diff --git a/CHANGES.rst b/CHANGES.rst
index 0942aea6..a383f3f4 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -30,7 +30,7 @@ Unreleased
 Version 1.0.3
 -------------
 
-Unreleased
+Released 2019-05-17
 
 -   :func:`send_file` encodes filenames as ASCII instead of Latin-1
     (ISO-8859-1). This fixes compatibility with Gunicorn, which is
@@ -46,10 +46,13 @@ Unreleased
     handle ``RoutingException``, which is used internally during
     routing. This fixes the unexpected behavior that had been introduced
     in 1.0. (`#2986`_)
+-   Passing the ``json`` argument to ``app.test_client`` does not
+    push/pop an extra app context. (`#2900`_)
 
 .. _#2766: https://github.com/pallets/flask/issues/2766
 .. _#2765: https://github.com/pallets/flask/pull/2765
 .. _#2825: https://github.com/pallets/flask/pull/2825
+.. _#2900: https://github.com/pallets/flask/issues/2900
 .. _#2933: https://github.com/pallets/flask/issues/2933
 .. _#2986: https://github.com/pallets/flask/pull/2986
 
@@ -57,7 +60,7 @@ Unreleased
 Version 1.0.2
 -------------
 
-Released on May 2nd 2018
+Released 2018-05-02
 
 -   Fix more backwards compatibility issues with merging slashes between
     a blueprint prefix and route. (`#2748`_)
@@ -71,7 +74,7 @@ Released on May 2nd 2018
 Version 1.0.1
 -------------
 
-Released on April 29th 2018
+Released 2018-04-29
 
 -   Fix registering partials (with no ``__name__``) as view functions.
     (`#2730`_)
@@ -97,7 +100,7 @@ Released on April 29th 2018
 Version 1.0
 -----------
 
-Released on April 26th 2018
+Released 2018-04-26
 
 -   **Python 2.6 and 3.3 are no longer supported.** (`pallets/meta#24`_)
 -   Bump minimum dependency versions to the latest stable versions:
diff --git a/docs/testing.rst b/docs/testing.rst
index a18aca6c..ed9f0b03 100644
--- a/docs/testing.rst
+++ b/docs/testing.rst
@@ -357,14 +357,15 @@ This however does not make it possible to also modify the session or to
 access the session before a request was fired.  Starting with Flask 0.8 we
 provide a so called “session transaction” which simulates the appropriate
 calls to open a session in the context of the test client and to modify
-it.  At the end of the transaction the session is stored.  This works
-independently of the session backend used::
+it. At the end of the transaction the session is stored and ready to be
+used by the test client. This works independently of the session backend used::
 
     with app.test_client() as c:
         with c.session_transaction() as sess:
             sess['a_key'] = 'a value'
 
-        # once this is reached the session was stored
+        # once this is reached the session was stored and ready to be used by the client
+        c.get(...)
 
 Note that in this case you have to use the ``sess`` object instead of the
 :data:`flask.session` proxy.  The object however itself will provide the
diff --git a/flask/blueprints.py b/flask/blueprints.py
index 42702d6d..dc193a8d 100644
--- a/flask/blueprints.py
+++ b/flask/blueprints.py
@@ -10,7 +10,6 @@
     :license: BSD, see LICENSE for more details.
 """
 from functools import update_wrapper
-from werkzeug.urls import url_join
 
 from .helpers import _PackageBoundObject, _endpoint_from_view_func
 
diff --git a/flask/cli.py b/flask/cli.py
index 6bb01a1f..d96f16f6 100644
--- a/flask/cli.py
+++ b/flask/cli.py
@@ -650,11 +650,9 @@ def show_server_banner(env, debug, app_import_path, eager_loading):
 
     if env == "production":
         click.secho(
-            "   WARNING: Do not use the development server in a production"
-            " environment.",
-            fg="red",
-        )
-        click.secho("   Use a production WSGI server instead.", dim=True)
+            '   WARNING: This is a development server. '
+            'Do not use it in a production deployment.', fg='red')
+        click.secho('   Use a production WSGI server instead.', dim=True)
 
     if debug is not None:
         click.echo(" * Debug mode: {0}".format("on" if debug else "off"))
diff --git a/flask/json/__init__.py b/flask/json/__init__.py
index 80019250..ac9847dd 100644
--- a/flask/json/__init__.py
+++ b/flask/json/__init__.py
@@ -97,31 +97,35 @@ class JSONDecoder(_json.JSONDecoder):
     """
 
