Add per-requirement --no-deps option support in requirements.txt

news/9948.feature.rst

@@ -0,0 +1 @@
+Add a per-requirement ``--no-deps`` option.

src/pip/_internal/cli/req_command.py

@@ -345,6 +345,7 @@ def make_resolver(
         """
         make_install_req = partial(
             install_req_from_req_string,
+            ignore_dependencies=options.ignore_dependencies,
             isolated=options.isolated_mode,
             use_pep517=use_pep517,
         )

src/pip/_internal/operations/check.py

@@ -100,7 +100,9 @@ def check_install_conflicts(to_install: List[InstallRequirement]) -> ConflictDet
     # Start from the current state
     package_set, _ = create_package_set_from_installed()
     # Install packages
-    would_be_installed = _simulate_installation_of(to_install, package_set)
+    would_be_installed = _simulate_installation_of(
+        list(filter(lambda x: not x.ignore_dependencies, to_install)), package_set
+    )
 
     # Only warn about directly-dependent packages; create a whitelist of them
     whitelist = _create_whitelist(would_be_installed, package_set)

src/pip/_internal/req/constructors.py

@@ -224,6 +224,9 @@ def install_req_from_editable(
         install_options=options.get("install_options", []) if options else [],
         global_options=options.get("global_options", []) if options else [],
         hash_options=options.get("hashes", {}) if options else {},
+        ignore_dependencies=options.get("ignore_dependencies", False)
+        if options
+        else False,
         extras=parts.extras,
     )
 
@@ -399,6 +402,9 @@ def install_req_from_line(
         install_options=options.get("install_options", []) if options else [],
         global_options=options.get("global_options", []) if options else [],
         hash_options=options.get("hashes", {}) if options else {},
+        ignore_dependencies=options.get("ignore_dependencies", False)
+        if options
+        else False,
         constraint=constraint,
         extras=parts.extras,
         user_supplied=user_supplied,
@@ -409,6 +415,7 @@ def install_req_from_req_string(
     req_string: str,
     comes_from: Optional[InstallRequirement] = None,
     isolated: bool = False,
+    ignore_dependencies: bool = False,
     use_pep517: Optional[bool] = None,
     user_supplied: bool = False,
 ) -> InstallRequirement:
@@ -438,6 +445,7 @@ def install_req_from_req_string(
         req,
         comes_from,
         isolated=isolated,
+        ignore_dependencies=ignore_dependencies,
         use_pep517=use_pep517,
         user_supplied=user_supplied,
     )
@@ -456,6 +464,7 @@ def install_req_from_parsed_requirement(
             use_pep517=use_pep517,
             constraint=parsed_req.constraint,
             isolated=isolated,
+            options=parsed_req.options,
             user_supplied=user_supplied,
         )
 
@@ -486,5 +495,6 @@ def install_req_from_link_and_ireq(
         isolated=ireq.isolated,
         install_options=ireq.install_options,
         global_options=ireq.global_options,
+        ignore_dependencies=ireq.ignore_dependencies,
         hash_options=ireq.hash_options,
     )

src/pip/_internal/req/req_file.py

@@ -72,6 +72,7 @@
     cmdoptions.install_options,
     cmdoptions.global_options,
     cmdoptions.hash,
+    cmdoptions.no_deps,
 ]
 
 # the 'dest' string values

src/pip/_internal/req/req_install.py

@@ -80,6 +80,7 @@ def __init__(
         install_options: Optional[List[str]] = None,
         global_options: Optional[List[str]] = None,
         hash_options: Optional[Dict[str, List[str]]] = None,
+        ignore_dependencies: bool = False,
         constraint: bool = False,
         extras: Collection[str] = (),
         user_supplied: bool = False,
@@ -138,6 +139,7 @@ def __init__(
         self.install_options = install_options if install_options else []
         self.global_options = global_options if global_options else []
         self.hash_options = hash_options if hash_options else {}
+        self.ignore_dependencies = ignore_dependencies
         # Set to True after successful preparation of this requirement
         self.prepared = False
         # User supplied requirement are explicitly requested for installation
@@ -252,6 +254,13 @@ def match_markers(self, extras_requested: Optional[Iterable[str]] = None) -> boo
         else:
             return True
 
