Adds excludes field to jvm_artifact targets

src/python/pants/jvm/resolve/common.py

@@ -3,6 +3,7 @@
 
 from __future__ import annotations
 
+import dataclasses
 import re
 from dataclasses import dataclass
 from typing import Iterable
@@ -12,6 +13,7 @@
 from pants.engine.target import Target
 from pants.jvm.target_types import (
     JvmArtifactArtifactField,
+    JvmArtifactExcludeDependenciesField,
     JvmArtifactFieldSet,
     JvmArtifactGroupField,
     JvmArtifactJarSourceField,
@@ -149,6 +151,7 @@ class ArtifactRequirement:
 
     url: str | None = None
     jar: JvmArtifactJarSourceField | None = None
+    excludes: frozenset[str] | None = None
 
     @classmethod
     def from_jvm_artifact_target(cls, target: Target) -> ArtifactRequirement:
@@ -157,6 +160,7 @@ def from_jvm_artifact_target(cls, target: Target) -> ArtifactRequirement:
                 "`ArtifactRequirement.from_jvm_artifact_target()` only works on targets with "
                 "`JvmArtifactFieldSet` fields present."
             )
+
         return ArtifactRequirement(
             coordinate=Coordinate(
                 group=target[JvmArtifactGroupField].value,
@@ -169,6 +173,17 @@ def from_jvm_artifact_target(cls, target: Target) -> ArtifactRequirement:
                 if target[JvmArtifactJarSourceField].value
                 else None
             ),
+            excludes=frozenset(target[JvmArtifactExcludeDependenciesField].value or []) or None,
+        )
+
+    def exclude(self, *excludes: str) -> ArtifactRequirement:
+        """Creates a copy of this `ArtifactRequirement` with `excludes` provided.
+
+        Mostly useful for testing (`Coordinate(...).as_requirement().exclude(...)`).
+        """
+
+        return dataclasses.replace(
+            self, excludes=self.excludes.union(excludes) if self.excludes else frozenset(excludes)
         )
 
     def to_coord_arg_str(self) -> str:
@@ -177,12 +192,14 @@ def to_coord_arg_str(self) -> str:
         )
 
     def to_metadata_str(self) -> str:
-        return self.coordinate.to_coord_arg_str(
-            {
-                "url": self.url or "not_provided",
-                "jar": self.jar.address.spec if self.jar else "not_provided",
-            }
-        )
+        attrs = {
+            "url": self.url or "not_provided",
+            "jar": self.jar.address.spec if self.jar else "not_provided",
+        }
+        if self.excludes:
+            attrs["excludes"] = ",".join(self.excludes)
+
+        return self.coordinate.to_coord_arg_str(attrs)
 
 
 # TODO: Consider whether to carry classpath scope in some fashion via ArtifactRequirements.
@@ -197,7 +214,7 @@ def from_coordinates(cls, coordinates: Iterable[Coordinate]) -> ArtifactRequirem
 @dataclass(frozen=True)
 class GatherJvmCoordinatesRequest:
     """A request to turn strings of coordinates (`group:artifact:version`) and/or addresses to
-    `jar_artifact` targets into `ArtifactRequirements`."""
+    `jvm_artifact` targets into `ArtifactRequirements`."""
 
     artifact_inputs: FrozenOrderedSet[str]
     option_name: str

src/python/pants/jvm/resolve/coursier_fetch.py

@@ -5,6 +5,7 @@
 
 import dataclasses
 import importlib.resources
+import itertools
 import json
 import logging
 import os
@@ -22,15 +23,18 @@
 from pants.engine.collection import Collection
 from pants.engine.fs import (
     AddPrefix,
+    CreateDigest,
     Digest,
     DigestContents,
     DigestSubset,
+    FileContent,
     FileDigest,
     MergeDigests,
     PathGlobs,
     RemovePrefix,
     Snapshot,
 )
+from pants.engine.internals.native_engine import EMPTY_DIGEST
 from pants.engine.process import ProcessResult
 from pants.engine.rules import Get, MultiGet, collect_rules, rule
 from pants.engine.target import CoarsenedTargets, Target, Targets
@@ -289,8 +293,17 @@ def classpath_dest_filename(coord: str, src_filename: str) -> str:
 @dataclass(frozen=True)
 class CoursierResolveInfo:
     coord_arg_strings: FrozenSet[str]
+    extra_args: tuple[str, ...]
     digest: Digest
 
+    @property
+    def argv(self) -> Iterable[str]:
+        """Return coursier arguments that can be used to compute or fetch this resolve.
+
+        Must be used in concert with `digest`.
+        """
+        return itertools.chain(self.coord_arg_strings, self.extra_args)
+
 
