Update packages.

package-lock.json

@@ -5672,6 +5672,12 @@
         "mem": "^1.1.0"
       }
     },
+    "os-shim": {
+      "version": "0.1.3",
+      "resolved": "https://registry.npmjs.org/os-shim/-/os-shim-0.1.3.tgz",
+      "integrity": "sha1-a2LDeRz3kJ6jXtRuF2WLtBfLORc=",
+      "dev": true
+    },
     "os-tmpdir": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/os-tmpdir/-/os-tmpdir-1.0.2.tgz",
@@ -5848,6 +5854,28 @@
       "integrity": "sha1-AerA/jta9xoqbAL+q7jB/vfgDqs=",
       "dev": true
     },
+    "pre-commit": {
+      "version": "1.2.2",
+      "resolved": "https://registry.npmjs.org/pre-commit/-/pre-commit-1.2.2.tgz",
+      "integrity": "sha1-287g7p3nI15X95xW186UZBpp7sY=",
+      "dev": true,
+      "requires": {
+        "cross-spawn": "^5.0.1",
+        "spawn-sync": "^1.0.15",
+        "which": "1.2.x"
+      },
+      "dependencies": {
+        "which": {
+          "version": "1.2.14",
+          "resolved": "https://registry.npmjs.org/which/-/which-1.2.14.tgz",
+          "integrity": "sha1-mofEN48D6CfOyvGs31bHNsAcFOU=",
+          "dev": true,
+          "requires": {
+            "isexe": "^2.0.0"
+          }
+        }
+      }
+    },
     "prelude-ls": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.1.2.tgz",
@@ -6905,6 +6933,16 @@
       "integrity": "sha1-PpNdfd1zYxuXZZlW1VEo6HtQhKM=",
       "dev": true
     },
+    "spawn-sync": {
+      "version": "1.0.15",
+      "resolved": "https://registry.npmjs.org/spawn-sync/-/spawn-sync-1.0.15.tgz",
+      "integrity": "sha1-sAeZVX63+wyDdsKdROih6mfldHY=",
+      "dev": true,
+      "requires": {
+        "concat-stream": "^1.4.7",
+        "os-shim": "^0.1.2"
+      }
+    },
     "spdx-correct": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/spdx-correct/-/spdx-correct-3.0.0.tgz",

package.json

@@ -9,6 +9,10 @@
     "ci": "npm run lint && npm run test -- --coverage",
     "codecov": "codecov"
   },
+  "pre-commit": [
+    "lint",
+    "test"
+  ],
   "repository": {
     "type": "git",
     "url": "git+https://github.com/trekhleb/javascript-algorithms.git"
@@ -39,7 +43,8 @@
     "eslint-plugin-jest": "^21.15.1",
     "eslint-plugin-jsx-a11y": "^6.0.3",
     "eslint-plugin-react": "^7.7.0",
-    "jest": "^22.4.3"
+    "jest": "^22.4.3",
+    "pre-commit": "^1.2.2"
   },
   "dependencies": {}
 }