Handle inspection for package without dependencies and no setup.py files (#2615)

* inspection: improve handling of sdist packages

This change ensures that inspection does not fail pre-maturely if
source does not contain a setup.py and no dependencies were
discovered.

Resolves: #2603

* inspection: add tests for package info discovery

poetry/inspection/info.py

@@ -176,10 +176,11 @@ class PackageInfo:
 
 
         :param dist: The distribution instance to parse information from.
         :param dist: The distribution instance to parse information from.
         """
         """
+        requirements = None
+
         if dist.requires_dist:
         if dist.requires_dist:
             requirements = list(dist.requires_dist)
             requirements = list(dist.requires_dist)
         else:
         else:
-            requirements = []
             requires = Path(dist.filename) / "requires.txt"
             requires = Path(dist.filename) / "requires.txt"
             if requires.exists():
             if requires.exists():
                 with requires.open(encoding="utf-8") as f:
                 with requires.open(encoding="utf-8") as f:
@@ -190,7 +191,7 @@ class PackageInfo:
             version=dist.version,
             version=dist.version,
             summary=dist.summary,
             summary=dist.summary,
             platform=dist.supported_platforms,
             platform=dist.supported_platforms,
-            requires_dist=requirements or None,
+            requires_dist=requirements,
             requires_python=dist.requires_python,
             requires_python=dist.requires_python,
         )
         )
 
 
@@ -234,8 +235,8 @@ class PackageInfo:
 
 
         with temporary_directory() as tmp:
         with temporary_directory() as tmp:
             tmp = Path(tmp)
             tmp = Path(tmp)
-            with context(str(path)) as archive:
-                archive.extractall(str(tmp))
+            with context(path.as_posix()) as archive:
+                archive.extractall(tmp.as_posix())
 
 
             # a little bit of guess work to determine the directory we care about
             # a little bit of guess work to determine the directory we care about
             elements = list(tmp.glob("*"))
             elements = list(tmp.glob("*"))
@@ -244,6 +245,8 @@ class PackageInfo:
                 sdist_dir = elements[0]
                 sdist_dir = elements[0]
             else:
             else:
                 sdist_dir = tmp / path.name.rstrip(suffix)
                 sdist_dir = tmp / path.name.rstrip(suffix)
+                if not sdist_dir.is_dir():
+                    sdist_dir = tmp
 
 
             # now this is an unpacked directory we know how to deal with
             # now this is an unpacked directory we know how to deal with
             new_info = cls.from_directory(path=sdist_dir)
             new_info = cls.from_directory(path=sdist_dir)
@@ -313,7 +316,7 @@ class PackageInfo:
             yield Path(d)
             yield Path(d)
 
 
     @classmethod
     @classmethod
-    def from_metadata(cls, path):  # type: (Union[str, Path]) -> PackageInfo
+    def from_metadata(cls, path):  # type: (Union[str, Path]) -> Optional[PackageInfo]
         """
         """
         Helper method to parse package information from an unpacked metadata directory.
         Helper method to parse package information from an unpacked metadata directory.
 
 
@@ -322,23 +325,31 @@ class PackageInfo:
         path = Path(path)
         path = Path(path)
 
 
         if path.suffix in {".dist-info", ".egg-info"}:
         if path.suffix in {".dist-info", ".egg-info"}:
-            directories = [path.suffix]
+            directories = [path]
         else:
         else:
             directories = cls._find_dist_info(path=path)
             directories = cls._find_dist_info(path=path)
 
 
         for directory in directories:
         for directory in directories:
             try:
             try:
                 if directory.suffix == ".egg-info":
                 if directory.suffix == ".egg-info":
-                    dist = pkginfo.UnpackedSDist(str(directory))
+                    dist = pkginfo.UnpackedSDist(directory.as_posix())
                 elif directory.suffix == ".dist-info":
                 elif directory.suffix == ".dist-info":
-                    dist = pkginfo.Wheel(str(directory))
+                    dist = pkginfo.Wheel(directory.as_posix())
                 else:
                 else:
                     continue
                     continue
-                info = cls._from_distribution(dist=dist)
-                if info:
-                    return info
+                break
             except ValueError:
             except ValueError:
-                pass
+                continue
+        else:
+            try:
+                # handle PKG-INFO in unpacked sdist root
+                dist = pkginfo.UnpackedSDist(path.as_posix())
+            except ValueError:
+                return
+
+        info = cls._from_distribution(dist=dist)
+        if info:
+            return info
 