 @rule
 async def prepare_coursier_resolve_info(
@@ -300,6 +313,9 @@ async def prepare_coursier_resolve_info(
     # URLs, and put the files in the place specified by the URLs.
     no_jars: List[ArtifactRequirement] = []
     jars: List[Tuple[ArtifactRequirement, JvmArtifactJarSourceField]] = []
+    extra_args: List[str] = []
+
+    LOCAL_EXCLUDE_FILE = "PANTS_RESOLVE_EXCLUDES"
 
     for req in artifact_requirements:
         jar = req.jar
@@ -308,6 +324,23 @@ async def prepare_coursier_resolve_info(
         else:
             jars.append((req, jar))
 
+    excludes = [
+        (req.coordinate, exclude)
+        for req in artifact_requirements
+        for exclude in (req.excludes or [])
+    ]
+
+    excludes_digest = EMPTY_DIGEST
+    if excludes:
+        excludes_file_content = FileContent(
+            LOCAL_EXCLUDE_FILE,
+            "\n".join(
+                f"{coord.group}:{coord.artifact}--{exclude}" for (coord, exclude) in excludes
+            ).encode("utf-8"),
+        )
+        excludes_digest = await Get(Digest, CreateDigest([excludes_file_content]))
+        extra_args += ["--local-exclude-file", LOCAL_EXCLUDE_FILE]
+
     jar_files = await Get(SourceFiles, SourceFilesRequest(i[1] for i in jars))
     jar_file_paths = jar_files.snapshot.files
 
@@ -320,9 +353,12 @@ async def prepare_coursier_resolve_info(
 
     to_resolve = chain(no_jars, resolvable_jar_requirements)
 
+    digest = await Get(Digest, MergeDigests([jar_files.snapshot.digest, excludes_digest]))
+
     return CoursierResolveInfo(
         coord_arg_strings=frozenset(req.to_coord_arg_str() for req in to_resolve),
-        digest=jar_files.snapshot.digest,
+        digest=digest,
+        extra_args=tuple(extra_args),
     )
 
 
@@ -368,7 +404,7 @@ async def coursier_resolve_lockfile(
         CoursierFetchProcess(
             args=(
                 coursier_report_file_name,
-                *coursier_resolve_info.coord_arg_strings,
+                *coursier_resolve_info.argv,
             ),
             input_digest=coursier_resolve_info.digest,
             output_directories=("classpath",),
@@ -523,7 +559,7 @@ async def coursier_fetch_one_coord(
             args=(
                 coursier_report_file_name,
                 "--intransitive",
-                *coursier_resolve_info.coord_arg_strings,
+                *coursier_resolve_info.argv,
             ),
             input_digest=coursier_resolve_info.digest,
             output_directories=("classpath",),

src/python/pants/jvm/resolve/coursier_fetch_integration_test.py

@@ -606,3 +606,30 @@ def test_user_repo_order_is_respected(rule_runner: RuleRunner) -> None:
             ArtifactRequirements.from_coordinates([jai_core]),
         ],
     )
+
+
+@maybe_skip_jdk_test
+def test_transitive_excludes(rule_runner: RuleRunner) -> None:
+    resolve = rule_runner.request(
+        CoursierResolvedLockfile,
+        [
+            ArtifactRequirements(
+                [
+                    Coordinate(
+                        group="com.fasterxml.jackson.core",
+                        artifact="jackson-databind",
+                        version="2.12.1",
+                    )
+                    .as_requirement()
+                    .exclude("com.fasterxml.jackson.core:jackson-core")
+                ]
+            ),
+        ],
+    )
+
+    entries = resolve.entries
+    jackson_databind = [i for i in entries if i.coord.artifact == "jackson-databind"][0]
+    jackson_cores = [i for i in entries if i.coord.artifact == "jackson-core"]
+
+    assert jackson_databind.coord.version == "2.12.1"
+    assert len(jackson_cores) == 0

src/python/pants/jvm/target_types.py

@@ -168,6 +168,19 @@ class JvmProvidesTypesField(StringSequenceField):
     )
 
 
+class JvmArtifactExcludeDependenciesField(StringSequenceField):
+    alias = "exclude_dependencies"
+    help = (
+        "A list of unversioned coordinates (i.e. `group:artifact`) that should be excluded "
+        "as dependencies when this artifact is resolved.\n\n"
+        "This does not prevent this artifact from being included in the resolve as a dependency "
+        "of other artifacts that depend on it, and is currently intended as a way to resolve "
+        "version conflicts in complex resolves.\n\n"
+        "These values are passed directly to Coursier, and if specified incorrectly will show a "
+        "parse error from Coursier."
+    )
+
+
 class JvmArtifactResolveField(JvmResolveField):
     help = (
         "The resolve from `[jvm].resolves` that this artifact should be included in.\n\n"
@@ -204,6 +217,7 @@ class JvmArtifactTarget(Target):
         JvmArtifactUrlField,  # TODO: should `JvmArtifactFieldSet` have an `all_fields` field?
         JvmArtifactJarSourceField,
         JvmArtifactResolveField,
+        JvmArtifactExcludeDependenciesField,
     )
     help = (
         "A third-party JVM artifact, as identified by its Maven-compatible coordinate.\n\n"