Refactor rustc_compile_action to construct CrateInfo internally (#2188)

In #2161, I anticipated to make
[create_crate_info_dict](https://github.com/bazelbuild/rules_rust/pull/2161/files#diff-b75adb75969318e09670c45b8eea5aaf147fdc1d2cf229a72a17bd39edf49163R853)
reusable across all rules and aspects.

The logic to construct `crate_info` is significantly different among the
rules and aspects. As I tried to to expand the arguments to make
`create_crate_info_dict` universally reusable, the arguments grow which
make it not worth anymore. This PR changes the refactoring approach.

Before (result from #2161)
```
def _rust_library_common()
    return rustc_compile_action(
        # the callback allows us to slowly refactor one rule or aspect at a time.
        create_crate_info_callback = create_crate_info_dict,
    )

def rustc_compile_action(create_crate_info_callback)
  if create_crate_info_callback:
    crate_info_dict = create_crate_info_callback()
```

After (result from this PR)
```
def _rust_library_common()
    # create crate_info_dict
    return rustc_compile_action(
        crate_info_dict = crate_info_dict,
    )

def rustc_compile_action(crate_info_dict)
  # crate_info_dict always exists
```

Instead of creating `crate_info_dict` at the beginning of
`rustc_compile_action`, this PR lifted the creation logic to the rules
and aspects completely so that they can add any custom logic without
caring about the `rustc_compile_action`'s implementation.

---------

Co-authored-by: scentini <rosica@google.com>

8 files changed, 63 insertions, 111 deletions

diff --git a/proto/prost/private/prost.bzl b/proto/prost/private/prost.bzl
index b513b154..1db20021 100644
--- a/proto/prost/private/prost.bzl
+++ b/proto/prost/private/prost.bzl
@@ -160,7 +160,7 @@ def _compile_rust(ctx, attr, crate_name, src, deps, edition):
         ctx = ctx,
         attr = attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = "rlib",
             root = src,
diff --git a/proto/protobuf/proto.bzl b/proto/protobuf/proto.bzl
index 2fcc1db5..6ff45cc2 100644
--- a/proto/protobuf/proto.bzl
+++ b/proto/protobuf/proto.bzl
@@ -20,7 +20,6 @@ load(
     _generate_proto = "rust_generate_proto",
     _generated_file_stem = "generated_file_stem",
 )
-load("//rust:defs.bzl", "rust_common")
 
 # buildifier: disable=bzl-visibility
 load("//rust/private:rustc.bzl", "rustc_compile_action")
@@ -214,7 +213,7 @@ def _rust_proto_compile(protos, descriptor_sets, imports, crate_name, ctx, is_gr
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = "rlib",
             root = lib_rs,
diff --git a/rust/private/rust.bzl b/rust/private/rust.bzl
index d736fc69..2914f4cc 100644
--- a/rust/private/rust.bzl
+++ b/rust/private/rust.bzl
@@ -14,15 +14,17 @@
 
 """Rust rule implementations"""
 
+load("@bazel_skylib//lib:paths.bzl", "paths")
 load("//rust/private:common.bzl", "rust_common")
 load("//rust/private:providers.bzl", "BuildInfo")
 load("//rust/private:rustc.bzl", "rustc_compile_action")
 load(
     "//rust/private:utils.bzl",
+    "can_build_metadata",
     "compute_crate_name",
     "crate_root_src",
-    "create_crate_info_dict",
     "dedent",
+    "determine_lib_name",
     "determine_output_hash",
     "expand_dict_value_locations",
     "find_toolchain",
@@ -31,6 +33,7 @@ load(
     "transform_deps",
     "transform_sources",
 )
+
 # TODO(marco): Separate each rule into its own file.
 
 def _assert_no_deprecated_attributes(_ctx):
@@ -140,10 +143,12 @@ def _rust_library_common(ctx, crate_type):
 
     toolchain = find_toolchain(ctx)
 
+    crate_name = compute_crate_name(ctx.workspace_name, ctx.label, toolchain, ctx.attr.crate_name)
+
     crate_root = getattr(ctx.file, "crate_root", None)
     if not crate_root:
         crate_root = crate_root_src(ctx.attr.name, ctx.files.srcs, crate_type)
-    _, crate_root = transform_sources(ctx, ctx.files.srcs, crate_root)
+    srcs, crate_root = transform_sources(ctx, ctx.files.srcs, crate_root)
 
