Add support for jsonschema 4.x

jsonschema 4.0 was released in September 2021. It's time to support it.
Only one issue to address in our tests, namely that when specifying the
'items' key for a property of type 'array', the value should be an
object, not an array of objects.

  Good:

    {
      "type": "object",
      "properties": {
        "fruits": {
          "type": "array",
          "items": { "type": "string" }
        }
      }
    }

  Bad:

    {
      "type": "object",
      "properties": {
        "fruits": {
          "type": "array",
          "items": [{ "type": "string" }]
        }
      }
    }

The docs say as much [1].

[1] https://json-schema.org/learn/miscellaneous-examples.html#arrays-of-things

Signed-off-by: Stephen Finucane <stephen@that.guru>
Closes: #64

4 files changed, 11 insertions, 11 deletions

diff --git a/poetry.lock b/poetry.lock
index 231094e..c1a92d4 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -72,7 +72,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
 name = "jsonschema"
-version = "3.2.0"
+version = "4.0.0"
 description = "An implementation of JSON Schema validation for Python"
 category = "main"
 optional = false
@@ -81,12 +81,11 @@ python-versions = "*"
 [package.dependencies]
 attrs = ">=17.4.0"
 importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
-pyrsistent = ">=0.14.0"
-six = ">=1.11.0"
+pyrsistent = ">=0.14.0,<0.17.0 || >0.17.0,<0.17.1 || >0.17.1,<0.17.2 || >0.17.2"
 
 [package.extras]
-format = ["idna", "jsonpointer (>1.13)", "rfc3987", "strict-rfc3339", "webcolors"]
-format_nongpl = ["idna", "jsonpointer (>1.13)", "webcolors", "rfc3986-validator (>0.1.0)", "rfc3339-validator"]
+format = ["fqdn", "idna", "isoduration", "jsonpointer (>1.13)", "rfc3339-validator", "rfc3987", "uri-template", "webcolors (>=1.11)"]
+format_nongpl = ["fqdn", "idna", "isoduration", "jsonpointer (>1.13)", "rfc3339-validator", "rfc3986-validator (>0.1.0)", "uri-template", "webcolors (>=1.11)"]
 
 [[package]]
 name = "more-itertools"
@@ -232,7 +231,7 @@ testing = ["pathlib2", "contextlib2", "unittest2"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.5"
-content-hash = "163b233661736ad8b168e8c19509e93349e9f16b1be1012712114f3e1f447296"
+content-hash = "21e79f003cee0c519454cf16aaefcbff49f8d8c68d29290c0a1f4cb59f1fa8a8"
 
 [metadata.files]
 atomicwrites = [
@@ -294,8 +293,8 @@ jsonpointer = [
     {file = "jsonpointer-2.0.tar.gz", hash = "sha256:c192ba86648e05fdae4f08a17ec25180a9aef5008d973407b581798a83975362"},
 ]
 jsonschema = [
-    {file = "jsonschema-3.2.0-py2.py3-none-any.whl", hash = "sha256:4e5b3cf8216f577bee9ce139cbe72eca3ea4f292ec60928ff24758ce626cd163"},
-    {file = "jsonschema-3.2.0.tar.gz", hash = "sha256:c8a85b28d377cc7737e46e2d9f2b4f44ee3c0e1deac6bf46ddefc7187d30797a"},
+    {file = "jsonschema-4.0.0-py3-none-any.whl", hash = "sha256:c773028c649441ab980015b5b622f4cd5134cf563daaf0235ca4b73cc3734f20"},
+    {file = "jsonschema-4.0.0.tar.gz", hash = "sha256:bc51325b929171791c42ebc1c70b9713eb134d3bb8ebd5474c8b659b15be6d86"},
 ]
 more-itertools = [
     {file = "more-itertools-8.0.2.tar.gz", hash = "sha256:b84b238cce0d9adad5ed87e745778d20a3f8487d0f0cb8b8a586816c7496458d"},
diff --git a/pyproject.toml b/pyproject.toml
index db3e6ec..1e7479b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,7 +29,7 @@ packages = [
 
 [tool.poetry.dependencies]
 python = "^3.5"
-jsonschema = "^3"
+jsonschema = "^4"
 jsonpatch = "^1"
 
 [tool.poetry.dev-dependencies]
diff --git a/tests/test_core.py b/tests/test_core.py
index bc36c92..390e61c 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -38,7 +38,7 @@ parent_fixture = {
     "name": "Parent",
     "properties": {
         "name": {"type": "string"},
-        "children": {"type": "array", "items": [{"type": "object"}]},
+        "children": {"type": "array", "items": {"type": "object"}},
     },
     "required": ["name", "children"],
 }
diff --git a/tox.ini b/tox.ini
index 928be3b..f38885d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,8 +3,9 @@ skipsdist = True
 envlist = py35,py36,py37,py38
 
 [testenv]
-whitelist_externals = poetry
 skip_install = true
+deps =
+  poetry
 commands =
   poetry install -v
   poetry run pytest