Support multiple `abi` and `platform` values for `pip download`.

8 files changed, 84 insertions, 46 deletions

diff --git a/docs/html/reference/pip_download.rst b/docs/html/reference/pip_download.rst
index 80acc1942..b600d15e5 100644
--- a/docs/html/reference/pip_download.rst
+++ b/docs/html/reference/pip_download.rst
@@ -197,3 +197,32 @@ Examples
 
          C:\> dir pip-8.1.1-py2.py3-none-any.whl
          pip-8.1.1-py2.py3-none-any.whl
+
+#. Download a package supporting one of several ABIs and platforms.
+    This is useful when fetching wheels for a well-defined interpreter, whose
+    supported ABIs and platforms are known and fixed, different than the one pip is
+    running under.
+
+   .. tab:: Unix/macOS
+
+      .. code-block:: console
+
+         $ python -m pip download \
+            --only-binary=:all: \
+            --platform manylinux1_x86_64 --platform linux_x86_64 --platform any \
+            --python-version 36 \
+            --implementation cp \
+            --abi cp36m --abi cp36 --abi abi3 --abi none \
+            SomePackage
+
+   .. tab:: Windows
+
+      .. code-block:: console
+
+         C:> py -m pip download ^
+            --only-binary=:all: ^
+            --platform manylinux1_x86_64 --platform linux_x86_64 --platform any ^
+            --python-version 36 ^
+            --implementation cp ^
+            --abi cp36m --abi cp36 --abi abi3 --abi none ^
+            SomePackage
diff --git a/news/6121.feature b/news/6121.feature
new file mode 100644
index 000000000..016426e88
--- /dev/null
+++ b/news/6121.feature
@@ -0,0 +1 @@
+Allow comma-separated values for --abi and --platform.
diff --git a/src/pip/_internal/cli/cmdoptions.py b/src/pip/_internal/cli/cmdoptions.py
index e96eac586..fe2fae356 100644
--- a/src/pip/_internal/cli/cmdoptions.py
+++ b/src/pip/_internal/cli/cmdoptions.py
@@ -31,7 +31,7 @@ from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 
 if MYPY_CHECK_RUNNING:
     from optparse import OptionParser, Values
-    from typing import Any, Callable, Dict, Optional, Tuple
+    from typing import Any, Callable, Dict, List, Optional, Tuple
 
     from pip._internal.cli.parser import ConfigOptionParser
 
@@ -588,7 +588,7 @@ abi = partial(
     metavar='abi',
     default=None,
     help=("Only use wheels compatible with Python "
-          "abi <abi>, e.g. 'pypy_41'.  If not specified, then the "
+          "abi <abi>, e.g. 'pypy_41,none'.  If not specified, then the "
           "current interpreter abi tag is used.  Generally "
           "you will need to specify --implementation, "
           "--platform, and --python-version when using "
@@ -606,10 +606,21 @@ def add_target_python_options(cmd_opts):
 
 def make_target_python(options):
     # type: (Values) -> TargetPython
+
+    # abi can be a comma-separated list of values.
+    abis = options.abi  # type: Optional[List[str]]
+    if options.abi:
+        abis = options.abi.split(',')
+
+    # platform can also be a comma-separated list of values.
+    platforms = options.platform  # type: Optional[List[str]]
+    if options.platform:
+        platforms = options.platform.split(',')
+
     target_python = TargetPython(
-        platform=options.platform,
+        platforms=platforms,
         py_version_info=options.python_version,
-        abi=options.abi,
+        abis=abis,
         implementation=options.implementation,
     )
 
diff --git a/src/pip/_internal/models/target_python.py b/src/pip/_internal/models/target_python.py
index ad7e506a6..4593dc854 100644
--- a/src/pip/_internal/models/target_python.py
+++ b/src/pip/_internal/models/target_python.py
@@ -19,9 +19,9 @@ class TargetPython(object):
 
