Improve the new command

poetry/console/commands/new.py

@@ -19,6 +19,7 @@ class NewCommand(Command):
 
 
     def handle(self):
     def handle(self):
         from poetry.layouts import layout
         from poetry.layouts import layout
+        from poetry.semver import parse_constraint
         from poetry.utils._compat import Path
         from poetry.utils._compat import Path
         from poetry.utils.env import SystemEnv
         from poetry.utils.env import SystemEnv
         from poetry.vcs.git import GitConfig
         from poetry.vcs.git import GitConfig
@@ -55,12 +56,21 @@ class NewCommand(Command):
         default_python = "^{}".format(
         default_python = "^{}".format(
             ".".join(str(v) for v in current_env.version_info[:2])
             ".".join(str(v) for v in current_env.version_info[:2])
         )
         )
+
+        dev_dependencies = {}
+        python_constraint = parse_constraint(default_python)
+        if parse_constraint("<3.5").allows_any(python_constraint):
+            dev_dependencies["pytest"] = "^4.6"
+        if parse_constraint(">=3.5").allows_all(python_constraint):
+            dev_dependencies["pytest"] = "^5.2"
+
         layout_ = layout_(
         layout_ = layout_(
             name,
             name,
             "0.1.0",
             "0.1.0",
             author=author,
             author=author,
             readme_format=readme_format,
             readme_format=readme_format,
             python=default_python,
             python=default_python,
+            dev_dependencies=dev_dependencies,
         )
         )
         layout_.create(path)
         layout_.create(path)
 
 

poetry/layouts/layout.py

@@ -63,10 +63,7 @@ class Layout(object):
         self._license = license
         self._license = license
         self._python = python
         self._python = python
         self._dependencies = dependencies or {}
         self._dependencies = dependencies or {}
-        if dev_dependencies is None:
-            dev_dependencies = {"pytest": "^3.5"}
-
-        self._dev_dependencies = dev_dependencies
+        self._dev_dependencies = dev_dependencies or {}
 
 
         if not author:
         if not author:
             author = "Your Name <you@example.com>"
             author = "Your Name <you@example.com>"
@@ -131,8 +128,6 @@ class Layout(object):
         readme_file.touch()
         readme_file.touch()
 
 
     def _create_tests(self, path):
     def _create_tests(self, path):
-        self._dev_dependencies["pytest"] = "^3.0"
-
         tests = path / "tests"
         tests = path / "tests"
         tests_init = tests / "__init__.py"
         tests_init = tests / "__init__.py"
         tests_default = tests / "test_{}.py".format(self._package_name)
         tests_default = tests / "test_{}.py".format(self._package_name)