different logic is required to access data in aspect

hasattr(ctx, "rule") to detect if we're running in an aspect doesn't
seem to work, so I had to explicitly pass a boolean into
construct_arguments()

Should fix clippy test in CI.

Author: dae

rust/private/clippy.bzl

@@ -92,6 +92,7 @@ def _clippy_aspect_impl(target, ctx):
         build_env_file = build_env_file,
         build_flags_files = build_flags_files,
         maker_path = clippy_marker.path,
+        aspect = True,
     )
 
     # Deny the default-on clippy warning levels.

rust/private/rustc.bzl

@@ -311,9 +311,12 @@ def get_linker_and_args(ctx, cc_toolchain, feature_configuration, rpaths):
 
     return ld, link_args, link_env
 
-def _expand_locations(ctx, env):
+def _expand_locations(ctx, env, aspect):
     "Expand $(location ...) references in user-provided env vars."
-    data = getattr(ctx.attr, "data", [])
+    if aspect:
+        data = getattr(ctx.rule.attr, "data", [])
+    else:
+        data = getattr(ctx.attr, "data", [])
     return dict([(k, ctx.expand_location(v, data)) for (k, v) in env.items()])
 
 def _process_build_scripts(
@@ -405,7 +408,8 @@ def construct_arguments(
         out_dir,
         build_env_file,
         build_flags_files,
-        maker_path = None):
+        maker_path = None,
+        aspect = False):
     """Builds an Args object containing common rustc flags
 
     Args:
@@ -545,7 +549,7 @@ def construct_arguments(
                 env["CARGO_BIN_EXE_" + dep_crate_info.output.basename] = dep_crate_info.output.short_path
 
     # Update environment with user provided variables.
-    env.update(_expand_locations(ctx, crate_info.rustc_env))
+    env.update(_expand_locations(ctx, crate_info.rustc_env, aspect))
 
     # This empty value satisfies Clippy, which otherwise complains about the
     # sysroot being undefined.