+    @property
+    def has_ignore_dependencies(self) -> bool:
+        if isinstance(self.comes_from, InstallRequirement):
+            return self.comes_from.ignore_dependencies
+        else:
+            return self.ignore_dependencies
+
     @property
     def has_hash_options(self) -> bool:
         """Return whether any known-good hashes are specified as options.

src/pip/_internal/resolution/resolvelib/candidates.py

@@ -37,6 +37,16 @@
 REQUIRES_PYTHON_IDENTIFIER = cast(NormalizedName, "<Python from Requires-Python>")
 
 
+def has_ignore_dependencies(candidate: Candidate) -> bool:
+    ireq = candidate.get_install_requirement()
+    if ireq:
+        return ireq.has_ignore_dependencies
+    elif isinstance(candidate, AlreadyInstalledCandidate):
+        return candidate._ireq.has_ignore_dependencies
+    else:
+        return False
+
+
 def as_base_candidate(candidate: Candidate) -> Optional[BaseCandidate]:
     """The runtime version of BaseCandidate."""
     base_candidate_classes = (
@@ -68,6 +78,7 @@ def make_install_req_from_link(
             install_options=template.install_options,
             global_options=template.global_options,
             hashes=template.hash_options,
+            ignore_dependencies=template.ignore_dependencies,
         ),
     )
     ireq.original_link = template.original_link
@@ -91,6 +102,7 @@ def make_install_req_from_editable(
             install_options=template.install_options,
             global_options=template.global_options,
             hashes=template.hash_options,
+            ignore_dependencies=template.ignore_dependencies,
         ),
     )
 
@@ -115,6 +127,7 @@ def _make_install_req_from_dist(
             install_options=template.install_options,
             global_options=template.global_options,
             hashes=template.hash_options,
+            ignore_dependencies=template.ignore_dependencies,
         ),
     )
     ireq.satisfied_by = dist

src/pip/_internal/resolution/resolvelib/provider.py

@@ -14,7 +14,7 @@
 from pip._vendor.resolvelib.providers import AbstractProvider
 
 from .base import Candidate, Constraint, Requirement
-from .candidates import REQUIRES_PYTHON_IDENTIFIER
+from .candidates import REQUIRES_PYTHON_IDENTIFIER, has_ignore_dependencies
 from .factory import Factory
 
 if TYPE_CHECKING:
@@ -233,7 +233,9 @@ def is_satisfied_by(self, requirement: Requirement, candidate: Candidate) -> boo
         return requirement.is_satisfied_by(candidate)
 
     def get_dependencies(self, candidate: Candidate) -> Sequence[Requirement]:
-        with_requires = not self._ignore_dependencies
+        with_requires = not (
+            self._ignore_dependencies or has_ignore_dependencies(candidate)
+        )
         return [r for r in candidate.iter_dependencies(with_requires) if r is not None]
 
     @staticmethod

tests/functional/test_install_reqs.py

@@ -816,3 +816,23 @@ def test_location_related_install_option_fails(script: PipTestEnvironment) -> No
         expect_error=True,
     )
     assert "['--home'] from simple" in result.stderr
+
+
+def test_install_options_no_deps(script: PipTestEnvironment) -> None:
+    create_basic_wheel_for_package(script, "A", "0.1.0", depends=["B==0.1.0"])
+    create_basic_wheel_for_package(script, "B", "0.1.0")
+
+    requirements_txt = script.scratch_path / "requirements.txt"
+    requirements_txt.write_text("A --no-deps")
+
+    script.pip(
+        "install",
+        "--no-cache-dir",
+        "--find-links",
+        script.scratch_path,
+        "-r",
+        requirements_txt,
+        "--only-binary=:all:",
+    )
+    script.assert_installed(A="0.1.0")
+    script.assert_not_installed("B")