diff --git a/poethepoet/app.py b/poethepoet/app.py
index fe83b72d..2b5577c3 100644
--- a/poethepoet/app.py
+++ b/poethepoet/app.py
@@ -90,12 +90,11 @@ def resolve_task(self) -> bool:
         return True
 
     def run_task(self, context: Optional[RunContext] = None) -> Optional[int]:
-        _, *extra_args = self.ui["task"]
         if context is None:
             context = self.get_run_context()
         try:
             assert self.task
-            return self.task.run(context=context, extra_args=extra_args)
+            return self.task.run(context=context, extra_args=self.ui["task"][1:])
         except PoeException as error:
             self.print_help(error=error)
             return 1
diff --git a/poethepoet/task/script.py b/poethepoet/task/script.py
index 710b1018..3b28e8d1 100644
--- a/poethepoet/task/script.py
+++ b/poethepoet/task/script.py
@@ -1,4 +1,5 @@
 import ast
+import re
 from typing import (
     Any,
     Dict,
@@ -104,7 +105,12 @@ def parse_script_content(self, args: Optional[Dict[str, Any]]) -> Tuple[str, str
                 return target_module, f"{target_ref}(**({args}))"
             return target_module, f"{target_ref}()"
 
-        return target_module, resolve_function_call(target_ref, set(args or tuple()))
+        function_call = resolve_function_call(target_ref, set(args or tuple()))
+        # Strip out any new lines because they can be problematic on windows
+        function_call = re.sub(r"((\r\n|\r|\n) | (\r\n|\r|\n))", " ", function_call)
+        function_call = re.sub(r"(\r\n|\r|\n)", " ", function_call)
+
+        return target_module, function_call
 
     @staticmethod
     def format_args_class(
@@ -117,7 +123,7 @@ def format_args_class(
         if named_args is None:
             return ""
         return (
-            f'__args=type("{classname}",(object,),'
+            f'{classname}=type("{classname}",(object,),'
             "{"
             + ",".join(f"{name!r}:{value!r}" for name, value in named_args.items())
             + "});"
diff --git a/poethepoet/virtualenv.py b/poethepoet/virtualenv.py
index fe283379..cac23622 100644
--- a/poethepoet/virtualenv.py
+++ b/poethepoet/virtualenv.py
@@ -30,12 +30,13 @@ def resolve_executable(self, executable: str) -> str:
         bin_dir = self.bin_dir()
         if bin_dir.joinpath(executable).is_file():
             return str(bin_dir.joinpath(executable))
-        if (
-            self._is_windows
-            and not executable.endswith(".exe")
-            and bin_dir.joinpath(f"{executable}.exe").is_file()
-        ):
-            return str(bin_dir.joinpath(f"{executable}.exe"))
+        if self._is_windows:
+            if bin_dir.joinpath(f"{executable}.com").is_file():
+                return str(bin_dir.joinpath(f"{executable}.com"))
+            if bin_dir.joinpath(f"{executable}.exe").is_file():
+                return str(bin_dir.joinpath(f"{executable}.exe"))
+            if bin_dir.joinpath(f"{executable}.bat").is_file():
+                return str(bin_dir.joinpath(f"{executable}.bat"))
         return executable
 
     @staticmethod
diff --git a/pyproject.toml b/pyproject.toml
index ab33ab8e..55584e6b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,6 +55,7 @@ poethepoet = "poethepoet.plugin:PoetryPlugin"
            htmlcov
            ./tests/fixtures/simple_project/venv
            ./tests/fixtures/venv_project/myvenv
+           ./tests/fixtures/poetry_plugin_project/**/.venv
            ./tests/temp
   """
 
diff --git a/tests/conftest.py b/tests/conftest.py
index 6d29b39a..f5767f6d 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -207,15 +207,17 @@ def run_poetry(use_venv, poe_project_path):
 
