Implement macos_wheel platform (RobotLocomotion#17301)

* Implement macos_wheel platform

Add support for the recently added "macos_wheel" target/platform.
Add ability to override the platform on macOS, which finishes
implementing the "macos_wheel" target/platform that was recently
introduced. Implement support for the same. This should, with a proper
environment, allow Drake to be built in a mode that can be used to
produce a wheel.

(Scripts to actually perform such a build, and particularly to establish
the aforementioned "proper environment", will be added in subsequent
commits.)

Also, explicitly add the pkg-config paths to Bazel's search paths to
allow us to find dependencies built for wheels. This is required as we
cannot inject these into /usr/local on macOS, as we would in the Ubuntu
Docker containers.

tools/wheel/image/build-dependencies.sh

@@ -11,7 +11,4 @@ cmake -G Ninja \
 
 ninja
 
-ln -s /opt/drake-dependencies/lib/pkgconfig /usr/local/lib
-ln -s /opt/drake-dependencies/share/pkgconfig /usr/local/share
-
 ln -s /opt/drake-dependencies/bin/patchelf /usr/local/bin/patchelf

tools/workspace/boost/repository.bzl

@@ -35,7 +35,7 @@ def _impl(repository_ctx):
     os_result = determine_os(repository_ctx)
     if os_result.error != None:
         fail(os_result.error)
-    elif os_result.is_macos:
+    elif os_result.is_macos or os_result.is_macos_wheel:
         prefix = "{}/opt/boost".format(os_result.homebrew_prefix)
     elif os_result.is_ubuntu or os_result.is_manylinux:
         prefix = "/usr"

tools/workspace/double_conversion/repository.bzl

@@ -24,7 +24,7 @@ def _impl(repository_ctx):
             "/usr/include/double-conversion",
             "include/double-conversion",
         )
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         libdir = "/opt/drake-dependencies/lib"
         repository_ctx.symlink(
             "/opt/drake-dependencies/include/double-conversion",

tools/workspace/fmt/repository.bzl

@@ -17,7 +17,7 @@ def _impl(repo_ctx):
     if os_result.is_macos:
         # On macOS, we use fmt from homebrew via pkg-config.
         error = setup_pkg_config_repository(repo_ctx).error
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         # Compile from downloaded github sources.
         error = setup_github_repository(repo_ctx).error
     elif os_result.ubuntu_release == "20.04":

tools/workspace/gfortran/repository.bzl

@@ -30,15 +30,15 @@ def _gfortran_impl(repo_ctx):
     os_result = determine_os(repo_ctx)
     if os_result.error != None:
         fail(os_result.error)
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         suffix = ".dylib"
     else:
         suffix = ".so"
     libgfortran = "libgfortran{}".format(suffix)
     libgfortran_path = _find_library(repo_ctx, compiler, libgfortran)
 
     # The cc_library linking is different on Ubuntu vs macOS.
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         srcs = []
         linkopts = [
             "-L{}".format(repo_ctx.path(libgfortran_path).dirname),

tools/workspace/libjpeg/repository.bzl

@@ -16,7 +16,7 @@ def _impl(repository_ctx):
             "{}/opt/jpeg/include".format(os_result.homebrew_prefix),
             "include",
         )
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         libdir = "/opt/drake-dependencies/lib"
         for hdr in noarch_hdrs + ["jconfig.h"]:
             repository_ctx.symlink(

tools/workspace/nlopt/repository.bzl

@@ -8,7 +8,7 @@ def _impl(repository_ctx):
     if os_result.error != None:
         fail(os_result.error)
 
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         build_flavor = "macos"
         repository_ctx.symlink(
             "{}/opt/nlopt/include/nlopt.h".format(os_result.homebrew_prefix),

tools/workspace/openblas/repository.bzl

@@ -21,7 +21,7 @@ def _impl(repo_ctx):
     os_result = determine_os(repo_ctx)
     if os_result.error != None:
         fail(os_result.error)
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         error = setup_pkg_config_repository(repo_ctx).error
         if error != None:
             fail(error)

tools/workspace/opengl/repository.bzl

@@ -8,7 +8,7 @@ def _impl(repository_ctx):
     if os_result.error != None:
         fail(os_result.error)
 
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         repository_ctx.symlink(
             Label("@drake//tools/workspace/opengl:package-macos.BUILD.bazel"),
             "BUILD.bazel",

tools/workspace/os.bzl

@@ -4,15 +4,15 @@
 """A collection of OS-related utilities intended for use in repository rules,
 i.e., rules used by WORKSPACE files, not BUILD files.
 
