Add data to py_venv rule (#534)

If your venv requires runtime dependencies in the build, these
previously weren't built

---------

Co-authored-by: Alex Eagle <[email protected]>

Author: keith

docs/venv.md

@@ -59,7 +59,7 @@ py_image_layer = _py_image_layer
 
 resolutions = _resolutions
 
-def _py_binary_or_test(name, rule, srcs, main, deps = [], resolutions = {}, **kwargs):
+def _py_binary_or_test(name, rule, srcs, main, data = [], deps = [], resolutions = {}, **kwargs):
     # Compatibility with rules_python, see docs in py_executable.bzl
     main_target = "{}.find_main".format(name)
     determine_main(
@@ -76,6 +76,7 @@ def _py_binary_or_test(name, rule, srcs, main, deps = [], resolutions = {}, **kw
         name = name,
         srcs = srcs,
         main = main_target,
+        data = data,
         deps = deps,
         resolutions = resolutions,
         package_collisions = package_collisions,
@@ -84,6 +85,7 @@ def _py_binary_or_test(name, rule, srcs, main, deps = [], resolutions = {}, **kw
 
     _py_venv(
         name = "{}.venv".format(name),
+        data = data,
         deps = deps,
         imports = kwargs.get("imports"),
         resolutions = resolutions,

py/defs.bzl

@@ -98,6 +98,15 @@ py_venv_rule = rule(
             allow_files = True,
             providers = [[PyInfo], [PyVirtualInfo]],
         ),
+        "data": attr.label_list(
+            doc = """Runtime dependencies of the program.
+
+        The transitive closure of the `data` dependencies will be available in the `.runfiles`
+        folder for this binary/test. The program may optionally use the Runfiles lookup library to
+        locate the data files, see https://pypi.org/project/bazel-runfiles/.
+        """,
+            allow_files = True,
+        ),
         "imports": attr.string_list(
             doc = "List of import directories to be added to the PYTHONPATH.",
             default = [],