Add a global manager for configuring runtimes

pytest_pyodide/__init__.py

@@ -1,5 +1,6 @@
 from importlib.metadata import PackageNotFoundError, version
 
+from .config import get_global_config
 from .decorator import copy_files_to_pyodide, run_in_pyodide
 from .runner import (
     NodeRunner,
@@ -30,4 +31,5 @@
     "run_in_pyodide",
     "copy_files_to_pyodide",
     "spawn_web_server",
+    "get_global_config",
 ]

pytest_pyodide/config.py

@@ -0,0 +1,61 @@
+"""
+Stores the global runtime configuration related to the pytest_pyodide package.
+"""
+
+from typing import Literal
+
+RUNTIMES = Literal["chrome", "firefox", "node", "safari"]
+
+_global_load_pyodide_script = """
+let pyodide = await loadPyodide({ fullStdLib: false, jsglobals : self });
+"""
+
+
+class Config:
+    def __init__(self):
+        # Flags to be passed to the browser or runtime.
+        self.flags: dict[RUNTIMES, list[str]] = {
+            "chrome": ["--js-flags=--expose-gc"],
+            "firefox": [],
+            "node": [],
+            "safari": [],
+        }
+
+        # The script to be executed to load the Pyodide.
+        self.load_pyodide_script: dict[RUNTIMES, str] = {
+            "chrome": _global_load_pyodide_script,
+            "firefox": _global_load_pyodide_script,
+            "node": _global_load_pyodide_script,
+            "safari": _global_load_pyodide_script,
+        }
+
+        # The script to be executed to initialize the runtime.
+        self.initialize_script: str = "pyodide.runPython('');"
+
+    def set_flag(self, runtime: RUNTIMES, flags: list[str]):
+        self.flags[runtime] = flags
+
+    def get_flag(self, runtime: RUNTIMES) -> list[str]:
+        return self.flags[runtime]
+
+    def set_load_pyodide_script(self, runtime: RUNTIMES, load_pyodide_script: str):
+        self.load_pyodide_script[runtime] = load_pyodide_script
+
+    def get_load_pyodide_script(self, runtime: RUNTIMES) -> str:
+        return self.load_pyodide_script[runtime]
+
+    def set_initialize_script(self, initialize_script: str):
+        self.initialize_script = initialize_script
+
+    def get_initialize_script(self) -> str:
+        return self.initialize_script
+
+
+SINGLETON = Config()
+
+
+def get_global_config() -> Config:
+    """
+    Return the singleton config object.
+    """
+    return SINGLETON

pytest_pyodide/fixture.py

@@ -7,9 +7,8 @@
 
 import pytest
 
+from .config import get_global_config
 from .runner import (
-    CHROME_FLAGS,
-    FIREFOX_FLAGS,
     NodeRunner,
     PlaywrightChromeRunner,
     PlaywrightFirefoxRunner,
@@ -41,13 +40,14 @@ def _playwright_browsers(request):
             )
 
         runtimes = pytest.pyodide_runtimes
+        cfg = get_global_config()
 
         with sync_playwright() as p:
             browsers: dict[str, Any] = {}
             supported_browsers: dict[str, tuple[str, list[str]]] = {
                 # browser name: (attr_name, flags)
-                "firefox": ("firefox", FIREFOX_FLAGS),
-                "chrome": ("chromium", CHROME_FLAGS),
+                "firefox": ("firefox", cfg.get_flag("firefox")),
+                "chrome": ("chromium", cfg.get_flag("chrome")),
                 # TODO: enable webkit
                 # "webkit": (),
             }

pytest_pyodide/runner.py

@@ -5,10 +5,7 @@
 import pexpect
 import pytest
 
-CHROME_FLAGS: list[str] = ["--js-flags=--expose-gc"]
-FIREFOX_FLAGS: list[str] = []
-NODE_FLAGS: list[str] = []
-
+from .config import RUNTIMES, get_global_config
 
 TEST_SETUP_CODE = """
 Error.stackTraceLimit = Infinity;
@@ -89,8 +86,6 @@
 };
 """.strip()
 