 
     @classmethod
     @classmethod
     def from_package(cls, package):  # type: (Package) -> PackageInfo
     def from_package(cls, package):  # type: (Package) -> PackageInfo
@@ -355,7 +366,7 @@ class PackageInfo:
 
 
         return cls(
         return cls(
             name=package.name,
             name=package.name,
-            version=package.version,
+            version=str(package.version),
             summary=package.description,
             summary=package.description,
             platform=package.platform,
             platform=package.platform,
             requires_dist=list(requires),
             requires_dist=list(requires),
@@ -395,6 +406,14 @@ class PackageInfo:
         """
         """
         path = Path(path)
         path = Path(path)
 
 
+        current_dir = os.getcwd()
+
+        info = cls.from_metadata(path)
+
+        if info and info.requires_dist is not None:
+            # return only if requirements are discovered
+            return info
+
         setup_py = path.joinpath("setup.py")
         setup_py = path.joinpath("setup.py")
 
 
         project_package = cls._get_poetry_package(path)
         project_package = cls._get_poetry_package(path)
@@ -402,17 +421,12 @@ class PackageInfo:
             return cls.from_package(project_package)
             return cls.from_package(project_package)
 
 
         if not setup_py.exists():
         if not setup_py.exists():
+            if not allow_build and info:
+                # we discovered PkgInfo but no requirements were listed
+                return info
             # this means we cannot do anything else here
             # this means we cannot do anything else here
             raise PackageInfoError(path)
             raise PackageInfoError(path)
 
 
-        current_dir = os.getcwd()
-
-        info = cls.from_metadata(path)
-
-        if info and info.requires_dist is not None:
-            # return only if requirements are discovered
-            return info
-
         if not allow_build:
         if not allow_build:
             return cls.from_setup_py(path=path)
             return cls.from_setup_py(path=path)
 
 

tests/fixtures/inspection/demo/pyproject.toml

+[tool.poetry]
+name = "demo"
+version = "0.1.0"
+description = ""
+authors = ["Sébastien Eustace <sebastien@eustace.io>"]
+
+[tool.poetry.dependencies]
+python = "~2.7 || ^3.4"
+pendulum = ">=1.4.4"
+cleo = {version = "*", optional = true}
+tomlkit = {version = "*", optional = true}
+
+[tool.poetry.extras]
+foo = ["cleo"]
+bar = ["tomlkit"]
+
+[tool.poetry.dev-dependencies]
+pytest = "^3.0"

tests/fixtures/inspection/demo_no_setup_pkg_info_no_deps/PKG-INFO

+Metadata-Version: 1.0
+Name: demo
+Version: 0.1.0
+Summary: Demo project.
+Home-page: https://github.com/demo/demo
+Author: Sébastien Eustace
+Author-email: sebastien@eustace.io
+License: MIT
+Description: UNKNOWN
+Platform: UNKNOWN

tests/fixtures/inspection/demo_no_setup_pkg_info_no_deps/pyproject.toml

+# this was copied over and modified from orjson project's pyproject.toml
+# https://github.com/ijl/orjson/blob/master/pyproject.toml
+[project]
+name = "demo"
+repository = "https://github.com/demo/demo"
+
+[build-system]
+build-backend = "maturin"
+requires = ["maturin>=0.8.1,<0.9"]
+
+[tool.maturin]
+manylinux = "off"
+sdist-include = ["Cargo.lock", "json/**/*"]
+strip = "on"
+
+[tool.black]
+line-length = 88
+target-version = ['py36', 'py37', 'py38']
+include = '\.pyi?$'