     def run_poetry(args: List[str], cwd: str, env: Optional[Dict[str, str]] = None):
         venv = Virtualenv(venv_location)
+
+        cmd = (venv.resolve_executable("python"), "-m", "poetry", *args)
+        print("Poetry cmd:", cmd[0])
         poetry_proc = Popen(
-            (venv.resolve_executable("poetry"), *args),
+            cmd,
             env=venv.get_env_vars({**os.environ, **(env or {})}),
             stdout=PIPE,
             stderr=PIPE,
             cwd=cwd,
         )
         poetry_out, poetry_err = poetry_proc.communicate()
-
         result = PoeRunResult(
             code=poetry_proc.returncode,
             path=cwd,
@@ -230,9 +232,7 @@ def run_poetry(args: List[str], cwd: str, env: Optional[Dict[str, str]] = None):
         venv_location,
         [
             ".[poetry_plugin]",
-            # TODO: poetry install from a release
-            "./tests/fixtures/packages/poetry-1.2.0b2.dev0-py3-none-any.whl",
-            "--pre",
+            "./tests/fixtures/packages/poetry-1.2.1-py3-none-any.whl",
         ],
         require_empty=True,
     ):
diff --git a/tests/fixtures/packages/cowpy-1.1.5-py3-none-any.whl b/tests/fixtures/packages/cowpy-1.1.5-py3-none-any.whl
new file mode 100644
index 00000000..28d2b34f
Binary files /dev/null and b/tests/fixtures/packages/cowpy-1.1.5-py3-none-any.whl differ
diff --git a/tests/fixtures/packages/poetry-1.2.0b2.dev0-py3-none-any.whl b/tests/fixtures/packages/poetry-1.2.0b2.dev0-py3-none-any.whl
deleted file mode 100644
index c3298042..00000000
Binary files a/tests/fixtures/packages/poetry-1.2.0b2.dev0-py3-none-any.whl and /dev/null differ
diff --git a/tests/fixtures/packages/poetry-1.2.1-py3-none-any.whl b/tests/fixtures/packages/poetry-1.2.1-py3-none-any.whl
new file mode 100644
index 00000000..d8f3d614
Binary files /dev/null and b/tests/fixtures/packages/poetry-1.2.1-py3-none-any.whl differ
diff --git a/tests/fixtures/packages/python_cowsay-1.0.1-py3-none-any.whl b/tests/fixtures/packages/python_cowsay-1.0.1-py3-none-any.whl
deleted file mode 100644
index 4fa02334..00000000
Binary files a/tests/fixtures/packages/python_cowsay-1.0.1-py3-none-any.whl and /dev/null differ
diff --git a/tests/fixtures/poetry_plugin_project/deps/cowsay-4.0-py2.py3-none-any.whl b/tests/fixtures/poetry_plugin_project/deps/cowsay-4.0-py2.py3-none-any.whl
deleted file mode 100644
index 17c9c1e1..00000000
Binary files a/tests/fixtures/poetry_plugin_project/deps/cowsay-4.0-py2.py3-none-any.whl and /dev/null differ
diff --git a/tests/fixtures/poetry_plugin_project/deps/poetry-1.2.0b2.dev0-py3-none-any.whl b/tests/fixtures/poetry_plugin_project/deps/poetry-1.2.0b2.dev0-py3-none-any.whl
deleted file mode 100644
index 85e2effe..00000000
Binary files a/tests/fixtures/poetry_plugin_project/deps/poetry-1.2.0b2.dev0-py3-none-any.whl and /dev/null differ
diff --git a/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.lock b/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.lock
new file mode 100644
index 00000000..db62ca3f
--- /dev/null
+++ b/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.lock
@@ -0,0 +1,35 @@
+[[package]]
+name = "cowpy"
+version = "1.1.5"
+description = ""
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.source]
+type = "file"
+url = "../../packages/cowpy-1.1.5-py3-none-any.whl"
+
+[[package]]
+name = "poe-test-helpers"
+version = "0.2.0"
+description = "Provides cross platform executables to help with testing"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+develop = false
+
+[package.source]
+type = "directory"
+url = "../../packages/poe_test_helpers"
+
+[metadata]
+lock-version = "1.1"
+python-versions = "^3.7"
+content-hash = "94002636f413787b5c4816f3f896ec98cd57abc7c8a9bb8e084a4af1eb6d551c"
+
+[metadata.files]
+cowpy = [
+    {file = "cowpy-1.1.5-py3-none-any.whl", hash = "sha256:de5ae7646dd30b4936013666c6bd019af9cf411cc3b377c8538cfd8414262921"},
+]
+poe-test-helpers = []
diff --git a/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.toml b/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.toml
new file mode 100644
index 00000000..ab1033bd
--- /dev/null
+++ b/tests/fixtures/poetry_plugin_project/empty_prefix/poetry.toml
@@ -0,0 +1,2 @@
+[virtualenvs]
+in-project = true
diff --git a/tests/fixtures/poetry_plugin_project/empty_prefix/pyproject.toml b/tests/fixtures/poetry_plugin_project/empty_prefix/pyproject.toml
index 9dd7d00f..3d1cab9d 100644
--- a/tests/fixtures/poetry_plugin_project/empty_prefix/pyproject.toml
+++ b/tests/fixtures/poetry_plugin_project/empty_prefix/pyproject.toml
@@ -8,14 +8,15 @@ authors     = ["Nat Noordanus <n@natn.me>"]
 python = "^3.7"
 
