabled: false,
-    });
+    return { ...state,
+      enabled: false, };
   case actions.ADDON_TOGGLE_ENABLED:
-    return Object.assign({}, state, {
-      enabled: !state.enabled,
-    });
+    return { ...state,
+      enabled: !state.enabled, };
   default:
     return state;
   }
diff --git a/src/content/reducers/find.js b/src/content/reducers/find.js
index 8d63ee5..4560e2c 100644
--- a/src/content/reducers/find.js
+++ b/src/content/reducers/find.js
@@ -8,10 +8,9 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.FIND_SET_KEYWORD:
-    return Object.assign({}, state, {
+    return { ...state,
       keyword: action.keyword,
-      found: action.found,
-    });
+      found: action.found, };
   default:
     return state;
   }
diff --git a/src/content/reducers/follow-controller.js b/src/content/reducers/follow-controller.js
index 78fd848..5869c47 100644
--- a/src/content/reducers/follow-controller.js
+++ b/src/content/reducers/follow-controller.js
@@ -10,24 +10,20 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.FOLLOW_CONTROLLER_ENABLE:
-    return Object.assign({}, state, {
+    return { ...state,
       enabled: true,
       newTab: action.newTab,
       background: action.background,
-      keys: '',
-    });
+      keys: '', };
   case actions.FOLLOW_CONTROLLER_DISABLE:
-    return Object.assign({}, state, {
-      enabled: false,
-    });
+    return { ...state,
+      enabled: false, };
   case actions.FOLLOW_CONTROLLER_KEY_PRESS:
-    return Object.assign({}, state, {
-      keys: state.keys + action.key,
-    });
+    return { ...state,
+      keys: state.keys + action.key, };
   case actions.FOLLOW_CONTROLLER_BACKSPACE:
-    return Object.assign({}, state, {
-      keys: state.keys.slice(0, -1),
-    });
+    return { ...state,
+      keys: state.keys.slice(0, -1), };
   default:
     return state;
   }
diff --git a/src/content/reducers/index.js b/src/content/reducers/index.js
index 2487d85..c3a474e 100644
--- a/src/content/reducers/index.js
+++ b/src/content/reducers/index.js
@@ -14,11 +14,12 @@ const defaultState = {
 };
 
 export default function reducer(state = defaultState, action = {}) {
-  return Object.assign({}, state, {
+  return {
+    ...state,
     addon: addonReducer(state.addon, action),
     find: findReducer(state.find, action),
     setting: settingReducer(state.setting, action),
     input: inputReducer(state.input, action),
     followController: followControllerReducer(state.followController, action),
-  });
+  };
 }
diff --git a/src/content/reducers/input.js b/src/content/reducers/input.js
index 134aa95..23e7dd2 100644
--- a/src/content/reducers/input.js
+++ b/src/content/reducers/input.js
@@ -7,13 +7,11 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.INPUT_KEY_PRESS:
-    return Object.assign({}, state, {
-      keys: state.keys.concat([action.key]),
-    });
+    return { ...state,
+      keys: state.keys.concat([action.key]), };
   case actions.INPUT_CLEAR_KEYS:
-    return Object.assign({}, state, {
-      keys: [],
-    });
+    return { ...state,
+      keys: [], };
   default:
     return state;
   }
diff --git a/src/content/reducers/setting.js b/src/content/reducers/setting.js
index a23027f..a49db6d 100644
--- a/src/content/reducers/setting.js
+++ b/src/content/reducers/setting.js
@@ -8,7 +8,7 @@ const defaultState = {
 export default function reducer(state = defaultState, action = {}) {
   switch (action.type) {
   case actions.SETTING_SET:
-    return Object.assign({}, action.value);
+    return { ...action.value };
   default:
     return state;
   }
diff --git a/src/settings/components/form/keymaps-form.jsx b/src/settings/components/form/keymaps-form.jsx
index f0f69cf..dcf65d9 100644
--- a/src/settings/components/form/keymaps-form.jsx
+++ b/src/settings/components/form/keymaps-form.jsx
@@ -100,7 +100,7 @@ class KeymapsForm extends Component {
       return;
     }
 
