feat: ad PyRuntimeInfo.abi_flags

Author: rickeylev

CHANGELOG.md

@@ -51,6 +51,8 @@ A brief description of the categories of changes:
 * (toolchain) Support for freethreaded Python toolchains is now available. Use
   the config flag `//python/config_settings:py_freethreaded` to toggle the
   selection of the free-threaded toolchains.
+* (toolchain) {obj}`py_runtime.abi_flags` attribute and
+  {obj}`PyRuntimeInfo.abi_flags` field added.
 
 {#v0-0-0-removed}
 ### Removed

python/private/py_runtime_info.bzl

@@ -67,7 +67,8 @@ def _PyRuntimeInfo_init(
         bootstrap_template = None,
         interpreter_version_info = None,
         stage2_bootstrap_template = None,
-        zip_main_template = None):
+        zip_main_template = None,
+        abi_flags = ""):
     if (interpreter_path and interpreter) or (not interpreter_path and not interpreter):
         fail("exactly one of interpreter or interpreter_path must be specified")
 
@@ -105,6 +106,7 @@ def _PyRuntimeInfo_init(
         stub_shebang = DEFAULT_STUB_SHEBANG
 
     return {
+        "abi_flags": abi_flags,
         "bootstrap_template": bootstrap_template,
         "coverage_files": coverage_files,
         "coverage_tool": coverage_tool,
@@ -133,6 +135,11 @@ the same conventions as the standard CPython interpreter.
 """,
     init = _PyRuntimeInfo_init,
     fields = {
+        "abi_flags": """
+:type: str
+
+The runtime's ABI flags, i.e. `sys.abiflags`.
+""",
         "bootstrap_template": """
 :type: File
 

python/private/py_runtime_rule.bzl

@@ -101,6 +101,13 @@ def _py_runtime_impl(ctx):
             interpreter_version_info["minor"],
         )
 
+    abi_flags = ctx.attr.abi_flags
+    if abi_flags == "<AUTO>":
+        abi_flags = ""
+        if ctx.attr._py_freethreaded_flag[BuildSettingInfo].value == FreeThreadedFlag.YES:
+            abi_flags += "t"
+
+    # Args common to both BuiltinPyRuntimeInfo and PyRuntimeInfo
     py_runtime_info_kwargs = dict(
         interpreter_path = interpreter_path or None,
         interpreter = interpreter,
@@ -120,6 +127,7 @@ def _py_runtime_impl(ctx):
         pyc_tag = pyc_tag,
         stage2_bootstrap_template = ctx.file.stage2_bootstrap_template,
         zip_main_template = ctx.file.zip_main_template,
+        abi_flags = abi_flags,
     ))
 
     if not IS_BAZEL_7_OR_HIGHER:
@@ -179,6 +187,14 @@ py_runtime(
 """,
     fragments = ["py"],
     attrs = dicts.add(NATIVE_RULES_ALLOWLIST_ATTRS, {
+        "abi_flags": attr.string(
+            default = "<AUTO>",
+            doc = """
+The runtime's ABI flags, i.e. `sys.abiflags`.
+
+If not set, then it will be set based on flags.
+""",
+        ),
         "bootstrap_template": attr.label(
             allow_single_file = True,
             default = DEFAULT_BOOTSTRAP_TEMPLATE,
@@ -335,6 +351,9 @@ The {obj}`PyRuntimeInfo.zip_main_template` field.
 :::
 """,
         ),
+        "_py_freethreaded_flag": attr.label(
+            default = "//python/config_settings:py_freethreaded",
+        ),
         "_python_version_flag": attr.label(
             default = "//python/config_settings:python_version",
         ),