Handle all output file names when building scies. (#2484)

Previously, invoking `pex pex -c pex --venv --scie eager -o pex` to
build the Pex PEX scie would error deep inside the science scie build
process due to the name collision. Since the user has no control over
the lift manifest, this was not able to be corrected.

CHANGES.md

@@ -1,5 +1,14 @@
 # Release Notes
 
+## 2.13.1
+
+This release fixes the `--scie` option to support building a Pex PEX
+scie with something like `pex pex -c pex --venv --scie eager -o pex`.
+Previously, due to the output filename of `pex` colliding with fixed
+internal scie lift manifest file names, this would fail.
+
+* Handle all output file names when building scies. (#2484)
+
 ## 2.13.0
 
 This release improves error message detail when there are failures in

pex/scie/science.py

@@ -70,11 +70,40 @@ def _science_binary_url(suffix=""):
 SCIE_JUMP_VERSION = "1.1.1"
 
 
+@attr.s(frozen=True)
+class Filename(object):
+    name = attr.ib()  # type: str
+
+    @property
+    def placeholder(self):
+        # type: () -> str
+        return "{{{name}}}".format(name=self.name)
+
+
+@attr.s(frozen=True)
+class Filenames(object):
+    @classmethod
+    def avoid_collisions_with(cls, scie_name):
+        # type: (str) -> Filenames
+        return cls(
+            pex=Filename("_pex" if scie_name == "pex" else "pex"),
+            configure_binding=Filename(
+                "_configure-binding.py"
+                if scie_name == "configure-binding.py"
+                else "configure-binding.py"
+            ),
+        )
+
+    pex = attr.ib()  # type: Filename
+    configure_binding = attr.ib()  # type: Filename
+
+
 def create_manifests(
     configuration,  # type: ScieConfiguration
     name,  # type: str
     pex_info,  # type: PexInfo
     layout,  # type: Layout.Value
+    filenames,  # type: Filenames
 ):
     # type: (...) -> Iterator[Manifest]
 
@@ -84,7 +113,7 @@ def create_manifests(
         # interpreter executing the venv PEX.
         installed_pex_dir = ""
     elif layout is Layout.LOOSE:
-        installed_pex_dir = "{pex}"
+        installed_pex_dir = filenames.pex.placeholder
     else:
         production_assert(pex_info.pex_hash is not None)
         pex_hash = cast(str, pex_info.pex_hash)
@@ -102,7 +131,7 @@ def create_manifests(
             "argv1": "{scie.env.PEX_BOOTSTRAP_URLS={scie.lift}}",
         },
         "scie_jump": {"version": SCIE_JUMP_VERSION},
-        "files": [{"name": "configure-binding.py"}, {"name": "pex"}],
+        "files": [{"name": filenames.configure_binding.name}, {"name": filenames.pex.name}],
         "commands": [
             {
                 "env": {"default": env_default},
@@ -126,7 +155,7 @@ def create_manifests(
                 },
                 "name": "configure",
                 "exe": "#{cpython:python}",
-                "args": ["{pex}", "{configure-binding.py}"],
+                "args": [filenames.pex.placeholder, filenames.configure_binding.placeholder],
             }
         ],
     }  # type: Dict[str, Any]
@@ -290,9 +319,10 @@ def build(
     pex_info = PexInfo.from_pex(pex_file)
     layout = Layout.identify(pex_file)
     use_platform_suffix = len(configuration.targets) > 1
+    filenames = Filenames.avoid_collisions_with(name)
 
     errors = OrderedDict()  # type: OrderedDict[Manifest, str]
-    for manifest in create_manifests(configuration, name, pex_info, layout):
+    for manifest in create_manifests(configuration, name, pex_info, layout, filenames):
         args = [science, "--cache-dir", _science_dir(env, "cache")]
         if env.PEX_VERBOSE:
             args.append("-{verbosity}".format(verbosity="v" * env.PEX_VERBOSE))
@@ -301,12 +331,13 @@ def build(
             [
                 "lift",
                 "--file",
-                "pex={pex_file}".format(pex_file=pex_file),
+                "{name}={pex_file}".format(name=filenames.pex.name, pex_file=pex_file),
                 "--file",
-                "configure-binding.py={configure_binding}".format(
+                "{name}={configure_binding}".format(
+                    name=filenames.configure_binding.name,
                     configure_binding=os.path.join(
                         os.path.dirname(__file__), "configure-binding.py"
-                    )
+                    ),
                 ),
                 "build",
                 "--dest-dir",

pex/version.py

@@ -1,4 +1,4 @@
 # Copyright 2015 Pex project contributors.
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-__version__ = "2.13.0"
+__version__ = "2.13.1"

tests/integration/scie/test_pex_scie.py

@@ -19,6 +19,7 @@
 from pex.scie import SciePlatform, ScieStyle
 from pex.targets import LocalInterpreter
 from pex.typing import TYPE_CHECKING
+from pex.version import __version__
 from testing import IS_PYPY, PY_VER, make_env, run_pex_command
 
 if TYPE_CHECKING:
@@ -369,3 +370,32 @@ def make_20240415_3_10_14_url(platform):
         stderr.decode("utf-8"),
         flags=re.DOTALL | re.MULTILINE,
     ), stderr.decode("utf-8")
+
+
+@skip_if_pypy
+def test_pex_pex_scie(
+    tmpdir,  # type: Any
+    pex_project_dir,  # type: Any
+):
+    # type: (...) -> None
+
+    pex = os.path.join(str(tmpdir), "pex")
+    run_pex_command(
+        args=[
+            pex_project_dir,
+            "-c",
+            "pex",
+            "--scie",
+            "lazy",
+            "--scie-python-version",
+            "3.12",
+            "-o",
+            pex,
+        ]
+    ).assert_success()
+    assert (
+        __version__
+        == subprocess.check_output(args=[pex, "-V"], env=make_env(PATH=None))
+        .decode("utf-8")
+        .strip()
+    )