 
-def _dump_arg_defaults(kwargs):
+def _dump_arg_defaults(kwargs, app=None):
     """Inject default arguments for dump functions."""
-    if current_app:
-        bp = current_app.blueprints.get(request.blueprint) if request else None
+    if app is None:
+        app = current_app
+
+    if app:
+        bp = app.blueprints.get(request.blueprint) if request else None
         kwargs.setdefault(
-            "cls",
-            bp.json_encoder if bp and bp.json_encoder else current_app.json_encoder,
+            "cls", bp.json_encoder if bp and bp.json_encoder else app.json_encoder
         )
 
-        if not current_app.config["JSON_AS_ASCII"]:
+        if not app.config["JSON_AS_ASCII"]:
             kwargs.setdefault("ensure_ascii", False)
 
-        kwargs.setdefault("sort_keys", current_app.config["JSON_SORT_KEYS"])
+        kwargs.setdefault("sort_keys", app.config["JSON_SORT_KEYS"])
     else:
         kwargs.setdefault("sort_keys", True)
         kwargs.setdefault("cls", JSONEncoder)
 
 
-def _load_arg_defaults(kwargs):
+def _load_arg_defaults(kwargs, app=None):
     """Inject default arguments for load functions."""
-    if current_app:
-        bp = current_app.blueprints.get(request.blueprint) if request else None
+    if app is None:
+        app = current_app
+
+    if app:
+        bp = app.blueprints.get(request.blueprint) if request else None
         kwargs.setdefault(
-            "cls",
-            bp.json_decoder if bp and bp.json_decoder else current_app.json_decoder,
+            "cls", bp.json_decoder if bp and bp.json_decoder else app.json_decoder
         )
     else:
         kwargs.setdefault("cls", JSONDecoder)
@@ -170,17 +174,28 @@ def detect_encoding(data):
     return "utf-8"
 
 
-def dumps(obj, **kwargs):
-    """Serialize ``obj`` to a JSON formatted ``str`` by using the application's
-    configured encoder (:attr:`~flask.Flask.json_encoder`) if there is an
-    application on the stack.
+def dumps(obj, app=None, **kwargs):
+    """Serialize ``obj`` to a JSON-formatted string. If there is an
+    app context pushed, use the current app's configured encoder
+    (:attr:`~flask.Flask.json_encoder`), or fall back to the default
+    :class:`JSONEncoder`.
 
-    This function can return ``unicode`` strings or ascii-only bytestrings by
-    default which coerce into unicode strings automatically.  That behavior by
-    default is controlled by the ``JSON_AS_ASCII`` configuration variable
-    and can be overridden by the simplejson ``ensure_ascii`` parameter.
+    Takes the same arguments as the built-in :func:`json.dumps`, and
+    does some extra configuration based on the application. If the
+    simplejson package is installed, it is preferred.
+
+    :param obj: Object to serialize to JSON.
+    :param app: App instance to use to configure the JSON encoder.
+        Uses ``current_app`` if not given, and falls back to the default
+        encoder when not in an app context.
+    :param kwargs: Extra arguments passed to :func:`json.dumps`.
+
+    .. versionchanged:: 1.0.3
+
+        ``app`` can be passed directly, rather than requiring an app
+        context for configuration.
     """
-    _dump_arg_defaults(kwargs)
+    _dump_arg_defaults(kwargs, app=app)
     encoding = kwargs.pop("encoding", None)
     rv = _json.dumps(obj, **kwargs)
     if encoding is not None and isinstance(rv, text_type):
@@ -188,21 +203,37 @@ def dumps(obj, **kwargs):
     return rv
 
 
-def dump(obj, fp, **kwargs):
+def dump(obj, fp, app=None, **kwargs):
     """Like :func:`dumps` but writes into a file object."""
-    _dump_arg_defaults(kwargs)
+    _dump_arg_defaults(kwargs, app=app)
     encoding = kwargs.pop("encoding", None)
     if encoding is not None:
         fp = _wrap_writer_for_text(fp, encoding)
     _json.dump(obj, fp, **kwargs)
 
 
-def loads(s, **kwargs):
-    """Unserialize a JSON object from a string ``s`` by using the application's
-    configured decoder (:attr:`~flask.Flask.json_decoder`) if there is an
-    application on the stack.
+def loads(s, app=None, **kwargs):
+    """Deserialize an object from a JSON-formatted string ``s``. If
+    there is an app context pushed, use the current app's configured
+    decoder (:attr:`~flask.Flask.json_decoder`), or fall back to the
+    default :class:`JSONDecoder`.
+
+    Takes the same arguments as the built-in :func:`json.loads`, and
+    does some extra configuration based on the application. If the
+    simplejson package is installed, it is preferred.
+
+    :param s: JSON string to deserialize.
+    :param app: App instance to use to configure the JSON decoder.
+        Uses ``current_app`` if not given, and falls back to the default
+        encoder when not in an app context.
+    :param kwargs: Extra arguments passed to :func:`json.dumps`.
+
+    .. versionchanged:: 1.0.3
+
+        ``app`` can be passed directly, rather than requiring an app
+        context for configuration.
     """
-    _load_arg_defaults(kwargs)
+    _load_arg_defaults(kwargs, app=app)
     if isinstance(s, bytes):
         encoding = kwargs.pop("encoding", None)
         if encoding is None:
@@ -211,10 +242,9 @@ def loads(s, **kwargs):
     return _json.loads(s, **kwargs)
 
 
-def load(fp, **kwargs):
-    """Like :func:`loads` but reads from a file object.
-    """
-    _load_arg_defaults(kwargs)
+def load(fp, app=None, **kwargs):
+    """Like :func:`loads` but reads from a file object."""
+    _load_arg_defaults(kwargs, app=app)
     if not PY2:
         fp = _wrap_reader_for_text(fp, kwargs.pop("encoding", None) or "utf-8")
     return _json.load(fp, **kwargs)
diff --git a/flask/testing.py b/flask/testing.py
index 514a63b4..6c9de313 100644
--- a/flask/testing.py
+++ b/flask/testing.py
@@ -71,12 +71,10 @@ def make_test_environ_builder(
             sep = b"?" if isinstance(url.query, bytes) else "?"
             path += sep + url.query
 
+    # TODO use EnvironBuilder.json_dumps once we require Werkzeug 0.15
     if "json" in kwargs:
         assert "data" not in kwargs, "Client cannot provide both 'json' and 'data'."
-
-        # push a context so flask.json can use app's json attributes
-        with app.app_context():
-            kwargs["data"] = json_dumps(kwargs.pop("json"))
+        kwargs["data"] = json_dumps(kwargs.pop("json"), app=app)
 
         if "content_type" not in kwargs:
             kwargs["content_type"] = "application/json"
diff --git a/tests/test_testing.py b/tests/test_testing.py
index ad5ed0cb..a6b9d70e 100644
--- a/tests/test_testing.py
+++ b/tests/test_testing.py
@@ -14,11 +14,17 @@ import pytest
 import flask
 import werkzeug
 
+from flask import appcontext_popped
 from flask._compat import text_type
 from flask.cli import ScriptInfo
 from flask.json import jsonify
 from flask.testing import make_test_environ_builder, FlaskCliRunner
 
+try:
+    import blinker
+except ImportError:
+    blinker = None
+
 
 def test_environ_defaults_from_config(app, client):
     app.config["SERVER_NAME"] = "example.com:1234"
@@ -306,6 +312,27 @@ def test_json_request_and_response(app, client):
         assert rv.get_json() == json_data
 
 
+@pytest.mark.skipif(blinker is None, reason="blinker is not installed")
+def test_client_json_no_app_context(app, client):
+    @app.route("/hello", methods=["POST"])
+    def hello():
+        return "Hello, {}!".format(flask.request.json["name"])
+
+    class Namespace(object):
+        count = 0
+
+        def add(self, app):
+            self.count += 1
+
+    ns = Namespace()
+
+    with appcontext_popped.connected_to(ns.add, app):
+        rv = client.post("/hello", json={"name": "Flask"})
+
+    assert rv.get_data(as_text=True) == "Hello, Flask!"
+    assert ns.count == 1
+
+
 def test_subdomain():
     app = flask.Flask(__name__, subdomain_matching=True)
     app.config["SERVER_NAME"] = "example.com"