-INITIALIZE_SCRIPT = "pyodide.runPython('');"
-
 
 class JavascriptException(Exception):
     def __init__(self, msg, stack):
@@ -105,10 +100,17 @@ def __str__(self):
 
 
 class _BrowserBaseRunner:
-    browser = ""
+    browser: RUNTIMES = ""  # type: ignore[assignment]
     script_timeout = 20
     JavascriptException = JavascriptException
 
+    # A common script that runs after pyodide is loaded
+    POST_LOAD_PYODIDE_SCRIPT = """
+    self.pyodide = pyodide;
+    globalThis.pyodide = pyodide;
+    pyodide._api.inTestHoist = true; // improve some error messages for tests
+    """
+
     def __init__(
         self,
         server_port,
@@ -121,13 +123,16 @@ def __init__(
         *args,
         **kwargs,
     ):
+        self._config = get_global_config()
+
         self.server_port = server_port
         self.server_hostname = server_hostname
         self.base_url = f"http://{self.server_hostname}:{self.server_port}"
         self.server_log = server_log
         self.script_type = script_type
         self.dist_dir = dist_dir
         self.driver = self.get_driver(jspi)
+
         self.set_script_timeout(self.script_timeout)
         self.prepare_driver()
         self.javascript_setup()
@@ -171,12 +176,8 @@ def javascript_setup(self):
 
     def load_pyodide(self):
         self.run_js(
-            """
-            let pyodide = await loadPyodide({ fullStdLib: false, jsglobals : self });
-            self.pyodide = pyodide;
-            globalThis.pyodide = pyodide;
-            pyodide._api.inTestHoist = true; // improve some error messages for tests
-            """
+            self._config.get_load_pyodide_script(self.browser)
+            + self.POST_LOAD_PYODIDE_SCRIPT
         )
 
     def initialize_pyodide(self):
@@ -201,7 +202,7 @@ def initialize_pyodide(self):
             }
             """
         )
-        self.run_js(INITIALIZE_SCRIPT)
+        self.run_js(self._config.get_initialize_script())
         from .decorator import initialize_decorator
 
         initialize_decorator(self)
@@ -430,7 +431,7 @@ def get_driver(self, jspi=False):
 
         options = Options()
         options.add_argument("--headless")
-        for flag in FIREFOX_FLAGS:
+        for flag in self._config.get_flag("firefox"):
             options.add_argument(flag)
 
         return Firefox(service=Service(), options=options)
@@ -449,7 +450,7 @@ def get_driver(self, jspi=False):
         if jspi:
             options.add_argument("--enable-features=WebAssemblyExperimentalJSPI")
             options.add_argument("--enable-experimental-webassembly-features")
-        for flag in CHROME_FLAGS:
+        for flag in self._config.get_flag("chrome"):
             options.add_argument(flag)
         return Chrome(options=options)
 
@@ -544,7 +545,7 @@ def init_node(self, jspi=False):
                 f"Node version {node_version} is too old, please use node >= 18"
             )
 
-        extra_args = NODE_FLAGS[:]
+        extra_args = self._config.get_flag("node")[:]
         # Node v14 require the --experimental-wasm-bigint which
         # produces errors on later versions
         if jspi:

tests/test_config.py

@@ -0,0 +1,25 @@
+from pytest_pyodide.config import Config, get_global_config
+
+
+def test_config():
+    c = Config()
+
+    runtimes = ["chrome", "firefox", "node", "safari"]
+
+    for runtime in runtimes:
+        c.get_flag(runtime)
+        c.get_load_pyodide_script(runtime)
+
+        c.set_flag(runtime, ["--headless"])
+        assert c.get_flag(runtime) == ["--headless"]
+
+        c.set_load_pyodide_script(runtime, "console.log('hello')")
+        assert c.get_load_pyodide_script(runtime) == "console.log('hello')"
+
+    c.get_initialize_script()
+    c.set_initialize_script("console.log('hello')")
+    assert c.get_initialize_script() == "console.log('hello')"
+
+
+def test_global_config():
+    assert get_global_config() is get_global_config()