feat: collect Python toolchain information via instrument hooks environment API

src/pytest_codspeed/instruments/analysis.py

@@ -33,6 +33,7 @@ def __init__(self, config: CodSpeedConfig, mode: MeasurementMode) -> None:
         try:
             self.instrument_hooks = InstrumentHooks()
             self.instrument_hooks.set_integration("pytest-codspeed", __semver_version__)
+            self.instrument_hooks.collect_and_write_python_environment()
         except RuntimeError as e:
             if os.environ.get("CODSPEED_ENV") is not None:
                 raise Exception(

src/pytest_codspeed/instruments/hooks/__init__.py

@@ -2,6 +2,7 @@
 
 import os
 import sys
+import sysconfig
 import warnings
 from typing import TYPE_CHECKING
 
@@ -92,3 +93,43 @@ def set_feature(self, feature: int, enabled: bool) -> None:
             enabled: Whether to enable or disable the feature
         """
         self.lib.instrument_hooks_set_feature(feature, enabled)
+
+    def set_environment(self, section_name: str, key: str, value: str) -> None:
+        """Register a key-value pair under a named section for environment collection.
+
+        Args:
+            section_name: The section name (e.g. "Python")
+            key: The key (e.g. "version")
+            value: The value (e.g. "3.13.12")
+        """
+        ret = self.lib.instrument_hooks_set_environment(
+            self.instance,
+            section_name.encode("utf-8"),
+            key.encode("utf-8"),
+            value.encode("utf-8"),
+        )
+        if ret != 0:
+            warnings.warn("Failed to set environment data", RuntimeWarning)
+
+    def write_environment(self, pid: int | None = None) -> None:
+        """Flush all registered environment sections to disk.
+
+        Writes to $CODSPEED_PROFILE_FOLDER/environment-<pid>.json.
+
+        Args:
+            pid: Optional process ID (defaults to current process)
+        """
+        if pid is None:
+            pid = os.getpid()
+        ret = self.lib.instrument_hooks_write_environment(self.instance, pid)
+        if ret != 0:
+            warnings.warn("Failed to write environment data", RuntimeWarning)
+
+    def collect_and_write_python_environment(self) -> None:
+        """Collect Python toolchain information and write it to disk."""
+
+        for key, value in sysconfig.get_config_vars().items():
+            self.set_environment(
+                "python", f"{key}", str(value) if value is not None else ""
+            )
+        self.write_environment()

src/pytest_codspeed/instruments/hooks/build.py

@@ -36,6 +36,10 @@
 void callgrind_stop_instrumentation();
 
 void instrument_hooks_set_feature(uint64_t feature, bool enabled);
+
+uint8_t instrument_hooks_set_environment(InstrumentHooks *, const char *section_name,
+                                         const char *key, const char *value);
+uint8_t instrument_hooks_write_environment(InstrumentHooks *, uint32_t pid);
 """)
 
 ffibuilder.set_source(
@@ -47,6 +51,8 @@
         "src/pytest_codspeed/instruments/hooks/instrument-hooks/dist/core.c",
     ],
     include_dirs=[str(includes_dir)],
+    # IMPORTANT: Keep in sync with instrument-hooks/ci.yml (COMMON_CFLAGS)
+    extra_compile_args=["-Wno-format-security"],
 )
 
 if __name__ == "__main__":

src/pytest_codspeed/instruments/hooks/dist_instrument_hooks.pyi

@@ -31,5 +31,13 @@ class lib:
     def callgrind_stop_instrumentation() -> int: ...
     @staticmethod
     def instrument_hooks_set_feature(feature: int, enabled: bool) -> None: ...
+    @staticmethod
+    def instrument_hooks_set_environment(
+        hooks: InstrumentHooksPointer, section_name: bytes, key: bytes, value: bytes
+    ) -> int: ...
+    @staticmethod
+    def instrument_hooks_write_environment(
+        hooks: InstrumentHooksPointer, pid: int
+    ) -> int: ...
 
 LibType = type[lib]

src/pytest_codspeed/instruments/walltime.py

@@ -163,6 +163,7 @@ def __init__(self, config: CodSpeedConfig, _mode: MeasurementMode) -> None:
         try:
             self.instrument_hooks = InstrumentHooks()
             self.instrument_hooks.set_integration("pytest-codspeed", __semver_version__)
+            self.instrument_hooks.collect_and_write_python_environment()
         except RuntimeError as e:
             if os.environ.get("CODSPEED_ENV") is not None:
                 warnings.warn(