Only install packages for current python version

- Still resolve all packages to lockfile
- Fixes #1952

Signed-off-by: Dan Ryan <dan@danryan.co>

pipenv/patched/notpip/index.py

@@ -711,7 +711,9 @@ def _link_package_versions(self, link, search, ignore_compatibility=True):
                          link.filename, link.requires_python)
             support_this_python = True
 
-        if not support_this_python and not ignore_compatibility:
+        # Normally we would keep this the same, but instead we always
+        # want to include only things that support this python version
+        if not support_this_python:   # and not ignore_compatibility:
             logger.debug("The package %s is incompatible with the python"
                          "version in use. Acceptable python versions are:%s",
                          link, link.requires_python)

pipenv/patched/piptools/repositories/pypi.py

@@ -168,18 +168,28 @@ def get_json_dependencies(self, ireq):
         def gen(ireq):
             if self.DEFAULT_INDEX_URL in self.finder.index_urls:
 
-                url = 'https://pypi.org/pypi/{0}/json'.format(ireq.req.name)
+                url = 'https://pypi.org/pypi/{0}/{1}/json'.format(
+                    ireq.req.name,
+                    str(ireq.req.specifier),
+                )
                 r = self.session.get(url)
+                if not r:
+                    r = self.session.get(
+                        'https://pypi.org/pypi/{0}/json'.format(
+                            ireq.req.name,
+                        )
+                    )
+                json = r.json()
 
                 # TODO: Latest isn't always latest.
-                latest = list(r.json()['releases'].keys())[-1]
-                if str(ireq.req.specifier) == '=={0}'.format(latest):
-
-                    for requires in r.json().get('info', {}).get('requires_dist', {}):
-                        i = InstallRequirement.from_line(requires)
-
-                        if 'extra' not in repr(i.markers):
-                            yield i
+                version = json['version']
+                if str(ireq.req.specifier) == '=={0}'.format(version):
+                    dependencies = json.get('info', {}).get('requires_dist', {})
+                    for dep in dependencies:
+                        req = InstallRequirement.from_line(dep)
+
+                        if 'extra' not in repr(req.markers):
+                            yield req
 
         try:
             if ireq not in self._json_dep_cache:

tasks/vendoring/patches/patched/_post-pip-update-repository-finder.patch

@@ -0,0 +1,15 @@
+diff --git a/pipenv/patched/notpip/index.py b/pipenv/patched/notpip/index.py
+index bf1cba9..42968a5 100644
+--- a/pipenv/patched/notpip/index.py
++++ b/pipenv/patched/notpip/index.py
+@@ -711,7 +711,9 @@ class PackageFinder(object):
+                          link.filename, link.requires_python)
+             support_this_python = True
+
+-        if not support_this_python and not ignore_compatibility:
++        # Normally we would keep this the same, but instead we always
++        # want to include only things that support this python version
++        if not support_this_python:   # and not ignore_compatibility:
+             logger.debug("The package %s is incompatible with the python"
+                          "version in use. Acceptable python versions are:%s",
+                          link, link.requires_python)

tasks/vendoring/patches/patched/piptools-update-json-search.patch

@@ -0,0 +1,42 @@
+diff --git a/pipenv/patched/piptools/repositories/pypi.py b/pipenv/patched/piptools/repositories/pypi.py
+index e503197..ce78e8a 100644
+--- a/pipenv/patched/piptools/repositories/pypi.py
++++ b/pipenv/patched/piptools/repositories/pypi.py
+@@ -168,18 +168,28 @@ class PyPIRepository(BaseRepository):
+         def gen(ireq):
+             if self.DEFAULT_INDEX_URL in self.finder.index_urls:
+
+-                url = 'https://pypi.org/pypi/{0}/json'.format(ireq.req.name)
++                url = 'https://pypi.org/pypi/{0}/{1}/json'.format(
++                    ireq.req.name,
++                    str(ireq.req.specifier),
++                )
+                 r = self.session.get(url)
++                if not r:
++                    r = self.session.get(
++                        'https://pypi.org/pypi/{0}/json'.format(
++                            ireq.req.name,
++                        )
++                    )
++                json = r.json()
+
+                 # TODO: Latest isn't always latest.
+-                latest = list(r.json()['releases'].keys())[-1]
+-                if str(ireq.req.specifier) == '=={0}'.format(latest):
+-
+-                    for requires in r.json().get('info', {}).get('requires_dist', {}):
+-                        i = InstallRequirement.from_line(requires)
+-
+-                        if 'extra' not in repr(i.markers):
+-                            yield i
++                version = json['version']
++                if str(ireq.req.specifier) == '=={0}'.format(version):
++                    dependencies = json.get('info', {}).get('requires_dist', {})
++                    for dep in dependencies:
++                        req = InstallRequirement.from_line(dep)
++
++                        if 'extra' not in repr(req.markers):
++                            yield req
+
+         try:
+             if ireq not in self._json_dep_cache: