Remove the Underscore.js dependency.

CHANGELOG.md

@@ -1,3 +1,6 @@
+## Unreleased
+- Removes the [Underscore.js](https://underscorejs.org) dependency in favor of just inlining two rewritten helper functions.
+
 ## 1.7.2 (May 1, 2021)
 - Increases the upper-bound on [Underscore.js](https://underscorejs.org) dependency to v1.13 (inclusive).  
   Thanks, [Martin Caruso](https://github.com/mcaruso85), for the heads-up.

index.js

@@ -1,4 +1,3 @@
-var _ = require("underscore")
 var Net = require("net")
 var Tls = require("tls")
 var Http = require("http")
@@ -66,7 +65,7 @@ Mitm.prototype.enable = function() {
   // ClientRequest.prototype.onSocket is called synchronously from
   // ClientRequest's constructor and is a convenient place to hook into new
   // ClientRequests.
-  this.stubs.stub(ClientRequest.prototype, "onSocket", _.compose(
+  this.stubs.stub(ClientRequest.prototype, "onSocket", compose(
     ClientRequest.prototype.onSocket,
     this.request.bind(this)
   ))
@@ -84,7 +83,7 @@ Mitm.prototype.connect = function connect(orig, Socket, opts, done) {
   // Don't set client.connecting to false because there's nothing setting it
   // back to false later. Originally that was done in Socket.prototype.connect
   // and its afterConnect handler, but we're not calling that.
-  var client = new Socket(_.defaults({
+  var client = new Socket(defaults({
     handle: sockets[0],
 
     // Node v10 expects readable and writable to be set at Socket creation time.
@@ -153,11 +152,30 @@ Mitm.prototype.request = function request(socket) {
   var self = this
   if (NODE_0_10) {
     self = Object.create(this)
-    self.emit = _.compose(process.nextTick, Function.bind.bind(this.emit, this))
+    self.emit = compose(process.nextTick, Function.bind.bind(this.emit, this))
   }
 
   createRequestAndResponse.call(self, socket.serverSocket)
   return socket
 }
 
+function compose() {
+  var fns = arguments
+
+  return function() {
+    var args = arguments
+    for (var i = fns.length - 1; i >= 0; --i) args = [fns[i].apply(this, args)]
+    return args[0]
+  }
+}
+
+function defaults(target) {
+  if (target != null) for (var i = 1; i < arguments.length; ++i) {
+    var source = arguments[i]
+    for (var key in source) if (!(key in target)) target[key] = source[key]
+  }
+
+  return target
+}
+
 function addCrossReferences(req, res) { req.res = res; res.req = req }

package.json

@@ -33,14 +33,14 @@
 	"scripts": {"test": "make test"},
 
 	"dependencies": {
-		"underscore": ">= 1.1.6 < 1.14",
 		"semver": ">= 5 < 6"
 	},
 
 	"devDependencies": {
 		"mocha": ">= 1.12.0 < 3",
 		"must": ">= 0.13 < 0.14",
-		"sinon": ">= 1.9 < 2"
+		"sinon": ">= 1.9 < 2",
+		"underscore": ">= 1.1.6 < 1.14"
 	},
 
 	"engines": {"node": ">= 0.10.24"}