tags: add interpreter_abi

Signed-off-by: Filipe Laíns <lains@riseup.net>

packaging/tags.py

@@ -484,6 +484,12 @@ def _version_nodot(version: PythonVersion) -> str:
     return "".join(map(str, version))
 
 
+def interpreter_abi() -> str:
+    if interpreter_name() == "cp":
+        return _cpython_abis(sys.version_info[:2])[0]
+    return next(_generic_abi())
+
+
 def sys_tags(*, warn: bool = False) -> Iterator[Tag]:
     """
     Returns the sequence of tag triples for the running interpreter.

tests/test_tags.py

@@ -1239,3 +1239,16 @@ def test_cpython_first_none_any_tag(self, monkeypatch):
 
         interpreter = f"cp{tags.interpreter_version()}"
         assert tag == tags.Tag(interpreter, "none", "any")
+
+
+def test_interpreter_abi(monkeypatch):
+    monkeypatch.setattr(tags, "interpreter_name", lambda: "pp")
+    monkeypatch.setattr(
+        sysconfig, "get_config_var", {"SOABI": "pypy39-pp73"}.__getitem__
+    )
+    assert tags.interpreter_abi() == "pypy39_pp73"
+
+    config = {"Py_DEBUG": 0, "WITH_PYMALLOC": 0, "Py_UNICODE_SIZE": 2}
+    monkeypatch.setattr(sysconfig, "get_config_var", config.__getitem__)
+    monkeypatch.setattr(tags, "interpreter_name", lambda: "cp")
+    assert tags.interpreter_abi() == f"cp{sys.version_info.major}{sys.version_info.minor}"