     # Determine unique hash for this rlib.
     # Note that we don't include a hash for `cdylib` and `staticlib` since they are meant to be consumed externally
@@ -155,13 +160,48 @@ def _rust_library_common(ctx, crate_type):
     else:
         output_hash = determine_output_hash(crate_root, ctx.label)
 
+    rust_lib_name = determine_lib_name(
+        crate_name,
+        crate_type,
+        toolchain,
+        output_hash,
+    )
+    rust_lib = ctx.actions.declare_file(rust_lib_name)
+    rust_metadata = None
+    if can_build_metadata(toolchain, ctx, crate_type) and not ctx.attr.disable_pipelining:
+        rust_metadata = ctx.actions.declare_file(
+            paths.replace_extension(rust_lib_name, ".rmeta"),
+            sibling = rust_lib,
+        )
+
+    deps = transform_deps(ctx.attr.deps)
+    proc_macro_deps = transform_deps(ctx.attr.proc_macro_deps + get_import_macro_deps(ctx))
+
     return rustc_compile_action(
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
         output_hash = output_hash,
-        crate_type = crate_type,
-        create_crate_info_callback = create_crate_info_dict,
+        crate_info_dict = dict(
+            name = crate_name,
+            type = crate_type,
+            root = crate_root,
+            srcs = depset(srcs),
+            deps = depset(deps),
+            proc_macro_deps = depset(proc_macro_deps),
+            aliases = ctx.attr.aliases,
+            output = rust_lib,
+            metadata = rust_metadata,
+            edition = get_edition(ctx.attr, toolchain, ctx.label),
+            rustc_env = ctx.attr.rustc_env,
+            rustc_env_files = ctx.files.rustc_env_files,
+            is_test = False,
+            data = depset(ctx.files.data),
+            compile_data = depset(ctx.files.compile_data),
+            compile_data_targets = depset(ctx.attr.compile_data),
+            owner = ctx.label,
+            _rustc_env_attr = ctx.attr.rustc_env,
+        ),
     )
 
 def _rust_binary_impl(ctx):
@@ -191,7 +231,7 @@ def _rust_binary_impl(ctx):
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = ctx.attr.crate_type,
             root = crate_root,
@@ -266,7 +306,7 @@ def _rust_test_impl(ctx):
         ))
 
         # Build the test binary using the dependency's srcs.
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate.name,
             type = crate_type,
             root = crate.root,
@@ -310,7 +350,7 @@ def _rust_test_impl(ctx):
         )
 
         # Target is a standalone crate. Build the test binary as its own crate.
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = compute_crate_name(ctx.workspace_name, ctx.label, toolchain, ctx.attr.crate_name),
             type = crate_type,
             root = crate_root,
@@ -333,7 +373,7 @@ def _rust_test_impl(ctx):
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = crate_info,
+        crate_info_dict = crate_info_dict,
         rust_flags = ["--test"] if ctx.attr.use_libtest_harness else ["--cfg", "test"],
         skip_expanding_rustc_env = True,
     )
diff --git a/rust/private/rustc.bzl b/rust/private/rustc.bzl
index 6ae6f30c..c972e478 100644
--- a/rust/private/rustc.bzl
+++ b/rust/private/rustc.bzl
@@ -1085,13 +1085,9 @@ def rustc_compile_action(
         attr,
         toolchain,
         rust_flags = [],
-        crate_type = None,
-        crate_info = None,
         output_hash = None,
         force_all_deps_direct = False,
-        # TODO: Remove create_crate_info_callback and skip_expanding_rustc_env attributes
-        # after all CrateInfo structs are constructed in rustc_compile_action
-        create_crate_info_callback = None,
+        crate_info_dict = None,
         skip_expanding_rustc_env = False):
     """Create and run a rustc compile action based on the current rule's attributes
 
