Replace Pystache with Chevron. (#57)

* Relace Pystache with Chevron.

* Don't pin chevron version.

* Add unit test for render_template().

Author: brunns

pytest_mypy_plugins/collect.py

@@ -4,7 +4,6 @@
 import tempfile
 from typing import TYPE_CHECKING, Any, Dict, Iterator, List, Mapping, Optional
 
-import pystache
 import pytest
 import yaml
 from _pytest.config.argparsing import Parser
@@ -99,7 +98,8 @@ def collect(self) -> Iterator["YamlTestItem"]:
                     test_name_suffix = ""
 
                 test_name = f"{test_name_prefix}{test_name_suffix}"
-                main_file = File(path="main.py", content=pystache.render(raw_test["main"], params))
+                main_content = utils.render_template(template=raw_test["main"], data=params)
+                main_file = File(path="main.py", content=main_content)
                 test_files = [main_file] + parse_test_files(raw_test.get("files", []))
                 expect_fail = raw_test.get("expect_fail", False)
                 regex = raw_test.get("regex", False)

pytest_mypy_plugins/tests/test_utils.py

@@ -0,0 +1,14 @@
+# encoding=utf-8
+from pytest_mypy_plugins import utils
+
+
+def test_render_template_with_None_value() -> None:
+    # Given
+    template = "{{ a }} {{ b }}"
+    data = {"a": None, "b": 99}
+
+    # When
+    actual = utils.render_template(template=template, data=data)
+
+    # Then
+    assert actual == "None 99"

pytest_mypy_plugins/utils.py

@@ -19,7 +19,7 @@
     Union,
 )
 
-import pystache
+import chevron
 import regex
 from decorator import contextmanager
 
@@ -341,7 +341,8 @@ def extract_output_matchers_from_out(out: str, params: Mapping[str, Any], regex:
     The result is a list of output matchers
     """
     matchers = []
-    for line in pystache.render(out, params).split("\n"):
+    lines = render_template(out, params).split("\n")
+    for line in lines:
         match = re.search(
             r"^(?P<fname>.*):(?P<lnum>\d*): (?P<severity>.*):((?P<col>\d+):)? (?P<message>.*)$", line.strip()
         )
@@ -368,6 +369,10 @@ def extract_output_matchers_from_out(out: str, params: Mapping[str, Any], regex:
     return matchers
 
 
+def render_template(template: str, data: Mapping[str, Any]) -> str:
+    return chevron.render(template=template, data={k: v if v is not None else "None" for k, v in data.items()})
+
+
 def get_func_first_lnum(attr: Callable[..., None]) -> Optional[Tuple[int, List[str]]]:
     lines, _ = inspect.getsourcelines(attr)
     for lnum, line in enumerate(lines):

setup.py

@@ -8,7 +8,7 @@
     "mypy>=0.790",
     "decorator",
     "pyyaml",
-    "pystache>=0.5.4",
+    "chevron",
 ]
 
 setup(