Fix setup_py().with_binaries() to use the default entry point

src/python/pants/backend/python/goals/package_pex_binary.py

@@ -1,7 +1,6 @@
 # Copyright 2019 Pants project contributors (see CONTRIBUTORS.md).
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-import os
 from dataclasses import dataclass
 from typing import Tuple, cast
 
@@ -15,7 +14,12 @@
     PexInheritPathField,
 )
 from pants.backend.python.target_types import PexPlatformsField as PythonPlatformsField
-from pants.backend.python.target_types import PexShebangField, PexZipSafeField
+from pants.backend.python.target_types import (
+    PexShebangField,
+    PexZipSafeField,
+    ResolvedPexEntryPoint,
+    ResolvePexEntryPointRequest,
+)
 from pants.backend.python.util_rules.pex import PexPlatforms, TwoStepPex
 from pants.backend.python.util_rules.pex_from_targets import (
     PexFromTargetsRequest,
@@ -29,12 +33,9 @@
     PackageFieldSet,
 )
 from pants.core.goals.run import RunFieldSet
-from pants.engine.fs import PathGlobs, Paths
 from pants.engine.rules import Get, collect_rules, rule
-from pants.engine.target import InvalidFieldException
 from pants.engine.unions import UnionRule
-from pants.option.global_options import FilesNotFoundBehavior, GlobalOptions
-from pants.source.source_root import SourceRoot, SourceRootRequest
+from pants.option.global_options import GlobalOptions
 from pants.util.logging import LogLevel
 
 
@@ -77,27 +78,9 @@ async def package_pex_binary(
     pex_binary_defaults: PexBinaryDefaults,
     global_options: GlobalOptions,
 ) -> BuiltPackage:
-    entry_point = field_set.entry_point.value
-    if entry_point is None:
-        binary_source_paths = await Get(
-            Paths, PathGlobs, field_set.sources.path_globs(FilesNotFoundBehavior.error)
-        )
-        if len(binary_source_paths.files) != 1:
-            raise InvalidFieldException(
-                "No `entry_point` was set for the target "
-                f"{repr(field_set.address)}, so it must have exactly one source, but it has "
-                f"{len(binary_source_paths.files)}"
-            )
-        entry_point_path = binary_source_paths.files[0]
-        source_root = await Get(
-            SourceRoot,
-            SourceRootRequest,
-            SourceRootRequest.for_file(entry_point_path),
-        )
-        entry_point = PexBinarySources.translate_source_file_to_entry_point(
-            os.path.relpath(entry_point_path, source_root.path)
-        )
-
+    resolved_entry_point = await Get(
+        ResolvedPexEntryPoint, ResolvePexEntryPointRequest(field_set.entry_point, field_set.sources)
+    )
     output_filename = field_set.output_path.value_or_default(
         field_set.address,
         file_ending="pex",
@@ -109,7 +92,7 @@ async def package_pex_binary(
             PexFromTargetsRequest(
                 addresses=[field_set.address],
                 internal_only=False,
-                entry_point=entry_point,
+                entry_point=resolved_entry_point.val,
                 platforms=PexPlatforms.create_from_platforms_field(field_set.platforms),
                 output_filename=output_filename,
                 additional_args=field_set.generate_additional_args(pex_binary_defaults),

src/python/pants/backend/python/goals/pytest_runner_integration_test.py

@@ -18,6 +18,7 @@
     PythonLibrary,
     PythonRequirementLibrary,
     PythonTests,
+    resolve_pex_entry_point,
 )
 from pants.backend.python.util_rules import pex_from_targets
 from pants.core.goals import binary
@@ -42,6 +43,7 @@ def rule_runner() -> RuleRunner:
             *binary.rules(),
             *package_pex_binary.rules(),
             get_filtered_environment,
+            resolve_pex_entry_point,
             QueryRule(TestResult, (PythonTestFieldSet,)),
             QueryRule(TestDebugRequest, (PythonTestFieldSet,)),
         ],

src/python/pants/backend/python/goals/run_pex_binary.py

@@ -4,7 +4,11 @@
 import os
 
 from pants.backend.python.goals.package_pex_binary import PexBinaryFieldSet
-from pants.backend.python.target_types import PexBinaryDefaults, PexBinarySources
+from pants.backend.python.target_types import (
+    PexBinaryDefaults,
+    ResolvedPexEntryPoint,
+    ResolvePexEntryPointRequest,
+)
 from pants.backend.python.util_rules.pex import Pex, PexRequest
 from pants.backend.python.util_rules.pex_environment import PexEnvironment
 from pants.backend.python.util_rules.pex_from_targets import PexFromTargetsRequest
@@ -13,12 +17,10 @@
     PythonSourceFilesRequest,
 )
 from pants.core.goals.run import RunFieldSet, RunRequest
-from pants.engine.fs import Digest, MergeDigests, PathGlobs, Paths
+from pants.engine.fs import Digest, MergeDigests
 from pants.engine.rules import Get, MultiGet, collect_rules, rule
-from pants.engine.target import InvalidFieldException, TransitiveTargets, TransitiveTargetsRequest
+from pants.engine.target import TransitiveTargets, TransitiveTargetsRequest
 from pants.engine.unions import UnionRule
-from pants.option.global_options import FilesNotFoundBehavior
-from pants.source.source_root import SourceRoot, SourceRootRequest
 from pants.util.logging import LogLevel
 