-To opt-in to the "manylinux" build variant, set the environment variable
-`DRAKE_OS=manylinux` before running the build.  The most precise way to do
-this is to add a `user.bazelrc` file to the root of the Drake source tree
-with the following content:
+To opt-in to the "manylinux" or "macos_wheel" build variants, set the
+environment variable (e.g.) `DRAKE_OS=manylinux` before running the build.  The
+most precise way to do this is to add a `user.bazelrc` file to the root of the
+Drake source tree with the following content:
 
   common --repo_env=DRAKE_OS=manylinux
 
 Alternatively, you may pass `--repo_env=DRAKE_OS=manylinux` on the bazel
-command line.
+command line. (Replace "manylinux" with "macos_wheel" as appropriate.)
 """
 
 load("@drake//tools/workspace:execute.bzl", "which")
@@ -140,6 +140,19 @@ def _determine_macos(repository_ctx):
     # Shared error message text across different failure cases.
     error_prologue = "could not determine macOS version: "
 
+    # Allow the user to override the OS selection.
+    drake_os = repository_ctx.os.environ.get("DRAKE_OS", "")
+    is_macos_wheel = False
+    if len(drake_os) > 0:
+        if drake_os == "macos_wheel":
+            is_macos_wheel = True
+        else:
+            return _make_result(error = "{}{} DRAKE_OS={}".format(
+                error_prologue,
+                "unknown value for environment variable",
+                drake_os,
+            ))
+
     # Run sw_vers to determine macOS version.
     sw_vers = exec_using_which(repository_ctx, [
         "sw_vers",
@@ -166,6 +179,7 @@ def _determine_macos(repository_ctx):
         return _make_result(
             macos_release = macos_release,
             homebrew_prefix = homebrew_prefix,
+            is_wheel = is_macos_wheel,
         )
 
     # Nothing matched.
@@ -188,7 +202,8 @@ def determine_os(repository_ctx):
     libstdc++, etc.). In this case, the value of is_ubuntu will be False, but
     ubuntu_release will still be provided.
 
-    TODO(jwnimmer-tri) The is_macos_wheel option isn't detected / active yet.
+    The "macos_wheel" target indicates this build will be packaged into a
+    Python wheel.
 
     In case of an error, the "error" attribute of the struct will be set, and
     all of the other fields will be None or False.
@@ -211,8 +226,8 @@ def determine_os(repository_ctx):
         - macos_release: str like "11" or "12" (set any time the build platform
             is macOS, even for builds targeting "macos_wheel")
         - homebrew_prefix: str "/usr/local" or "/opt/homebrew" (set any time
-             the build platform is macOS, even for builds targeting
-             "macos_wheel")
+            the build platform is macOS, even for builds targeting
+            "macos_wheel")
     """
 
     os_name = repository_ctx.os.name

tools/workspace/pkg_config.bzl

@@ -52,18 +52,25 @@ def setup_pkg_config_repository(repository_ctx):
         [],
     ))
 
-    # Find the desired homebrew search path, if any.
-    homebrew_prefix = determine_os(repository_ctx).homebrew_prefix
-    homebrew_subdir = getattr(
-        repository_ctx.attr,
-        "homebrew_subdir",
-        "",
-    )
-    if homebrew_prefix and homebrew_subdir:
-        pkg_config_paths.insert(0, "{}/{}".format(
-            homebrew_prefix,
-            homebrew_subdir,
-        ))
+    os_result = determine_os(repository_ctx)
+
+    if os_result.is_macos or os_result.is_macos_wheel:
+        # Find the desired homebrew search path, if any.
+        homebrew_prefix = os_result.homebrew_prefix
+        homebrew_subdir = getattr(
+            repository_ctx.attr,
+            "homebrew_subdir",
+            "",
+        )
+        if homebrew_prefix and homebrew_subdir:
+            pkg_config_paths.insert(0, "{}/{}".format(
+                homebrew_prefix,
+                homebrew_subdir,
+            ))
+
+    if os_result.is_manylinux or os_result.is_macos_wheel:
+        pkg_config_paths.insert(0, "/opt/drake-dependencies/share/pkgconfig")
+        pkg_config_paths.insert(0, "/opt/drake-dependencies/lib/pkgconfig")
 
     # Check if we can find the required *.pc file of any version.
     result = _run_pkg_config(repository_ctx, args, pkg_config_paths)

tools/workspace/python/repository.bzl

@@ -50,6 +50,7 @@ load("@drake//tools/workspace:os.bzl", "determine_os")
 _VERSION_SUPPORT_MATRIX = {
     "ubuntu:20.04": ["3.8"],
     "macos": ["3.9"],
+    "macos_wheel": ["3.9"],
     "manylinux": ["3.8", "3.9"],
 }
 
