Merge pull request #9096 from uranusjr/new-resolver-constrainting-extraed

Constrainting an extra-ed dependency

Author: pradyunsg

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

@@ -58,6 +58,13 @@ def __and__(self, other):
         hashes = self.hashes & other.hashes(trust_internet=False)
         return Constraint(specifier, hashes)
 
+    def is_satisfied_by(self, candidate):
+        # type: (Candidate) -> bool
+        # We can safely always allow prereleases here since PackageFinder
+        # already implements the prerelease logic, and would have filtered out
+        # prerelease candidates if the user does not expect them.
+        return self.specifier.contains(candidate.version, prereleases=True)
+
 
 class Requirement(object):
     @property

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

@@ -143,6 +143,10 @@ def __init__(
         self._version = version
         self._dist = None  # type: Optional[Distribution]
 
+    def __str__(self):
+        # type: () -> str
+        return "{} {}".format(self.name, self.version)
+
     def __repr__(self):
         # type: () -> str
         return "{class_name}({link!r})".format(
@@ -359,6 +363,10 @@ def __init__(
         skip_reason = "already satisfied"
         factory.preparer.prepare_installed_requirement(self._ireq, skip_reason)
 
+    def __str__(self):
+        # type: () -> str
+        return str(self.dist)
+
     def __repr__(self):
         # type: () -> str
         return "{class_name}({distribution!r})".format(
@@ -445,6 +453,11 @@ def __init__(
         self.base = base
         self.extras = extras
 
+    def __str__(self):
+        # type: () -> str
+        name, rest = str(self.base).split(" ", 1)
+        return "{}[{}] {}".format(name, ",".join(self.extras), rest)
+
     def __repr__(self):
         # type: () -> str
         return "{class_name}(base={base!r}, extras={extras!r})".format(
@@ -554,6 +567,10 @@ def __init__(self, py_version_info):
     # only one RequiresPythonCandidate in a resolution, i.e. the host Python.
     # The built-in object.__eq__() and object.__ne__() do exactly what we want.
 
+    def __str__(self):
+        # type: () -> str
+        return "Python {}".format(self._version)
+
     @property
     def name(self):
         # type: () -> str

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

@@ -235,16 +235,10 @@ def find_candidates(
                 prefers_installed,
             )
 
-        if constraint:
-            name = explicit_candidates.pop().name
-            raise InstallationError(
-                "Could not satisfy constraints for {!r}: installation from "
-                "path or url cannot be constrained to a version".format(name)
-            )
-
         return (
             c for c in explicit_candidates
-            if all(req.is_satisfied_by(c) for req in requirements)
+            if constraint.is_satisfied_by(c)
+            and all(req.is_satisfied_by(c) for req in requirements)
         )
 
     def make_requirement_from_install_req(self, ireq, requested_extras):

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

@@ -17,6 +17,10 @@ def __init__(self, candidate):
         # type: (Candidate) -> None
         self.candidate = candidate
 
+    def __str__(self):
+        # type: () -> str
+        return str(self.candidate)
+
     def __repr__(self):
         # type: () -> str
         return "{class_name}({candidate!r})".format(
@@ -106,6 +110,10 @@ def __init__(self, specifier, match):
         self.specifier = specifier
         self._candidate = match
 
+    def __str__(self):
+        # type: () -> str
+        return "Python {}".format(self.specifier)
+
     def __repr__(self):
         # type: () -> str
         return "{class_name}({specifier!r})".format(
@@ -120,7 +128,7 @@ def name(self):
 
     def format_for_error(self):
         # type: () -> str
-        return "Python " + str(self.specifier)
+        return str(self)
 
     def get_candidate_lookup(self):
         # type: () -> CandidateLookup

tests/functional/test_install_reqs.py

@@ -341,7 +341,11 @@ def test_constraints_only_causes_error(script, data):
     assert 'installed requiresupper' not in result.stdout
 
 
-def test_constraints_local_editable_install_causes_error(script, data):
+def test_constraints_local_editable_install_causes_error(
+    script,
+    data,
+    resolver_variant,
+):
     script.scratch_path.joinpath("constraints.txt").write_text(
         "singlemodule==0.0.0"
     )
@@ -350,7 +354,11 @@ def test_constraints_local_editable_install_causes_error(script, data):
         'install', '--no-index', '-f', data.find_links, '-c',
         script.scratch_path / 'constraints.txt', '-e',
         to_install, expect_error=True)
-    assert 'Could not satisfy constraints for' in result.stderr
+    if resolver_variant == "legacy-resolver":
+        assert 'Could not satisfy constraints' in result.stderr, str(result)
+    else:
+        # Because singlemodule only has 0.0.1 available.
+        assert 'No matching distribution found' in result.stderr, str(result)
 