 
@@ -28,26 +30,13 @@ async def create_pex_binary_run_request(
     pex_binary_defaults: PexBinaryDefaults,
     pex_env: PexEnvironment,
 ) -> RunRequest:
-    entry_point = field_set.entry_point.value
-    if entry_point is None:
-        binary_source_paths = await Get(
-            Paths, PathGlobs, field_set.sources.path_globs(FilesNotFoundBehavior.error)
-        )
-        if len(binary_source_paths.files) != 1:
-            raise InvalidFieldException(
-                "No `entry_point` was set for the target "
-                f"{repr(field_set.address)}, so it must have exactly one source, but it has "
-                f"{len(binary_source_paths.files)}"
-            )
-        entry_point_path = binary_source_paths.files[0]
-        source_root = await Get(
-            SourceRoot,
-            SourceRootRequest,
-            SourceRootRequest.for_file(entry_point_path),
-        )
-        entry_point = PexBinarySources.translate_source_file_to_entry_point(
-            os.path.relpath(entry_point_path, source_root.path)
-        )
+    entry_point, transitive_targets = await MultiGet(
+        Get(
+            ResolvedPexEntryPoint,
+            ResolvePexEntryPointRequest(field_set.entry_point, field_set.sources),
+        ),
+        Get(TransitiveTargets, TransitiveTargetsRequest([field_set.address])),
+    )
     transitive_targets = await Get(TransitiveTargets, TransitiveTargetsRequest([field_set.address]))
 
     # Note that we get an intermediate PexRequest here (instead of going straight to a Pex)
@@ -72,9 +61,9 @@ async def create_pex_binary_run_request(
             interpreter_constraints=requirements_pex_request.interpreter_constraints,
             additional_args=field_set.generate_additional_args(pex_binary_defaults),
             internal_only=True,
-            # Note that the entry point file is not in the Pex itself, but on the
-            # PEX_PATH. This works fine!
-            entry_point=entry_point,
+            # Note that the entry point file is not in the PEX itself. It's loaded by setting
+            # `PEX_EXTRA_SYS_PATH`.
+            entry_point=entry_point.val,
         ),
     )
 

src/python/pants/backend/python/goals/setup_py.py

@@ -15,11 +15,14 @@
 from pants.backend.python.macros.python_artifact import PythonArtifact
 from pants.backend.python.subsystems.setuptools import Setuptools
 from pants.backend.python.target_types import (
+    PexBinarySources,
     PexEntryPointField,
     PythonInterpreterCompatibility,
     PythonProvidesField,
     PythonRequirementsField,
     PythonSources,
+    ResolvedPexEntryPoint,
+    ResolvePexEntryPointRequest,
     SetupPyCommandsField,
 )
 from pants.backend.python.util_rules.pex import (
@@ -682,19 +685,31 @@ async def generate_chroot(request: SetupPyChrootRequest) -> SetupPyChroot:
             "install_requires": (*requirements, *setup_kwargs.get("install_requires", [])),
         }
     )
+
+    # Add any `pex_binary` targets from `setup_py().with_binaries()` to the dist's entry points.
     key_to_binary_spec = exported_target.provides.binaries
     binaries = await Get(
         Targets, UnparsedAddressInputs(key_to_binary_spec.values(), owning_address=target.address)
     )
-    for key, binary in zip(key_to_binary_spec.keys(), binaries):
-        binary_entry_point = binary.get(PexEntryPointField).value
-        if not binary_entry_point:
+    entry_point_requests = []
+    for binary in binaries:
+        if not binary.has_fields([PexEntryPointField, PexBinarySources]):
             raise InvalidEntryPoint(
-                f"The binary {key} exported by {target.address} is not a valid entry point."
+                "Expected addresses to `pex_binary` targets in `.with_binaries()` for the "
+                f"`provides` field for {exported_target.target.address}, "
+                f"but found {binary.address} with target type {binary.alias}."
             )
+        entry_point_requests.append(
+            ResolvePexEntryPointRequest(binary[PexEntryPointField], binary[PexBinarySources])
+        )
+    binary_entry_points = await MultiGet(
+        Get(ResolvedPexEntryPoint, ResolvePexEntryPointRequest, request)
+        for request in entry_point_requests
+    )
+    for key, binary_entry_point in zip(key_to_binary_spec.keys(), binary_entry_points):
         entry_points = setup_kwargs["entry_points"] = setup_kwargs.get("entry_points", {})
         console_scripts = entry_points["console_scripts"] = entry_points.get("console_scripts", [])
-        console_scripts.append(f"{key}={binary_entry_point}")
+        console_scripts.append(f"{key}={binary_entry_point.val}")
 
