clearer error handling (#514)

- raise and catch more precise errors
- version-parsing errors on a package are caught and re-raised with text saying what the package is

src/poetry/core/constraints/generic/parser.py

@@ -7,6 +7,7 @@
 from poetry.core.constraints.generic.any_constraint import AnyConstraint
 from poetry.core.constraints.generic.constraint import Constraint
 from poetry.core.constraints.generic.union_constraint import UnionConstraint
+from poetry.core.constraints.version.exceptions import ParseConstraintError
 
 
 if TYPE_CHECKING:
@@ -61,4 +62,4 @@ def parse_single_constraint(constraint: str) -> Constraint:
 
         return Constraint(version, op)
 
-    raise ValueError(f"Could not parse version constraint: {constraint}")
+    raise ParseConstraintError(f"Could not parse version constraint: {constraint}")

src/poetry/core/constraints/version/parser.py

@@ -4,6 +4,9 @@
 
 from typing import TYPE_CHECKING
 
+from poetry.core.constraints.version.exceptions import ParseConstraintError
+from poetry.core.version.exceptions import InvalidVersion
+
 
 if TYPE_CHECKING:
     from poetry.core.constraints.version.version_constraint import VersionConstraint
@@ -66,7 +69,13 @@ def parse_single_constraint(constraint: str) -> VersionConstraint:
     # Tilde range
     m = TILDE_CONSTRAINT.match(constraint)
     if m:
-        version = Version.parse(m.group("version"))
+        try:
+            version = Version.parse(m.group("version"))
+        except InvalidVersion as e:
+            raise ParseConstraintError(
+                f"Could not parse version constraint: {constraint}"
+            ) from e
+
         high = version.stable.next_minor()
         if version.release.precision == 1:
             high = version.stable.next_major()
@@ -76,7 +85,13 @@ def parse_single_constraint(constraint: str) -> VersionConstraint:
     # PEP 440 Tilde range (~=)
     m = TILDE_PEP440_CONSTRAINT.match(constraint)
     if m:
-        version = Version.parse(m.group("version"))
+        try:
+            version = Version.parse(m.group("version"))
+        except InvalidVersion as e:
+            raise ParseConstraintError(
+                f"Could not parse version constraint: {constraint}"
+            ) from e
+
         if version.release.precision == 2:
             high = version.stable.next_major()
         else:
@@ -87,7 +102,12 @@ def parse_single_constraint(constraint: str) -> VersionConstraint:
     # Caret range
     m = CARET_CONSTRAINT.match(constraint)
     if m:
-        version = Version.parse(m.group("version"))
+        try:
+            version = Version.parse(m.group("version"))
+        except InvalidVersion as e:
+            raise ParseConstraintError(
+                f"Could not parse version constraint: {constraint}"
+            ) from e
 
         return VersionRange(version, version.next_breaking(), include_min=True)
 
@@ -127,8 +147,10 @@ def parse_single_constraint(constraint: str) -> VersionConstraint:
 
         try:
             version = Version.parse(version_string)
-        except ValueError:
-            raise ValueError(f"Could not parse version constraint: {constraint}")
+        except InvalidVersion as e:
+            raise ParseConstraintError(
+                f"Could not parse version constraint: {constraint}"
+            ) from e
 
         if op == "<":
             return VersionRange(max=version)
@@ -142,6 +164,4 @@ def parse_single_constraint(constraint: str) -> VersionConstraint:
             return VersionUnion(VersionRange(max=version), VersionRange(min=version))
         return version
 
-    from poetry.core.constraints.version.exceptions import ParseConstraintError
-
     raise ParseConstraintError(f"Could not parse version constraint: {constraint}")

src/poetry/core/packages/package.py

@@ -12,9 +12,11 @@
 from typing import TypeVar
 
 from poetry.core.constraints.version import parse_constraint
+from poetry.core.constraints.version.exceptions import ParseConstraintError
 from poetry.core.packages.dependency_group import MAIN_GROUP
 from poetry.core.packages.specification import PackageSpecification
 from poetry.core.packages.utils.utils import create_nested_marker
+from poetry.core.version.exceptions import InvalidVersion
 from poetry.core.version.markers import parse_marker
 
 
@@ -215,11 +217,15 @@ def _set_version(
         from poetry.core.constraints.version import Version
 
         if not isinstance(version, Version):
-            self._version = Version.parse(version)
-            self._pretty_version = pretty_version or version
-        else:
-            self._version = version
-            self._pretty_version = pretty_version or self._version.text
+            try:
+                version = Version.parse(version)
+            except InvalidVersion:
+                raise InvalidVersion(
+                    f"Invalid version '{version}' on package {self.name}"
+                )
+
+        self._version = version
+        self._pretty_version = pretty_version or version.text
 
     def _get_author(self) -> dict[str, str | None]:
         if not self._authors:
@@ -261,8 +267,13 @@ def python_versions(self) -> str:
 
     @python_versions.setter
     def python_versions(self, value: str) -> None:
+        try:
+            constraint = parse_constraint(value)
+        except ParseConstraintError:
+            raise ParseConstraintError(f"Invalid python versions '{value}' on {self}")
+
         self._python_versions = value
-        self._python_constraint = parse_constraint(value)
+        self._python_constraint = constraint
         self._python_marker = parse_marker(
             create_nested_marker("python_version", self._python_constraint)
         )

src/poetry/core/version/markers.py

@@ -199,7 +199,7 @@ def __init__(
         # Extract operator and value
         m = self._CONSTRAINT_RE.match(constraint_string)
         if m is None:
-            raise ValueError(f"Invalid marker '{constraint_string}'")
+            raise InvalidMarker(f"Invalid marker '{constraint_string}'")
 
         self._operator = m.group(1)
         if self._operator is None:

tests/packages/test_package.py

@@ -9,11 +9,13 @@
 import pytest
 
 from poetry.core.constraints.version import Version
+from poetry.core.constraints.version.exceptions import ParseConstraintError
 from poetry.core.factory import Factory
 from poetry.core.packages.dependency import Dependency
 from poetry.core.packages.dependency_group import DependencyGroup
 from poetry.core.packages.package import Package
 from poetry.core.packages.project_package import ProjectPackage
+from poetry.core.version.exceptions import InvalidVersion
 
 
 if TYPE_CHECKING:
@@ -660,3 +662,20 @@ def test_project_package_hash_not_changed_when_version_is_changed() -> None:
     assert hash(package) == package_hash, "Hash must not change!"
     assert hash(package_clone) == package_hash
     assert package != package_clone
+
+
+def test_package_invalid_version() -> None:
+    with pytest.raises(InvalidVersion) as exc_info:
+        Package("foo", "1.2.3.bogus")
+
+    expected = "Invalid version '1.2.3.bogus' on package foo"
+    assert str(exc_info.value) == expected
+
+
+def test_package_invalid_python_versions() -> None:
+    package = Package("foo", "1.2.3")
+    with pytest.raises(ParseConstraintError) as exc_info:
+        package.python_versions = ">=3.6.y"
+
+    expected = "Invalid python versions '>=3.6.y' on foo (1.2.3)"
+    assert str(exc_info.value) == expected