Migrate to the modern linker input API. (#463)

See bazelbuild/bazel#10860.

Author: benjaminp

bindgen/bindgen.bzl

@@ -13,8 +13,7 @@
 # limitations under the License.
 
 # buildifier: disable=module-docstring
-load("@io_bazel_rules_rust//rust:private/legacy_cc_starlark_api_shim.bzl", "get_libs_for_static_executable")
-load("@io_bazel_rules_rust//rust:private/utils.bzl", "find_toolchain")
+load("@io_bazel_rules_rust//rust:private/utils.bzl", "find_toolchain", "get_libs_for_static_executable")
 load("@io_bazel_rules_rust//rust:rust.bzl", "rust_library")
 
 def rust_bindgen_library(

docs/index.md

@@ -36,7 +36,7 @@ load("@io_bazel_rules_rust//:workspace.bzl", "rust_workspace")
 rust_workspace()
 ```
 
-The rules are under active development, as such the lastest commit on the master branch should be used. `master` currently requires Bazel >= 0.26.0.
+The rules are under active development, as such the lastest commit on the master branch should be used. `master` currently requires Bazel >= 3.0.0.
 
 ## Rules
 

rust/private/legacy_cc_starlark_api_shim.bzl

@@ -21,8 +21,7 @@ load(
 )
 load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
 load("@io_bazel_rules_rust_bazel_version//:def.bzl", "BAZEL_VERSION")
-load("@io_bazel_rules_rust//rust:private/legacy_cc_starlark_api_shim.bzl", "get_libs_for_static_executable")
-load("@io_bazel_rules_rust//rust:private/utils.bzl", "get_lib_name", "relativize")
+load("@io_bazel_rules_rust//rust:private/utils.bzl", "get_lib_name", "get_libs_for_static_executable", "relativize")
 
 CrateInfo = provider(
     doc = "A provider containing general Crate information.",

rust/private/rustc.bzl

@@ -94,3 +94,32 @@ def determine_output_hash(crate_root):
         str: A string representation of the hash.
     """
     return repr(hash(crate_root.path))
+
+def get_libs_for_static_executable(dep):
+    """find the libraries used for linking a static executable.
+
+    Args:
+        dep (Target): A cc_library target.
+
+    Returns:
+        depset: A depset[File]
+    """
+    linker_inputs = dep[CcInfo].linking_context.linker_inputs.to_list()
+    return depset([_get_preferred_artifact(lib) for li in linker_inputs for lib in li.libraries])
+
+def _get_preferred_artifact(library_to_link):
+    """Get the first available library to link from a LibraryToLink object.
+
+    Args:
+        library_to_link (LibraryToLink): See the followg links for additional details:
+          https://docs.bazel.build/versions/master/skylark/lib/LibraryToLink.html
+
+    Returns:
+        File: Returns the first valid library type (only one is expected)
+    """
+    return (
+        library_to_link.static_library or
+        library_to_link.pic_static_library or
+        library_to_link.interface_library or
+        library_to_link.dynamic_library
+    )

rust/private/utils.bzl

@@ -2,7 +2,7 @@
 load("@bazel_skylib//:workspace.bzl", "bazel_skylib_workspace")
 load("@bazel_skylib//lib:versions.bzl", "versions")
 
-_MINIMUM_SUPPORTED_BAZEL_VERSION = "0.17.1"
+_MINIMUM_SUPPORTED_BAZEL_VERSION = "3.0.0"
 
 def _bazel_version_impl(repository_ctx):
     """The implementation for the `bazel_version` rule