     __slots__ = [
         "_given_py_version_info",
-        "abi",
+        "abis",
         "implementation",
-        "platform",
+        "platforms",
         "py_version",
         "py_version_info",
         "_valid_tags",
@@ -29,23 +29,23 @@ class TargetPython(object):
 
     def __init__(
         self,
-        platform=None,  # type: Optional[str]
+        platforms=None,  # type: Optional[List[str]]
         py_version_info=None,  # type: Optional[Tuple[int, ...]]
-        abi=None,  # type: Optional[str]
+        abis=None,  # type: Optional[List[str]]
         implementation=None,  # type: Optional[str]
     ):
         # type: (...) -> None
         """
-        :param platform: A string or None. If None, searches for packages
-            that are supported by the current system. Otherwise, will find
-            packages that can be built on the platform passed in. These
+        :param platforms: A list of strings or None. If None, searches for
+            packages that are supported by the current system. Otherwise, will
+            find packages that can be built on the platforms passed in. These
             packages will only be downloaded for distribution: they will
             not be built locally.
         :param py_version_info: An optional tuple of ints representing the
             Python version information to use (e.g. `sys.version_info[:3]`).
             This can have length 1, 2, or 3 when provided.
-        :param abi: A string or None. This is passed to compatibility_tags.py's
-            get_supported() function as is.
+        :param abis: A list of strings or None. This is passed to
+            compatibility_tags.py's get_supported() function as is.
         :param implementation: A string or None. This is passed to
             compatibility_tags.py's get_supported() function as is.
         """
@@ -59,9 +59,9 @@ class TargetPython(object):
 
         py_version = '.'.join(map(str, py_version_info[:2]))
 
-        self.abi = abi
+        self.abis = abis
         self.implementation = implementation
-        self.platform = platform
+        self.platforms = platforms
         self.py_version = py_version
         self.py_version_info = py_version_info
 
@@ -80,9 +80,9 @@ class TargetPython(object):
             )
 
         key_values = [
-            ('platform', self.platform),
+            ('platforms', self.platforms),
             ('version_info', display_version),
-            ('abi', self.abi),
+            ('abis', self.abis),
             ('implementation', self.implementation),
         ]
         return ' '.join(
@@ -108,8 +108,8 @@ class TargetPython(object):
 
             tags = get_supported(
                 version=version,
-                platform=self.platform,
-                abi=self.abi,
+                platforms=self.platforms,
+                abis=self.abis,
                 impl=self.implementation,
             )
             self._valid_tags = tags
diff --git a/src/pip/_internal/utils/compatibility_tags.py b/src/pip/_internal/utils/compatibility_tags.py
index 4f21874ec..eb1727e3d 100644
--- a/src/pip/_internal/utils/compatibility_tags.py
+++ b/src/pip/_internal/utils/compatibility_tags.py
@@ -105,9 +105,9 @@ def _get_custom_interpreter(implementation=None, version=None):
 
 def get_supported(
     version=None,  # type: Optional[str]
-    platform=None,  # type: Optional[str]
+    platforms=None,  # type: Optional[List[str]]
     impl=None,  # type: Optional[str]
-    abi=None  # type: Optional[str]
+    abis=None  # type: Optional[List[str]]
 ):
     # type: (...) -> List[Tag]
     """Return a list of supported tags for each version specified in
@@ -115,11 +115,11 @@ def get_supported(
 
     :param version: a string version, of the form "33" or "32",
         or None. The version will be assumed to support our ABI.
-    :param platform: specify the exact platform you want valid
+    :param platform: specify a list of platforms you want valid
         tags for, or None. If None, use the local system platform.
     :param impl: specify the exact implementation you want valid
         tags for, or None. If None, use the local interpreter impl.
-    :param abi: specify the exact abi you want valid
+    :param abis: specify a list of abis you want valid
         tags for, or None. If None, use the local interpreter abi.
     """
     supported = []  # type: List[Tag]
@@ -130,13 +130,10 @@ def get_supported(
 
     interpreter = _get_custom_interpreter(impl, version)
 
-    abis = None  # type: Optional[List[str]]
-    if abi is not None:
-        abis = [abi]
-
-    platforms = None  # type: Optional[List[str]]
-    if platform is not None:
-        platforms = _get_custom_platforms(platform)
+    if platforms and len(platforms) == 1:
+        # Only expand list of platforms if a single platform was provided.
+        # Otherwise, assume that the list provided is comprehensive.
+        platforms = _get_custom_platforms(platforms[0])
 
