add flow types

Author: dashed

.flowconfig

@@ -0,0 +1,11 @@
+[ignore]
+
+[include]
+
+[libs]
+
+[lints]
+
+[options]
+
+[strict]

index.js

@@ -1,3 +1,5 @@
+//
+
 module.exports = function shallowEqual(objA, objB, compare, compareContext) {
   var ret = compare ? compare.call(compareContext, objA, objB) : void 0;
 

index.js.flow

@@ -0,0 +1,8 @@
+// @flow
+
+declare module.exports: <T, U>(
+  objA?: ?T,
+  objB?: ?U,
+  compare?: ?(objValue: any, otherValue: any, key?: string) => boolean | void,
+  compareContext?: ?any
+) => boolean;

index.original.js

@@ -0,0 +1,51 @@
+// @flow
+
+module.exports = function shallowEqual<T, U>(
+  objA?: ?T,
+  objB?: ?U,
+  compare?: ?(objValue: any, otherValue: any, key?: string) => boolean | void,
+  compareContext?: ?any
+): boolean {
+  var ret = compare ? compare.call(compareContext, objA, objB) : void 0;
+
+  if (ret !== void 0) {
+    return !!ret;
+  }
+
+  if (objA === objB) {
+    return true;
+  }
+
+  if (typeof objA !== "object" || !objA || typeof objB !== "object" || !objB) {
+    return false;
+  }
+
+  var keysA = Object.keys(objA);
+  var keysB = Object.keys(objB);
+
+  if (keysA.length !== keysB.length) {
+    return false;
+  }
+
+  var bHasOwnProperty = Object.prototype.hasOwnProperty.bind(objB);
+
+  // Test for A's keys different from B.
+  for (var idx = 0; idx < keysA.length; idx++) {
+    var key = keysA[idx];
+
+    if (!bHasOwnProperty(key)) {
+      return false;
+    }
+
+    var valueA = objA[key];
+    var valueB = objB[key];
+
+    ret = compare ? compare.call(compareContext, valueA, valueB, key) : void 0;
+
+    if (ret === false || (ret === void 0 && valueA !== valueB)) {
+      return false;
+    }
+  }
+
+  return true;
+};

package.json

@@ -6,13 +6,18 @@
   "scripts": {
     "lint": "eslint index.js test",
     "test": "mocha --require babel-register",
-    "prepublish": "npm run lint && npm run test",
+    "build:strip-flow":
+      "flow-remove-types --pretty index.original.js > index.js",
+    "build:gen-flow": "flow gen-flow-files index.original.js > index.js.flow",
+    "build": "npm run build:strip-flow && npm run build:gen-flow",
+    "prepublish":
+      "npm run build && npm run pretty && npm run lint && npm run test",
     "travis": "npm run lint && npm run test",
-    "pretty": "prettier --write --tab-width 2 'test/**/*.js' '*.js'",
+    "pretty": "prettier --write --tab-width 2 'test/**/*.js' '*.{js,js.flow}'",
     "precommit": "lint-staged"
   },
   "lint-staged": {
-    "*.{js,json,css}": ["prettier --write", "git add"]
+    "*.{js,json,css,js.flow}": ["prettier --write", "git add"]
   },
   "author": {
     "name": "Alberto Leal",
@@ -21,7 +26,7 @@
   },
   "repository": "dashed/shallowequal",
   "license": "MIT",
-  "files": ["index.js"],
+  "files": ["index.js", "index.js.flow", "index.original.js"],
   "keywords": [
     "shallowequal",
     "shallow",
@@ -45,6 +50,8 @@
     "babel-register": "^6.24.1",
     "chai": "^4.0.0",
     "eslint": "^4.7.1",
+    "flow-bin": "^0.72.0",
+    "flow-remove-types": "^1.2.3",
     "husky": "^0.14.3",
     "lint-staged": "^6.0.0",
     "mocha": "^5.0.0",

yarn.lock

@@ -632,7 +632,7 @@ babylon@7.0.0-beta.44:
   version "7.0.0-beta.44"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-7.0.0-beta.44.tgz#89159e15e6e30c5096e22d738d8c0af8a0e8ca1d"
 
-babylon@^6.18.0:
+babylon@^6.15.0, babylon@^6.18.0:
   version "6.18.0"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-6.18.0.tgz#af2f3b88fa6f5c1e4c634d1a0f8eac4f55b395e3"
 
@@ -1046,6 +1046,17 @@ flat-cache@^1.2.1:
     graceful-fs "^4.1.2"
     write "^0.2.1"
 
+flow-bin@^0.72.0:
+  version "0.72.0"
+  resolved "https://registry.yarnpkg.com/flow-bin/-/flow-bin-0.72.0.tgz#12051180fb2db7ccb728fefe67c77e955e92a44d"
+
+flow-remove-types@^1.2.3:
+  version "1.2.3"
+  resolved "https://registry.yarnpkg.com/flow-remove-types/-/flow-remove-types-1.2.3.tgz#6131aefc7da43364bb8b479758c9dec7735d1a18"
+  dependencies:
+    babylon "^6.15.0"
+    vlq "^0.2.1"
+
 fs.realpath@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/fs.realpath/-/fs.realpath-1.0.0.tgz#1504ad2523158caa40db4a2787cb01411994ea4f"
@@ -1976,6 +1987,10 @@ util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
 
+vlq@^0.2.1:
+  version "0.2.3"
+  resolved "https://registry.yarnpkg.com/vlq/-/vlq-0.2.3.tgz#8f3e4328cf63b1540c0d67e1b2778386f8975b26"
+
 which@^1.2.10, which@^1.2.9:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/which/-/which-1.3.0.tgz#ff04bdfc010ee547d780bec38e1ac1c2777d253a"