Resolve versionless dependencies #78

src/python_inspector/resolution.py

@@ -192,10 +192,11 @@ def is_valid_version(
     """
     Return True if the parsed_version is valid for the given identifier.
     """
-    if (
-        any(parsed_version not in r.specifier for r in requirements[identifier])
-        or parsed_version in bad_versions
-    ):
+    if parsed_version in bad_versions:
+        return False
+    if any(parsed_version not in r.specifier for r in requirements[identifier]):
+        if all(not r.specifier for r in requirements[identifier]):
+            return True
         return False
     return True
 
@@ -453,16 +454,22 @@ def get_candidates(
         """
         Generate candidates for the given identifier. Overridden.
         """
+        valid_versions = []
         for version in all_versions:
             parsed_version = parse_version(version)
-            if not is_valid_version(
+            if is_valid_version(
                 parsed_version=parsed_version,
                 requirements=requirements,
                 identifier=identifier,
                 bad_versions=bad_versions,
             ):
-                continue
-            yield Candidate(name=name, version=parsed_version, extras=extras)
+                valid_versions.append(parsed_version)
+        if all(version.is_prerelease for version in valid_versions):
+            pass
+        else:
+            valid_versions = [version for version in valid_versions if not version.is_prerelease]
+        for version in valid_versions:
+            yield Candidate(name=name, version=version, extras=extras)
 
     def _iter_matches(
         self,
@@ -504,7 +511,11 @@ def find_matches(
 
     def is_satisfied_by(self, requirement: Requirement, candidate: Candidate) -> bool:
         """Whether the given requirement can be satisfied by a candidate. Overridden."""
-        return candidate.version in requirement.specifier
+        if candidate.version in requirement.specifier:
+            return True
+        elif not requirement.specifier:
+            return True
+        return False
 
     def _iter_dependencies(self, candidate: Candidate) -> Generator[Requirement, None, None]:
         """

tests/data/azure-devops.req.txt

@@ -0,0 +1,3 @@
+azure-devops
+azure-storage-blob
+click

tests/test_cli.py

@@ -162,6 +162,24 @@ def test_cli_with_environment_marker_and_complex_ranges():
     )
 
 
+@pytest.mark.online
+def test_cli_with_azure_devops():
+    requirements_file = test_env.get_test_loc("azure-devops.req.txt")
+    expected_file = test_env.get_test_loc("azure-devops.req-expected.json", must_exist=False)
+    extra_options = [
+        "--operating-system",
+        "linux",
+        "--python-version",
+        "38",
+    ]
+    check_requirements_resolution(
+        requirements_file=requirements_file,
+        expected_file=expected_file,
+        extra_options=extra_options,
+        regen=REGEN_TEST_FIXTURES,
+    )
+
+
 @pytest.mark.online
 def test_cli_with_multiple_index_url_and_tilde_req_with_max_rounds():
     expected_file = test_env.get_test_loc("tilde_req-expected.json", must_exist=False)