Do not enable subdomain matching by default

Updated tests for new subdomain matching
Added a test to validate matching behavior

tests/test_basic.py

@@ -1429,10 +1429,12 @@ def test_request_locals():
     assert not flask.g
 
 
-def test_test_app_proper_environ(app, client):
+def test_test_app_proper_environ():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config.update(
         SERVER_NAME='localhost.localdomain:5000'
     )
+    client = app.test_client()
 
     @app.route('/')
     def index():
@@ -1783,8 +1785,10 @@ def test_g_iteration_protocol(app_ctx):
     assert sorted(flask.g) == ['bar', 'foo']
 
 
-def test_subdomain_basic_support(app, client):
+def test_subdomain_basic_support():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'localhost.localdomain'
+    client = app.test_client()
 
     @app.route('/')
     def normal_index():
@@ -1801,7 +1805,9 @@ def test_subdomain_basic_support(app, client):
     assert rv.data == b'test index'
 
 
-def test_subdomain_matching(app, client):
+def test_subdomain_matching():
+    app = flask.Flask(__name__, subdomain_matching=True)
+    client = app.test_client()
     app.config['SERVER_NAME'] = 'localhost.localdomain'
 
     @app.route('/', subdomain='<user>')
@@ -1812,8 +1818,10 @@ def test_subdomain_matching(app, client):
     assert rv.data == b'index for mitsuhiko'
 
 
-def test_subdomain_matching_with_ports(app, client):
+def test_subdomain_matching_with_ports():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'localhost.localdomain:3000'
+    client = app.test_client()
 
     @app.route('/', subdomain='<user>')
     def index(user):
@@ -1823,6 +1831,23 @@ def test_subdomain_matching_with_ports(app, client):
     assert rv.data == b'index for mitsuhiko'
 
 
+def test_subdomain_matching_behavior():
+    for matching in False, True:
+        app = flask.Flask(__name__, subdomain_matching=matching)
+        app.config['SERVER_NAME'] = 'localhost.localdomain:3000'
+        client = app.test_client()
+
+        @app.route('/')
+        def index():
+            return 'matched without subdomain'
+
+        rv = client.get('/', 'http://127.0.0.1:3000/')
+        if matching:
+            assert rv.status_code == 404
+        else:
+            assert rv.data == b'matched without subdomain'
+
+
 def test_multi_route_rules(app, client):
     @app.route('/')
     @app.route('/<test>/')