     # Generate the setup script.
     setup_py_content = SETUP_BOILERPLATE.format(

src/python/pants/backend/python/goals/setup_py_test.py

@@ -40,14 +40,15 @@
     PythonDistribution,
     PythonLibrary,
     PythonRequirementLibrary,
+    resolve_pex_entry_point,
 )
 from pants.backend.python.util_rules import python_sources
 from pants.core.target_types import Files, Resources
 from pants.engine.addresses import Address
 from pants.engine.fs import Snapshot
 from pants.engine.internals.scheduler import ExecutionError
 from pants.engine.rules import SubsystemRule, rule
-from pants.engine.target import Targets
+from pants.engine.target import InvalidFieldException, Targets
 from pants.engine.unions import UnionRule
 from pants.testutil.rule_runner import QueryRule, RuleRunner
 
@@ -95,6 +96,7 @@ def chroot_rule_runner() -> RuleRunner:
             get_exporting_owner,
             *python_sources.rules(),
             setup_kwargs_plugin,
+            resolve_pex_entry_point,
             SubsystemRule(SetupPyGeneration),
             UnionRule(SetupKwargsRequest, PluginSetupKwargsRequest),
             QueryRule(SetupPyChroot, (SetupPyChrootRequest,)),
@@ -254,7 +256,7 @@ def test_invalid_binary(chroot_rule_runner: RuleRunner) -> None:
     assert_chroot_error(
         chroot_rule_runner,
         Address("src/python/invalid_binary", target_name="invalid_bin2"),
-        InvalidEntryPoint,
+        InvalidFieldException,
     )
 
 

src/python/pants/backend/python/target_types.py

@@ -4,6 +4,7 @@
 import collections.abc
 import logging
 import os.path
+from dataclasses import dataclass
 from textwrap import dedent
 from typing import Iterable, Optional, Tuple, Union, cast
 
@@ -14,6 +15,7 @@
 from pants.base.deprecated import resolve_conflicting_options, warn_or_error
 from pants.core.goals.package import OutputPathField
 from pants.engine.addresses import Address, Addresses, UnparsedAddressInputs
+from pants.engine.fs import PathGlobs, Paths
 from pants.engine.rules import Get, collect_rules, rule
 from pants.engine.target import (
     COMMON_TARGET_FIELDS,
@@ -36,9 +38,11 @@
     Target,
     WrappedTarget,
 )
+from pants.option.global_options import FilesNotFoundBehavior
 from pants.option.subsystem import Subsystem
 from pants.python.python_requirement import PythonRequirement
 from pants.python.python_setup import PythonSetup
+from pants.source.source_root import SourceRoot, SourceRootRequest
 
 logger = logging.getLogger(__name__)
 
@@ -141,18 +145,13 @@ class PexBinarySources(PythonSources):
 
     expected_num_files = range(0, 2)
 
-    @staticmethod
-    def translate_source_file_to_entry_point(stripped_source_path: str) -> str:
-        module_base, _ = os.path.splitext(stripped_source_path)
-        return module_base.replace(os.path.sep, ".")
-
 
 class PexBinaryDependencies(Dependencies):
     supports_transitive_excludes = True
 
 
 class PexEntryPointField(StringField):
-    """The default entry point for the binary.
+    """The entry point for the binary.
 
     If omitted, Pants will use the module name from the `sources` field, e.g. `project/app.py` will
     become the entry point `project.app` .
@@ -161,6 +160,44 @@ class PexEntryPointField(StringField):
     alias = "entry_point"
 
 
+@dataclass(frozen=True)
+class ResolvedPexEntryPoint:
+    val: str
+
+
+@dataclass(frozen=True)
+class ResolvePexEntryPointRequest:
+    """Determine the entry_point by using the `PexEntryPointField` and falling back to the sources
+    field."""
+
+    entry_point_field: PexEntryPointField
+    sources: PexBinarySources
+
+
+@rule
+async def resolve_pex_entry_point(request: ResolvePexEntryPointRequest) -> ResolvedPexEntryPoint:
+    if request.entry_point_field.value:
+        return ResolvedPexEntryPoint(request.entry_point_field.value)
+    binary_source_paths = await Get(
+        Paths, PathGlobs, request.sources.path_globs(FilesNotFoundBehavior.error)
+    )
+    if len(binary_source_paths.files) != 1:
+        raise InvalidFieldException(
+            "No `entry_point` was set for the target "
+            f"{repr(request.sources.address)}, so it must have exactly one source, but it has "
+            f"{len(binary_source_paths.files)}."
+        )
+    entry_point_path = binary_source_paths.files[0]
+    source_root = await Get(
+        SourceRoot,
+        SourceRootRequest,
+        SourceRootRequest.for_file(entry_point_path),
+    )
+    stripped_source_path = os.path.relpath(entry_point_path, source_root.path)
+    module_base, _ = os.path.splitext(stripped_source_path)
+    return ResolvedPexEntryPoint(module_base.replace(os.path.sep, "."))
+
+
 class PexPlatformsField(StringOrStringSequenceField):
     """The platforms the built PEX should be compatible with.