tests/fixtures/inspection/demo_only_requires_txt.egg-info/PKG-INFO

+Metadata-Version: 1.0
+Name: demo
+Version: 0.1.0
+Summary: Demo project.
+Home-page: https://github.com/demo/demo
+Author: Sébastien Eustace
+Author-email: sebastien@eustace.io
+License: MIT
+Description: UNKNOWN
+Platform: UNKNOWN

tests/fixtures/inspection/demo_only_requires_txt.egg-info/requires.txt

+cleo; extra == "foo"
+pendulum (>=1.4.4)
+tomlkit; extra == "bar"

tests/fixtures/inspection/demo_only_setup/setup.py

+# -*- coding: utf-8 -*-
+
+from setuptools import setup
+
+
+kwargs = dict(
+    name="demo",
+    license="MIT",
+    version="0.1.0",
+    description="Demo project.",
+    author="Sébastien Eustace",
+    author_email="sebastien@eustace.io",
+    url="https://github.com/demo/demo",
+    packages=["my_package"],
+    install_requires=[
+        'cleo; extra == "foo"',
+        "pendulum (>=1.4.4)",
+        'tomlkit; extra == "bar"',
+    ],
+)
+
+
+setup(**kwargs)

tests/inspection/test_info.py

+import pytest
+
+from poetry.inspection.info import PackageInfo
+from poetry.utils._compat import PY35
+from poetry.utils._compat import Path
+
+
+FIXTURE_DIR_BASE = Path(__file__).parent.parent / "fixtures"
+FIXTURE_DIR_INSPECTIONS = FIXTURE_DIR_BASE / "inspection"
+
+
+@pytest.fixture
+def demo_sdist():  # type: () -> Path
+    return FIXTURE_DIR_BASE / "distributions" / "demo-0.1.0.tar.gz"
+
+
+@pytest.fixture
+def demo_wheel():  # type: () -> Path
+    return FIXTURE_DIR_BASE / "distributions" / "demo-0.1.0-py2.py3-none-any.whl"
+
+
+def demo_check_info(info):  # type: (PackageInfo) -> None
+    assert info.name == "demo"
+    assert info.version == "0.1.0"
+    assert set(info.requires_dist) == {
+        'cleo; extra == "foo"',
+        "pendulum (>=1.4.4)",
+        'tomlkit; extra == "bar"',
+    }
+
+
+def test_info_from_sdist(demo_sdist):
+    info = PackageInfo.from_sdist(demo_sdist)
+    demo_check_info(info)
+
+
+def test_info_from_wheel(demo_wheel):
+    info = PackageInfo.from_wheel(demo_wheel)
+    demo_check_info(info)
+
+
+def test_info_from_bdist(demo_wheel):
+    info = PackageInfo.from_bdist(demo_wheel)
+    demo_check_info(info)
+
+
+def test_info_from_poetry_directory():
+    info = PackageInfo.from_directory(FIXTURE_DIR_INSPECTIONS / "demo")
+    demo_check_info(info)
+
+
+def test_info_from_requires_txt():
+    info = PackageInfo.from_metadata(
+        FIXTURE_DIR_INSPECTIONS / "demo_only_requires_txt.egg-info"
+    )
+    demo_check_info(info)
+
+
+@pytest.mark.skipif(not PY35, reason="Parsing of setup.py is skipped for Python < 3.5")
+def test_info_from_setup_py():
+    info = PackageInfo.from_setup_py(FIXTURE_DIR_INSPECTIONS / "demo_only_setup")
+    demo_check_info(info)
+
+
+def test_info_no_setup_pkg_info_no_deps():
+    info = PackageInfo.from_directory(
+        FIXTURE_DIR_INSPECTIONS / "demo_no_setup_pkg_info_no_deps"
+    )
+    assert info.name == "demo"
+    assert info.version == "0.1.0"
+    assert info.requires_dist is None