@@ -69,7 +70,7 @@ def repository_python_info(repository_ctx):
         os_key += ":" + os_result.ubuntu_release
     versions_supported = _VERSION_SUPPORT_MATRIX[os_key]
 
-    if os_result.is_macos:
+    if os_result.is_macos or os_result.is_macos_wheel:
         # This value must match the interpreter_path in
         # @drake//tools/py_toolchain:macos_py3_runtime
         python = repository_ctx.attr.macos_interpreter_path

tools/workspace/snopt/repository.bzl

@@ -198,7 +198,7 @@ def _impl(repo_ctx):
             Label("@drake//tools/workspace/snopt:fortran-ubuntu.bzl"),
             "fortran.bzl",
         )
-    elif os_result.is_macos:
+    elif os_result.is_macos or os_result.is_macos_wheel:
         repo_ctx.symlink(
             Label("@drake//tools/workspace/snopt:fortran-macos.bzl"),
             "fortran.bzl",

tools/workspace/spdlog/repository.bzl

@@ -17,7 +17,7 @@ def _impl(repo_ctx):
     if os_result.is_macos:
         # On macOS, we use spdlog from homebrew via pkg-config.
         error = setup_pkg_config_repository(repo_ctx).error
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         # Compile it from downloaded github sources.
         error = setup_github_repository(repo_ctx).error
     else:

tools/workspace/suitesparse/repository.bzl

@@ -20,7 +20,7 @@ def _impl(repo_ctx):
         libdir = "{}/opt/suite-sparse/lib".format(
             os_result.homebrew_prefix,
         )
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         # TODO(jwnimmer-tri) Ideally, we wouldn't be hard-coding paths when
         # using manylinux.
         include = "/opt/drake-dependencies/include"

tools/workspace/vtk/repository.bzl

@@ -80,7 +80,7 @@ def _vtk_cc_library(
     elif os_result.is_ubuntu:
         if not header_only:
             srcs = ["lib/lib{}-{}.so.1".format(name, VTK_MAJOR_MINOR_VERSION)]
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         if not header_only:
             # TODO(jwnimmer-tri) Ideally, we wouldn't be hard-coding paths when
             # using manylinux.
@@ -136,7 +136,7 @@ def _impl(repository_ctx):
             sha256 = sha256,
             type = "tar.gz",
         )
-    elif os_result.is_manylinux:
+    elif os_result.is_manylinux or os_result.is_macos_wheel:
         repository_ctx.symlink("/opt/vtk/include", "include")
     else:
         fail("Operating system is NOT supported {}".format(os_result))
@@ -157,7 +157,7 @@ licenses([
     file_content += _vtk_cc_library(os_result, "vtkfmt")
 
     # NOTE: see /tools/wheel/image/vtk-args, this is to avoid packaging glew.
-    if os_result.is_manylinux:
+    if os_result.is_manylinux or os_result.is_macos_wheel:
         file_content += _vtk_cc_library(os_result, "vtkglew")
 
     file_content += _vtk_cc_library(os_result, "vtkkissfft")
@@ -835,15 +835,24 @@ licenses([
         "vtkGenericRenderWindowInteractor.h",
         "vtkRenderingUIModule.h",
     ]
-    if not os_result.is_macos:
+    if not os_result.is_macos and not os_result.is_macos_wheel:
         vtk_rendering_ui_hdrs.append("vtkXRenderWindowInteractor.h")
+
+    if os_result.is_macos_wheel:
+        # Normally this would be a private dependency, but no such thing when
+        # VTK is built static.
+        vtk_ui_linkopts = ["-framework Cocoa"]
+    else:
+        vtk_ui_linkopts = []
+
     file_content += _vtk_cc_library(
         os_result,
         "vtkRenderingUI",
         hdrs = vtk_rendering_ui_hdrs,
         deps = [
             ":vtkRenderingCore",
         ],
+        linkopts = vtk_ui_linkopts,
     )
 
     # Indirect dependency: omit headers.
@@ -869,12 +878,18 @@ licenses([
         "vtkShader.h",
         "vtkShaderProgram.h",
     ]
-    if not os_result.is_macos:
+    if not os_result.is_macos and not os_result.is_macos_wheel:
         vtk_rendering_opengl2_hdrs.append("vtkXOpenGLRenderWindow.h")
 
     if os_result.is_manylinux:
         vtk_glew_library = ":vtkglew"
+
+        # Normally these would be private dependencies, but no such thing when
+        # VTK is built static.
         vtk_opengl_linkopts = ["-lX11", "-lXt", "-lGLX"]
+    elif os_result.is_macos_wheel:
+        vtk_glew_library = ":vtkglew"
+        vtk_opengl_linkopts = []
     else:
         vtk_glew_library = "@glew"
         vtk_opengl_linkopts = []