     is_cpython = (impl or interpreter_name()) == "cp"
     if is_cpython:
diff --git a/tests/unit/test_models_wheel.py b/tests/unit/test_models_wheel.py
index f1fef6f09..05ee74262 100644
--- a/tests/unit/test_models_wheel.py
+++ b/tests/unit/test_models_wheel.py
@@ -76,7 +76,7 @@ class TestWheelFile(object):
         Wheels built for macOS 10.6 are supported on 10.9
         """
         tags = compatibility_tags.get_supported(
-            '27', platform='macosx_10_9_intel', impl='cp'
+            '27', platforms=['macosx_10_9_intel'], impl='cp'
         )
         w = Wheel('simple-0.1-cp27-none-macosx_10_6_intel.whl')
         assert w.supported(tags=tags)
@@ -88,7 +88,7 @@ class TestWheelFile(object):
         Wheels built for macOS 10.9 are not supported on 10.6
         """
         tags = compatibility_tags.get_supported(
-            '27', platform='macosx_10_6_intel', impl='cp'
+            '27', platforms=['macosx_10_6_intel'], impl='cp'
         )
         w = Wheel('simple-0.1-cp27-none-macosx_10_9_intel.whl')
         assert not w.supported(tags=tags)
@@ -98,22 +98,22 @@ class TestWheelFile(object):
         Multi-arch wheels (intel) are supported on components (i386, x86_64)
         """
         universal = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_universal', impl='cp'
+            '27', platforms=['macosx_10_5_universal'], impl='cp'
         )
         intel = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_intel', impl='cp'
+            '27', platforms=['macosx_10_5_intel'], impl='cp'
         )
         x64 = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_x86_64', impl='cp'
+            '27', platforms=['macosx_10_5_x86_64'], impl='cp'
         )
         i386 = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_i386', impl='cp'
+            '27', platforms=['macosx_10_5_i386'], impl='cp'
         )
         ppc = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_ppc', impl='cp'
+            '27', platforms=['macosx_10_5_ppc'], impl='cp'
         )
         ppc64 = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_ppc64', impl='cp'
+            '27', platforms=['macosx_10_5_ppc64'], impl='cp'
         )
 
         w = Wheel('simple-0.1-cp27-none-macosx_10_5_intel.whl')
@@ -136,10 +136,10 @@ class TestWheelFile(object):
         Single-arch wheels (x86_64) are not supported on multi-arch (intel)
         """
         universal = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_universal', impl='cp'
+            '27', platforms=['macosx_10_5_universal'], impl='cp'
         )
         intel = compatibility_tags.get_supported(
-            '27', platform='macosx_10_5_intel', impl='cp'
+            '27', platforms=['macosx_10_5_intel'], impl='cp'
         )
 
         w = Wheel('simple-0.1-cp27-none-macosx_10_5_i386.whl')
diff --git a/tests/unit/test_target_python.py b/tests/unit/test_target_python.py
index 0dc2af22b..a314988eb 100644
--- a/tests/unit/test_target_python.py
+++ b/tests/unit/test_target_python.py
@@ -45,16 +45,16 @@ class TestTargetPython:
         ({}, ''),
         (dict(py_version_info=(3, 6)), "version_info='3.6'"),
         (
-            dict(platform='darwin', py_version_info=(3, 6)),
-            "platform='darwin' version_info='3.6'",
+            dict(platforms=['darwin'], py_version_info=(3, 6)),
+            "platforms=['darwin'] version_info='3.6'",
         ),
         (
             dict(
-                platform='darwin', py_version_info=(3, 6), abi='cp36m',
+                platforms=['darwin'], py_version_info=(3, 6), abis=['cp36m'],
                 implementation='cp'
             ),
             (
-                "platform='darwin' version_info='3.6' abi='cp36m' "
+                "platforms=['darwin'] version_info='3.6' abis=['cp36m'] "
                 "implementation='cp'"
             ),
         ),
diff --git a/tests/unit/test_utils_compatibility_tags.py b/tests/unit/test_utils_compatibility_tags.py
index 12c8da453..64f59a2f9 100644
--- a/tests/unit/test_utils_compatibility_tags.py
+++ b/tests/unit/test_utils_compatibility_tags.py
@@ -63,7 +63,7 @@ class TestManylinux2010Tags(object):
         Specifying manylinux2010 implies manylinux1.
         """
         groups = {}
-        supported = compatibility_tags.get_supported(platform=manylinux2010)
+        supported = compatibility_tags.get_supported(platforms=[manylinux2010])
         for tag in supported:
             groups.setdefault(
                 (tag.interpreter, tag.abi), []
@@ -87,7 +87,7 @@ class TestManylinux2014Tags(object):
         Specifying manylinux2014 implies manylinux2010/manylinux1.
         """
         groups = {}
-        supported = compatibility_tags.get_supported(platform=manylinuxA)
+        supported = compatibility_tags.get_supported(platforms=[manylinuxA])
         for tag in supported:
             groups.setdefault(
                 (tag.interpreter, tag.abi), []