-    let next = Object.assign({}, this.props.value);
+    let next = { ...this.props.value };
     next[e.target.name] = e.target.value;
 
     this.props.onChange(next);
diff --git a/src/settings/components/form/properties-form.jsx b/src/settings/components/form/properties-form.jsx
index 55c8512..ceb79d7 100644
--- a/src/settings/components/form/properties-form.jsx
+++ b/src/settings/components/form/properties-form.jsx
@@ -44,7 +44,7 @@ class PropertiesForm extends Component {
     }
 
     let name = e.target.name;
-    let next = Object.assign({}, this.props.value);
+    let next = { ...this.props.value };
     if (e.target.type.toLowerCase() === 'checkbox') {
       next[name] = e.target.checked;
     } else if (e.target.type.toLowerCase() === 'number') {
diff --git a/src/settings/components/form/search-form.jsx b/src/settings/components/form/search-form.jsx
index e85761f..2d5f01b 100644
--- a/src/settings/components/form/search-form.jsx
+++ b/src/settings/components/form/search-form.jsx
@@ -53,10 +53,10 @@ class SearchForm extends Component {
     let value = this.props.value;
     let name = e.target.name;
     let index = e.target.getAttribute('data-index');
-    let next = Object.assign({}, {
+    let next = {
       default: value.default,
       engines: value.engines ? value.engines.slice() : [],
-    });
+    };
 
     if (name === 'name') {
       next.engines[index][0] = e.target.value;
diff --git a/src/settings/components/index.jsx b/src/settings/components/index.jsx
index e13bfa1..c479986 100644
--- a/src/settings/components/index.jsx
+++ b/src/settings/components/index.jsx
@@ -134,7 +134,7 @@ class SettingsComponent extends Component {
   }
 
   validateValue(e) {
-    let next = Object.assign({}, this.state);
+    let next = { ...this.state };
 
     next.errors.json = '';
     try {
@@ -146,18 +146,16 @@ class SettingsComponent extends Component {
   }
 
   bindForm(name, value) {
-    let next = Object.assign({}, this.state, {
-      settings: Object.assign({}, this.state.settings, {
-        form: Object.assign({}, this.state.settings.form)
-      })
-    });
+    let next = { ...this.state,
+      settings: { ...this.state.settings,
+        form: { ...this.state.settings.form }}};
     next.settings.form[name] = value;
     this.setState(next);
     this.context.store.dispatch(settingActions.save(next.settings));
   }
 
   bindValue(e) {
-    let next = Object.assign({}, this.state);
+    let next = { ...this.state };
     let error = false;
 
     next.errors.json = '';
@@ -190,7 +188,7 @@ class SettingsComponent extends Component {
 
     let form = settingsValues.formFromJson(
       this.state.settings.json, KeymapsForm.AllowdOps);
-    let next = Object.assign({}, this.state);
+    let next = { ...this.state };
     next.settings.form = form;
     next.settings.source = 'form';
     next.errors.json = '';
@@ -201,7 +199,7 @@ class SettingsComponent extends Component {
 
   migrateToJson() {
     let json = settingsValues.jsonFromForm(this.state.settings.form);
-    let next = Object.assign({}, this.state);
+    let next = { ...this.state };
     next.settings.json = json;
     next.settings.source = 'json';
     next.errors.json = '';
diff --git a/src/shared/settings/storage.js b/src/shared/settings/storage.js
index 87843ed..5dce3b0 100644
--- a/src/shared/settings/storage.js
+++ b/src/shared/settings/storage.js
@@ -6,7 +6,7 @@ const loadRaw = async() => {
   if (!settings) {
     return DefaultSettings;
   }
-  return Object.assign({}, DefaultSettings, settings);
+  return { ...DefaultSettings, ...settings };
 };
 
 const loadValue = async() => {
@@ -20,9 +20,7 @@ const loadValue = async() => {
   if (!value.properties) {
     value.properties = {};
   }
-  return Object.assign({},
-    settingsValues.valueFromJson(DefaultSettings.json),
-    value);
+  return { ...settingsValues.valueFromJson(DefaultSettings.json), ...value };
 };
 
 const save = (settings) => {
diff --git a/src/shared/settings/values.js b/src/shared/settings/values.js
index bd03be2..9828af6 100644
--- a/src/shared/settings/values.js
+++ b/src/shared/settings/values.js
@@ -6,12 +6,12 @@ const operationFromFormName = (name) => {
   if (argStr) {
     args = JSON.parse(argStr);
   }
-  return Object.assign({ type }, args);
+  return { type, ...args };
 };
 
 const operationToFormName = (op) => {
   let type = op.type;
-  let args = Object.assign({}, op);
+  let args = { ...op };
   delete args.type;
 
   if (Object.keys(args).length === 0) {
@@ -83,7 +83,7 @@ const formFromValue = (value, allowedOps) => {
     }
   }
 
-  let formProperties = Object.assign({}, properties.defaults, value.properties);
+  let formProperties = { ...properties.defaults, ...value.properties };
 
   return {
     keymaps,
diff --git a/webpack.config.js b/webpack.config.js
index 6c855e5..90fd526 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -24,7 +24,7 @@ config = {
         exclude: /node_modules/,
         loader: 'babel-loader',
         query: {
-          presets: ['preact']
+          presets: ['preact', 'stage-2']
         }
       },
       {