 [tool.poetry.dev-dependencies]
-cowsay = "../../packages/python_cowsay-1.0.1-py3-none-any.whl"
+cowpy = { path = "../../packages/cowpy-1.1.5-py3-none-any.whl" }
+poe_test_helpers = { path = "../../packages/poe_test_helpers" }
 
 [tool.poe]
 poetry_command = ""
 
 [tool.poe.tasks]
 echo = { cmd = "poe_test_echo", help = "It's like echo"}
-cow-greet = "cowsay 'good day sir!'"
+cow-greet = "cowpy 'good day sir!'"
 
 [build-system]
 requires      = ["poetry-core"]
diff --git a/tests/fixtures/poetry_plugin_project/poetry.lock b/tests/fixtures/poetry_plugin_project/poetry.lock
index 531892f6..8ac48613 100644
--- a/tests/fixtures/poetry_plugin_project/poetry.lock
+++ b/tests/fixtures/poetry_plugin_project/poetry.lock
@@ -1,18 +1,35 @@
 [[package]]
-name = "cowsay"
-version = "4.0"
-description = "The famous cowsay for GNU/Linux is now available for python"
+name = "cowpy"
+version = "1.1.5"
+description = ""
 category = "dev"
 optional = false
-python-versions = "*"
+python-versions = ">=3.6"
+
+[package.source]
+type = "file"
+url = "../packages/cowpy-1.1.5-py3-none-any.whl"
+
+[[package]]
+name = "poe-test-helpers"
+version = "0.2.0"
+description = "Provides cross platform executables to help with testing"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+develop = false
+
+[package.source]
+type = "directory"
+url = "../packages/poe_test_helpers"
 
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "2d0a2b1a347aadbadc1ac311b3a6fb22222d61d1bc110deaf3b3321a0bd15413"
+content-hash = "5fa24f3ca30fc90015b8a3d1b0ba6b99711a860a945dce08a64dc9c06dc35c59"
 
 [metadata.files]
-cowsay = [
-    {file = "cowsay-4.0-py2.py3-none-any.whl", hash = "sha256:2594b11d6624fff4bf5147b6bdd510ada54a7b5b4e3f2b15ac2a6d3cf99e0bf8"},
-    {file = "cowsay-4.0.tar.gz", hash = "sha256:a9e1e5f957054010b7faa6406deb5f6aa5cb674498118bbbed0151f92c2dc20e"},
+cowpy = [
+    {file = "cowpy-1.1.5-py3-none-any.whl", hash = "sha256:de5ae7646dd30b4936013666c6bd019af9cf411cc3b377c8538cfd8414262921"},
 ]
+poe-test-helpers = []
diff --git a/tests/fixtures/poetry_plugin_project/pyproject.toml b/tests/fixtures/poetry_plugin_project/pyproject.toml
index 3a32b53d..7fe5f3c3 100644
--- a/tests/fixtures/poetry_plugin_project/pyproject.toml
+++ b/tests/fixtures/poetry_plugin_project/pyproject.toml
@@ -8,7 +8,8 @@ authors     = ["Nat Noordanus <n@natn.me>"]
 python = "^3.7"
 
 [tool.poetry.dev-dependencies]
-cowsay = "../packages/python_cowsay-1.0.1-py3-none-any.whl"
+cowpy = { path = "../packages/cowpy-1.1.5-py3-none-any.whl" }
+poe_test_helpers = { path = "../packages/poe_test_helpers" }
 
 [tool.poe.poetry_hooks]
 pre_env_info = "echo 'THIS IS YOUR ENV!'"
@@ -16,8 +17,8 @@ post_env_info = "echo 'THAT WAS YOUR ENV!'"
 
