Add new feature toggle for VCS dependency resolution

- Fixes #3577

Signed-off-by: Dan Ryan <[email protected]>

news/3577.feature.rst

@@ -0,0 +1 @@
+Added a new environment variable, ``PIPENV_RESOLVE_VCS``, to toggle dependency resolution off for non-editable VCS, file, and URL based dependencies.

pipenv/core.py

@@ -1388,6 +1388,8 @@ def pip_install(
             src_dir = os.environ["PIP_SRC"]
             src = ["--src", os.environ["PIP_SRC"]]
         if not requirement.editable:
+            # Leave this off becauase old lockfiles don't have all deps included
+            # TODO: When can it be turned back on?
             no_deps = False
 
         if src_dir is not None:
@@ -1441,7 +1443,7 @@ def pip_install(
         ignore_hashes = True if not requirement.hashes else ignore_hashes
         line = requirement.as_line(include_hashes=not ignore_hashes)
         line = "{0} {1}".format(line, " ".join(src))
-        if environments.is_verbose()
+        if environments.is_verbose():
             click.echo(
                 "Writing first requirement line to temporary file: {0!r}".format(line),
                 err=True

pipenv/environments.py

@@ -234,6 +234,15 @@ def _is_env_truthy(name):
 NOTE: This only affects the ``install`` and ``uninstall`` commands.
 """
 
+PIPENV_RESOLVE_VCS = _is_env_truthy(os.environ.get("PIPENV_RESOLVE_VCS", True))
+"""Tells Pipenv whether to resolve all VCS dependencies in full.
+
+As of Pipenv 2018.11.26, only editable VCS dependencies were resolved in full.
+To retain this behavior and avoid handling any conflicts that arise from the new
+approach, you may set this to '0', 'off', or 'false'.
+"""
+
+
 PIPENV_PYUP_API_KEY = os.environ.get(
     "PIPENV_PYUP_API_KEY", "1ab8d58f-5122e025-83674263-bc1e79e0"
 )

pipenv/utils.py

@@ -30,7 +30,9 @@
 import parse
 
 from . import environments
-from .exceptions import PipenvUsageError, RequirementError, PipenvCmdError
+from .exceptions import (
+    PipenvUsageError, RequirementError, PipenvCmdError, ResolutionFailure
+)
 from .pep508checker import lookup
 from .vendor.urllib3 import util as urllib3_util
 
@@ -419,6 +421,7 @@ def get_deps_from_line(cls, line):
     def get_deps_from_req(cls, req):
         # type: (Requirement) -> Tuple[Set[str], Dict[str, Dict[str, Union[str, bool, List[str]]]]]
         from requirementslib.models.utils import _requirement_to_str_lowercase_name
+        from requirementslib.utils import is_installable_dir
         constraints = set()  # type: Set[str]
         locked_deps = dict()  # type: Dict[str, Dict[str, Union[str, bool, List[str]]]]
         if req.is_file_or_url or req.is_vcs and not req.is_wheel:
@@ -437,7 +440,16 @@ def get_deps_from_req(cls, req):
                 raise RequirementError(req=req)
             setup_info = req.req.setup_info
             locked_deps[pep423_name(name)] = entry
-            requirements = [v for v in getattr(setup_info, "requires", {}).values()]
+            requirements = []
+            # Allow users to toggle resolution off for non-editable VCS packages
+            # but leave it on for local, installable folders on the filesystem
+            if environments.PIPENV_RESOLVE_VCS or not (
+                req.editable or (
+                    req.is_file_or_url and parsed_line.is_local and
+                    is_installable_dir(parsed_line.path)
+                )
+            ):
+                requirements = [v for v in getattr(setup_info, "requires", {}).values()]
             for r in requirements:
                 if getattr(r, "url", None) and not getattr(r, "editable", False):
                     if r is not None: