allow Paths in save()

altair_saver/_utils.py

@@ -2,6 +2,7 @@
 from http import client
 import io
 import os
+import pathlib
 import socket
 import subprocess
 import sys
@@ -133,9 +134,10 @@ def temporary_filename(
 
 
 @contextlib.contextmanager
-def maybe_open(fp: Union[IO, str], mode: str = "w") -> Iterator[IO]:
-    """Context manager to write to a file specified by filename or file-like object"""
-    if isinstance(fp, str):
+def maybe_open(fp: Union[IO, str, pathlib.PurePath], mode: str = "w") -> Iterator[IO]:
+    """Context manager to write to a file specified by filename, Path or
+    file-like object"""
+    if isinstance(fp, str) or isinstance(fp, pathlib.PurePath):
         with open(fp, mode) as f:
             yield f
     elif isinstance(fp, io.TextIOBase) and "b" in mode:
@@ -150,11 +152,13 @@ def maybe_open(fp: Union[IO, str], mode: str = "w") -> Iterator[IO]:
         yield fp
 
 
-def extract_format(fp: Union[IO, str]) -> str:
-    """Extract the altair_saver output format from a file or filename."""
+def extract_format(fp: Union[IO, str, pathlib.PurePath]) -> str:
+    """Extract the altair_saver output format from a file, filename or Path."""
     filename: Optional[str]
     if isinstance(fp, str):
         filename = fp
+    elif isinstance(fp, pathlib.PurePath):
+        filename = str(fp)
     else:
         filename = getattr(fp, "name", None)
     if filename is None:

altair_saver/savers/_selenium.py

@@ -215,11 +215,16 @@ def _serve(cls, content: str, js_resources: Dict[str, str]) -> str:
         if cls._provider is None:
             cls._provider = Provider()
         resource = cls._provider.create(
-            content=content, route="", headers={"Access-Control-Allow-Origin": "*"},
+            content=content,
+            route="",
+            headers={"Access-Control-Allow-Origin": "*"},
         )
         cls._resources[resource.url] = resource
         for route, content in js_resources.items():
-            cls._resources[route] = cls._provider.create(content=content, route=route,)
+            cls._resources[route] = cls._provider.create(
+                content=content,
+                route=route,
+            )
         return resource.url
 
     @classmethod

altair_saver/savers/tests/test_html.py

@@ -75,7 +75,9 @@ def test_html_save(
 @pytest.mark.parametrize("embed_options", [None, {"theme": "dark"}])
 @pytest.mark.parametrize("case, data", get_testcases())
 def test_html_mimebundle(
-    case: str, data: Dict[str, Any], embed_options: Optional[dict],
+    case: str,
+    data: Dict[str, Any],
+    embed_options: Optional[dict],
 ) -> None:
     saver = HTMLSaver(data["vega-lite"], embed_options=embed_options)
     bundle = saver.mimebundle("html")

altair_saver/savers/tests/test_node.py

@@ -112,7 +112,9 @@ def exec_path(name: str) -> str:
 
 @pytest.mark.parametrize("suppress_warnings", [True, False])
 def test_stderr_suppression(
-    interactive_spec: JSONDict, suppress_warnings: bool, capsys: SysCapture,
+    interactive_spec: JSONDict,
+    suppress_warnings: bool,
+    capsys: SysCapture,
 ) -> None:
     message = "WARN Can not resolve event source: window"
 

altair_saver/tests/test_utils.py

@@ -1,5 +1,6 @@
 import http
 import io
+import pathlib
 import socket
 import subprocess
 import tempfile
@@ -43,32 +44,39 @@ def request(*args: Any, **kwargs: Any) -> None:
         ("vl.json", "vega-lite"),
     ],
 )
-@pytest.mark.parametrize("use_filename", [True, False])
-def test_extract_format(ext: str, fmt: str, use_filename: bool) -> None:
-    if use_filename:
+@pytest.mark.parametrize("fp_type", ["string", "path", "pointer", "stream"])
+def test_extract_format(ext: str, fmt: str, fp_type: str) -> None:
+    if fp_type == "string":
         filename = f"chart.{ext}"
         assert extract_format(filename) == fmt
-    else:
+    elif fp_type == "path":
+        filepath = pathlib.Path(f"chart.{ext}")
+        assert extract_format(filepath) == fmt
+    elif fp_type == "pointer":
         with tempfile.NamedTemporaryFile(suffix=f".{ext}") as fp:
             assert extract_format(fp) == fmt
-
-
-def test_extract_format_failure() -> None:
-    fp = io.StringIO()
-    with pytest.raises(ValueError) as err:
-        extract_format(fp)
-    assert f"Cannot infer format from {fp}" in str(err.value)
+    elif fp_type == "stream":
+        string_io = io.StringIO()
+        with pytest.raises(ValueError) as err:
+            extract_format(string_io)
+        assert f"Cannot infer format from {string_io}" in str(err.value)
 
 
 @pytest.mark.parametrize("mode", ["w", "wb"])
-def test_maybe_open_filename(mode: str) -> None:
-    content_raw = "testing maybe_open with filename\n"
+@pytest.mark.parametrize("fp_type", ["string", "path"])
+def test_maybe_open_filename(mode: str, fp_type: str) -> None:
+    content_raw = "testing maybe_open with filename or path\n"
     content = content_raw.encode() if "b" in mode else content_raw
 
     with temporary_filename() as filename:
-        with maybe_open(filename, mode) as f:
+        if fp_type == "path":
+            fp = pathlib.Path(filename)
+        elif fp_type == "string":
+            fp = filename
+
+        with maybe_open(fp, mode) as f:
             f.write(content)
-        with open(filename, "rb" if "b" in mode else "r") as f:
+        with open(fp, "rb" if "b" in mode else "r") as f:
             assert f.read() == content