Do not crash when manifest files are empty

Signed-off-by: Tushar Goel <[email protected]>

Author: TG1999

src/python_inspector/api.py

@@ -83,7 +83,14 @@ def resolver_api(
     """
     Resolve the dependencies for the package requirements listed in one or
     more ``requirement_files``, one or more ``specifiers`` and one setuptools
-    ``setup_py_file`` file and save the results as JSON to FILE.
+    ``setup_py_file`` file.
+
+    Resolve the dependencies for the requested ``python_version`` PYVER and
+    ``operating_system`` OS combination defaulting Python version 3.8 and
+    linux OS.
+
+    Download from the provided PyPI simple index_urls INDEX(s) URLs defaulting
+    to PyPI.org
     """
 
     if verbose:
@@ -198,7 +205,11 @@ def resolver_api(
         )
 
     if not direct_dependencies:
-        raise Exception("Error: no requirements requested.")
+        return Resolution(
+            packages=[],
+            resolution={},
+            files=files,
+        )
 
     if verbose:
         printer("direct_dependencies:")
@@ -266,7 +277,7 @@ def resolver_api(
         packages=packages,
         resolution=resolution,
         files=files,
-    ).to_dict()
+    )
 
 
 def resolve(
@@ -345,6 +356,9 @@ def get_resolved_dependencies(
 def get_requirements_from_direct_dependencies(
     direct_dependencies: List[DependentPackage], environment_marker: Dict
 ) -> List[Requirement]:
+    """
+    Yield Requirements from a list of DependentPackages.
+    """
     for dependency in direct_dependencies:
         # FIXME We are skipping editable requirements
         # and other pip options for now

src/python_inspector/resolution.py

@@ -81,17 +81,9 @@ def get_requirements_from_distribution(
     if not os.path.exists(location):
         return []
     reqs = []
-    try:
-        for package_data in handler.parse(location):
-            dependencies = package_data.dependencies
-            reqs.extend(get_requirements_from_dependencies(dependencies=dependencies))
-    except Exception as e:
-        import subprocess
-
-        subprocess.check_call(["zip", "-T", location])
-        raise Exception(
-            f"Could not get requirements from pypi package at: {location!r}: {e}"
-        ) from e
+    for package_data in handler.parse(location):
+        dependencies = package_data.dependencies
+    reqs.extend(get_requirements_from_dependencies(dependencies=dependencies))
     return reqs
 
 

src/python_inspector/resolve_cli.py

@@ -253,9 +253,9 @@ def resolve_dependencies(
         )
         output = dict(
             headers=headers,
-            resolved_dependencies_graph=resolution_result.get("resolution"),
-            files=resolution_result.get("files"),
-            packages=resolution_result.get("packages"),
+            resolved_dependencies_graph=resolution_result.resolution,
+            files=resolution_result.files,
+            packages=resolution_result.packages,
         )
         write_output_in_file(
             output=output,

src/python_inspector/setup_py_live_eval.py

@@ -60,6 +60,8 @@ def iter_requirements(level, extras, setup_file):
             with open(setup_file) as sf:
                 exec(sf.read(), g)
             sys.path.pop()
+            # removing this assertion since it is not true for all cases
+            # for example when setuptools.setup() is called instead of setup()
 
     mock_args, mock_kwargs = mock_setup.call_args
     install_requires = mock_kwargs.get("install_requires", install_requires)

tests/test_api.py

@@ -31,7 +31,7 @@ def test_api_with_specifier():
                     specifiers=["flask==2.1.2"],
                     python_version="3.10",
                     operating_system="linux",
-                )
+                ).to_dict()
             )
         )
     check_json_results(
@@ -52,7 +52,7 @@ def test_api_with_specifier_pdt():
                     python_version="3.10",
                     operating_system="linux",
                     pdt_output=True,
-                )
+                ).to_dict()
             )
         )
     check_json_results(
@@ -73,7 +73,7 @@ def test_api_with_requirement_file():
                     python_version="3.10",
                     operating_system="linux",
                     requirement_files=[requirement_file],
-                )
+                ).to_dict()
             )
         )
     check_json_results(

tests/test_cli.py

@@ -346,16 +346,15 @@ def test_passing_of_netrc_file_that_does_not_exist():
     run_cli(options=options, expected_rc=2)
 
 
-def test_passing_of_wrong_requirements_file():
+def test_passing_of_empty_requirements_file():
     test_file = test_env.get_temp_file(file_name="pdt.txt", extension="")
     with open(test_file, "w") as f:
         f.write("")
     test_file_2 = test_env.get_temp_file(file_name="setup.py", extension="")
     with open(test_file_2, "w") as f:
         f.write("")
     options = ["--requirement", test_file, "--json", "-", "--requirement", test_file_2]
-    result = run_cli(options=options, expected_rc=1)
-    assert "Error: no requirements requested" in result.output
+    run_cli(options=options, expected_rc=0)
 
 
 def test_passing_of_no_json_output_flag():