 [tool.poe.tasks]
 echo = { cmd = "poe_test_echo", help = "It's like echo"}
-cow-greet = "cowsay 'good day sir!'"
-cow-cheese.shell = "import cowsay; print(list(cowsay.char_names)[1])"
+cow-greet = "cowpy" # Passing args to cowpy doesn't work with subprocess
+cow-cheese.shell = "from cowpy import cow; print(list(cow.COWACTERS)[5])"
 cow-cheese.interpreter = "python"
 
 [build-system]
diff --git a/tests/test_poetry_plugin.py b/tests/test_poetry_plugin.py
index 0543c1a6..fd3ed85e 100644
--- a/tests/test_poetry_plugin.py
+++ b/tests/test_poetry_plugin.py
@@ -5,13 +5,14 @@
 
 @pytest.fixture(scope="session")
 def setup_poetry_project(run_poetry, projects):
-    run_poetry(
-        ["config", "--local", "virtualenvs.in-project", "true"],
-        cwd=projects["poetry_plugin"],
-    )
     run_poetry(["install"], cwd=projects["poetry_plugin"])
 
 
+@pytest.fixture(scope="session")
+def setup_poetry_project_empty_prefix(run_poetry, projects):
+    run_poetry(["install"], cwd=projects["poetry_plugin/empty_prefix"].parent)
+
+
 @pytest.mark.slow
 @pytest.mark.skipif(version_info < (3, 7), reason="dependencies require python>=3.7")
 def test_poetry_help(run_poetry, projects):
@@ -27,13 +28,20 @@ def test_poetry_help(run_poetry, projects):
 def test_task_with_cli_dependency(
     run_poetry, projects, setup_poetry_project, is_windows
 ):
-    result = run_poetry(["poe", "cow-greet"], cwd=projects["poetry_plugin"])
+    result = run_poetry(
+        ["poe", "cow-greet", "yo yo yo"],
+        cwd=projects["poetry_plugin"],
+    )
     if is_windows:
-        assert result.stdout.startswith("Poe => cowsay 'good day sir!'")
-        assert "| 'good day sir!' |" in result.stdout
+        assert result.stdout.startswith("Poe => cowpy yo yo yo")
+        assert "< yo yo yo >" in result.stdout
     else:
-        assert result.stdout.startswith("Poe => cowsay good day sir!")
-        assert "| good day sir! |" in result.stdout
+        # On POSIX cowpy expects notices its being called as a subprocess and tries
+        # unproductively to take input from stdin
+        assert result.stdout.startswith("Poe => cowpy yo yo yo")
+        assert (
+            "< Cowacter, eyes:default, tongue:False, thoughts:False >" in result.stdout
+        )
     # assert result.stderr == ""
 
 
@@ -44,7 +52,7 @@ def test_task_with_lib_dependency(
 ):
     result = run_poetry(["poe", "cow-cheese"], cwd=projects["poetry_plugin"])
     assert result.stdout == (
-        "Poe => import cowsay; print(list(cowsay.char_names)[1])\ncheese\n"
+        "Poe => from cowpy import cow; print(list(cow.COWACTERS)[5])\ncheese\n"
     )
     # assert result.stderr == ""
 
@@ -65,7 +73,7 @@ def test_task_accepts_any_args(run_poetry, projects, setup_poetry_project):
 @pytest.mark.slow
 @pytest.mark.skipif(version_info < (3, 7), reason="dependencies require python>=3.7")
 def test_poetry_help_without_poe_command_prefix(
-    run_poetry, projects, setup_poetry_project
+    run_poetry, projects, setup_poetry_project_empty_prefix
 ):
     result = run_poetry([], cwd=projects["poetry_plugin/empty_prefix"].parent)
     assert result.stdout.startswith("Poetry (version ")
@@ -77,7 +85,7 @@ def test_poetry_help_without_poe_command_prefix(
 @pytest.mark.slow
 @pytest.mark.skipif(version_info < (3, 7), reason="dependencies require python>=3.7")
 def test_running_tasks_without_poe_command_prefix(
-    run_poetry, projects, setup_poetry_project
+    run_poetry, projects, setup_poetry_project_empty_prefix
 ):
     result = run_poetry(
         ["echo", "--lol=:D", "--version", "--help"],