 
 @pytest.mark.network
@@ -362,7 +370,11 @@ def test_constraints_local_editable_install_pep518(script, data):
         'install', '--no-index', '-f', data.find_links, '-e', to_install)
 
 
-def test_constraints_local_install_causes_error(script, data):
+def test_constraints_local_install_causes_error(
+    script,
+    data,
+    resolver_variant,
+):
     script.scratch_path.joinpath("constraints.txt").write_text(
         "singlemodule==0.0.0"
     )
@@ -371,7 +383,11 @@ def test_constraints_local_install_causes_error(script, data):
         'install', '--no-index', '-f', data.find_links, '-c',
         script.scratch_path / 'constraints.txt',
         to_install, expect_error=True)
-    assert 'Could not satisfy constraints for' in result.stderr
+    if resolver_variant == "legacy-resolver":
+        assert 'Could not satisfy constraints' in result.stderr, str(result)
+    else:
+        # Because singlemodule only has 0.0.1 available.
+        assert 'No matching distribution found' in result.stderr, str(result)
 
 
 def test_constraints_constrain_to_local_editable(

tests/functional/test_new_resolver.py

@@ -712,22 +712,40 @@ def test_new_resolver_constraint_on_dependency(script):
     assert_installed(script, dep="2.0")
 
 
-def test_new_resolver_constraint_on_path(script):
+@pytest.mark.parametrize(
+    "constraint_version, expect_error, message",
+    [
+        ("1.0", True, "ERROR: No matching distribution found for foo 2.0"),
+        ("2.0", False, "Successfully installed foo-2.0"),
+    ],
+)
+def test_new_resolver_constraint_on_path_empty(
+    script,
+    constraint_version,
+    expect_error,
+    message,
+):
+    """A path requirement can be filtered by a constraint.
+    """
     setup_py = script.scratch_path / "setup.py"
     text = "from setuptools import setup\nsetup(name='foo', version='2.0')"
     setup_py.write_text(text)
+
     constraints_txt = script.scratch_path / "constraints.txt"
-    constraints_txt.write_text("foo==1.0")
+    constraints_txt.write_text("foo=={}".format(constraint_version))
+
     result = script.pip(
         "install",
         "--no-cache-dir", "--no-index",
         "-c", constraints_txt,
         str(script.scratch_path),
-        expect_error=True,
+        expect_error=expect_error,
     )
 
-    msg = "installation from path or url cannot be constrained to a version"
-    assert msg in result.stderr, str(result)
+    if expect_error:
+        assert message in result.stderr, str(result)
+    else:
+        assert message in result.stdout, str(result)
 
 
 def test_new_resolver_constraint_only_marker_match(script):
@@ -1132,3 +1150,46 @@ def test_new_resolver_check_wheel_version_normalized(
         "simple"
     )
     assert_installed(script, simple="0.1.0+local.1")
+
+
+def test_new_resolver_contraint_on_dep_with_extra(script):
+    create_basic_wheel_for_package(
+        script,
+        name="simple",
+        version="1",
+        depends=["dep[x]"],
+    )
+    create_basic_wheel_for_package(
+        script,
+        name="dep",
+        version="1",
+        extras={"x": ["depx==1"]},
+    )
+    create_basic_wheel_for_package(
+        script,
+        name="dep",
+        version="2",
+        extras={"x": ["depx==2"]},
+    )
+    create_basic_wheel_for_package(
+        script,
+        name="depx",
+        version="1",
+    )
+    create_basic_wheel_for_package(
+        script,
+        name="depx",
+        version="2",
+    )
+
+    constraints_txt = script.scratch_path / "constraints.txt"
+    constraints_txt.write_text("dep==1")
+
+    script.pip(
+        "install",
+        "--no-cache-dir", "--no-index",
+        "--find-links", script.scratch_path,
+        "--constraint", constraints_txt,
+        "simple",
+    )
+    assert_installed(script, simple="1", dep="1", depx="1")