feat: fallback to gather metadata via pep517 if reading as Poetry pro…

…ject raises RuntimeError

src/poetry/inspection/info.py

@@ -457,7 +457,9 @@ def _get_poetry_package(path: Path) -> ProjectPackage | None:
         # Note: we ignore any setup.py file at this step
         # TODO: add support for handling non-poetry PEP-517 builds
         if PyProjectTOML(path.joinpath("pyproject.toml")).is_poetry_project():
-            return Factory().create_poetry(path).package
+            with contextlib.suppress(RuntimeError):
+                return Factory().create_poetry(path).package
+
         return None
 
     @classmethod

src/poetry/installation/executor.py

@@ -548,32 +548,37 @@ def _install_directory(self, operation: Install | Update) -> int:
                 self._env.pip_version
                 < self._env.pip_version.__class__.from_parts(19, 0, 0)
             )
-            package_poetry = Factory().create_poetry(pyproject.file.path.parent)
 
-            builder: Builder
-            if package.develop and not package_poetry.package.build_script:
-                from poetry.masonry.builders.editable import EditableBuilder
-
-                # This is a Poetry package in editable mode
-                # we can use the EditableBuilder without going through pip
-                # to install it, unless it has a build script.
-                builder = EditableBuilder(package_poetry, self._env, NullIO())
-                builder.build()
-
-                return 0
-            elif legacy_pip or package_poetry.package.build_script:
-                from poetry.core.masonry.builders.sdist import SdistBuilder
-
-                # We need to rely on creating a temporary setup.py
-                # file since the version of pip does not support
-                # build-systems
-                # We also need it for non-PEP-517 packages
-                builder = SdistBuilder(package_poetry)
-
-                with builder.setup_py():
-                    if package.develop:
-                        return self.pip_install(req, upgrade=True, editable=True)
-                    return self.pip_install(req, upgrade=True)
+            try:
+                package_poetry = Factory().create_poetry(pyproject.file.path.parent)
+            except RuntimeError:
+                package_poetry = None
+
+            if package_poetry is not None:
+                builder: Builder
+                if package.develop and not package_poetry.package.build_script:
+                    from poetry.masonry.builders.editable import EditableBuilder
+
+                    # This is a Poetry package in editable mode
+                    # we can use the EditableBuilder without going through pip
+                    # to install it, unless it has a build script.
+                    builder = EditableBuilder(package_poetry, self._env, NullIO())
+                    builder.build()
+
+                    return 0
+                elif legacy_pip or package_poetry.package.build_script:
+                    from poetry.core.masonry.builders.sdist import SdistBuilder
+
+                    # We need to rely on creating a temporary setup.py
+                    # file since the version of pip does not support
+                    # build-systems
+                    # We also need it for non-PEP-517 packages
+                    builder = SdistBuilder(package_poetry)
+
+                    with builder.setup_py():
+                        if package.develop:
+                            return self.pip_install(req, upgrade=True, editable=True)
+                        return self.pip_install(req, upgrade=True)
 
         if package.develop:
             return self.pip_install(req, upgrade=True, editable=True)

src/poetry/installation/pip_installer.py

@@ -231,39 +231,44 @@ def install_directory(self, package: Package) -> str | int:
             # so we need to check the version of pip to know
             # if we can rely on the build system
             legacy_pip = self._env.pip_version < Version.from_parts(19, 0, 0)
-            package_poetry = Factory().create_poetry(pyproject.file.path.parent)
-
-            builder: Builder
-            if package.develop and not package_poetry.package.build_script:
-                from poetry.masonry.builders.editable import EditableBuilder
-
-                # This is a Poetry package in editable mode
-                # we can use the EditableBuilder without going through pip
-                # to install it, unless it has a build script.
-                builder = EditableBuilder(package_poetry, self._env, NullIO())
-                builder.build()
-
-                return 0
-            elif legacy_pip or package_poetry.package.build_script:
-                from poetry.core.masonry.builders.sdist import SdistBuilder
-
-                # We need to rely on creating a temporary setup.py
-                # file since the version of pip does not support
-                # build-systems
-                # We also need it for non-PEP-517 packages
-                builder = SdistBuilder(package_poetry)
-
-                with builder.setup_py():
-                    if package.develop:
+
+            try:
+                package_poetry = Factory().create_poetry(pyproject.file.path.parent)
+            except RuntimeError:
+                package_poetry = None
+
+            if package_poetry is not None:
+                builder: Builder
+                if package.develop and not package_poetry.package.build_script:
+                    from poetry.masonry.builders.editable import EditableBuilder
+
+                    # This is a Poetry package in editable mode
+                    # we can use the EditableBuilder without going through pip
+                    # to install it, unless it has a build script.
+                    builder = EditableBuilder(package_poetry, self._env, NullIO())
+                    builder.build()
+
+                    return 0
+                elif legacy_pip or package_poetry.package.build_script:
+                    from poetry.core.masonry.builders.sdist import SdistBuilder
+
+                    # We need to rely on creating a temporary setup.py
+                    # file since the version of pip does not support
+                    # build-systems
+                    # We also need it for non-PEP-517 packages
+                    builder = SdistBuilder(package_poetry)
+
+                    with builder.setup_py():
+                        if package.develop:
+                            return pip_install(
+                                path=req,
+                                environment=self._env,
+                                upgrade=True,
+                                editable=True,
+                            )
                         return pip_install(
-                            path=req,
-                            environment=self._env,
-                            upgrade=True,
-                            editable=True,
+                            path=req, environment=self._env, deps=False, upgrade=True
                         )
-                    return pip_install(
-                        path=req, environment=self._env, deps=False, upgrade=True
-                    )
 
         if package.develop:
             return pip_install(