Use mocks

Behavior for REPL tests has been inconsistent across the board.
For example, see

https://ci.appveyor.com/project/kgryte/stdlib/build/2659/job/bi7n1aynmty3yhvr

In short, `close` events would often not fire and the process would
die, causing downstream events, such as subsequent tests would
never run. The main aim of the REPL tests is to ensure that a REPL
starts, with an eye toward ensuring that all dependencies are
capable of being loaded into the REPL (i.e., no broken requires).
Using mocks still satisfies these concerns, as the REPL context is
still populated on the mock REPL dependency.

Author: kgryte

lib/node_modules/@stdlib/repl/test/test.js

@@ -3,6 +3,7 @@
 // MODULES //
 
 var tape = require( 'tape' );
+var proxyquire = require( 'proxyquire' );
 var noop = require( '@stdlib/utils/noop' );
 var repl = require( './../lib' );
 
@@ -100,45 +101,63 @@ tape( 'the function throws an error if provided a callback argument which is not
 });
 
 tape( 'the function starts a REPL environment', function test( t ) {
+	var repl;
+	var mock;
+
+	mock = {
+		'start': start
+	};
+
+	repl = proxyquire( './../lib/repl.js', {
+		'repl': mock
+	});
+
 	repl( onStart );
 
+	function start() {
+		return {
+			'context': {}
+		};
+	}
+
 	function onStart( error, server ) {
 		if ( error ) {
 			t.ok( false, error.message );
-			return t.end();
+		} else {
+			t.ok( true, 'starts a REPL' );
+			t.ok( server, 'returns a REPL server' );
 		}
-		t.ok( true, 'starts a REPL' );
-		server.rli.on( 'close', onClose );
-		server.rli.write( '.exit\n' );
-	}
-
-	function onClose() {
-		setTimeout( onEnd, 1000 );
-	}
-
-	function onEnd() {
 		t.end();
 	}
 });
 
 tape( 'the function starts a REPL environment (options)', function test( t ) {
+	var repl;
+	var mock;
+
+	mock = {
+		'start': start
+	};
+
+	repl = proxyquire( './../lib/repl.js', {
+		'repl': mock
+	});
+
 	repl( {}, onStart );
 
+	function start() {
+		return {
+			'context': {}
+		};
+	}
+
 	function onStart( error, server ) {
 		if ( error ) {
 			t.ok( false, error.message );
-			return t.end();
+		} else {
+			t.ok( true, 'starts a REPL' );
+			t.ok( server, 'returns a REPL server' );
 		}
-		t.ok( true, 'starts a REPL' );
-		server.rli.on( 'close', onClose );
-		server.rli.write( '.exit\n' );
-	}
-
-	function onClose() {
-		setTimeout( onEnd, 1000 );
-	}
-
-	function onEnd() {
 		t.end();
 	}
 });