@@ -1099,13 +1095,11 @@ def rustc_compile_action(
         ctx (ctx): The rule's context object
         attr (struct): Attributes to use for the rust compile action
         toolchain (rust_toolchain): The current `rust_toolchain`
-        crate_type: TODO
-        crate_info (CrateInfo): The CrateInfo provider for the current target.
         output_hash (str, optional): The hashed path of the crate root. Defaults to None.
         rust_flags (list, optional): Additional flags to pass to rustc. Defaults to [].
         force_all_deps_direct (bool, optional): Whether to pass the transitive rlibs with --extern
             to the commandline as opposed to -L.
-        create_crate_info_callback: A callback to construct a mutable dict for constructor CrateInfo
+        crate_info_dict: A mutable dict used to create CrateInfo provider
         skip_expanding_rustc_env (bool, optional): Whether to expand CrateInfo.rustc_env
 
     Returns:
@@ -1114,19 +1108,11 @@ def rustc_compile_action(
             - (DepInfo): The transitive dependencies of this crate.
             - (DefaultInfo): The output file for this crate, and its runfiles.
     """
-    # TODO: Remove create_crate_info_callback after all rustc_compile_action callers migrate to
-    # removing CrateInfo construction before `rust_compile_action
+    crate_info = rust_common.create_crate_info(**crate_info_dict)
 
-    crate_info_dict = None
-    if create_crate_info_callback != None:
-        if ctx == None or toolchain == None or crate_type == None or crate_info != None:
-            fail("FAIL", ctx, toolchain, crate_type)
-        crate_info_dict = create_crate_info_callback(ctx, toolchain, crate_type)
-
-    if crate_info_dict != None:
-        crate_info = rust_common.create_crate_info(**crate_info_dict)
-
-    build_metadata = getattr(crate_info, "metadata", None)
+    build_metadata = None
+    if "metadata" in crate_info_dict:
+        build_metadata = crate_info_dict["metadata"]
 
     cc_toolchain, feature_configuration = find_cc_toolchain(ctx)
 
@@ -1144,9 +1130,9 @@ def rustc_compile_action(
             experimental_use_cc_common_link = toolchain._experimental_use_cc_common_link
 
     dep_info, build_info, linkstamps = collect_deps(
-        deps = crate_info.deps,
-        proc_macro_deps = crate_info.proc_macro_deps,
-        aliases = crate_info.aliases,
+        deps = crate_info_dict["deps"],
+        proc_macro_deps = crate_info_dict["proc_macro_deps"],
+        aliases = crate_info_dict["aliases"],
         are_linkstamps_supported = _are_linkstamps_supported(
             feature_configuration = feature_configuration,
             has_grep_includes = hasattr(ctx.attr, "_use_grep_includes"),
diff --git a/rust/private/utils.bzl b/rust/private/utils.bzl
index ddee229b..7b0fe23e 100644
--- a/rust/private/utils.bzl
+++ b/rust/private/utils.bzl
@@ -727,7 +727,7 @@ def _shortest_src_with_basename(srcs, basename):
                 shortest = f
     return shortest
 
-def _determine_lib_name(name, crate_type, toolchain, lib_hash = None):
+def determine_lib_name(name, crate_type, toolchain, lib_hash = None):
     """See https://github.com/bazelbuild/rules_rust/issues/405
 
     Args:
@@ -849,68 +849,3 @@ def _symlink_for_non_generated_source(ctx, src_file, package_root):
         return src_symlink
     else:
         return src_file
-
-def create_crate_info_dict(ctx, toolchain, crate_type):
-    """Creates a mutable dict() representing CrateInfo provider
-
-    create_crate_info_dict is a *temporary* solution until create_crate_info is completely moved into
-    rustc_compile_action function.
-
-    The function is currently used as a callback to support constructing CrateInfo in rustc_compile_action
-    to ensure `CrateInfo.rustc_env` is fully loaded with all the env vars passed to rustc.
-
-    Args:
-        ctx (struct): The current rule's context
-        toolchain (toolchain): The rust toolchain
-        crate_type (String): one of lib|rlib|dylib|staticlib|cdylib|proc-macro
-
-    Returns:
-        File: The created symlink if a non-generated file, or the file itself.
-    """
-    crate_name = compute_crate_name(ctx.workspace_name, ctx.label, toolchain, ctx.attr.crate_name)
-    crate_root = getattr(ctx.file, "crate_root", None)
-    if not crate_root:
-        crate_root = crate_root_src(ctx.attr.name, ctx.files.srcs, crate_type)
-    srcs, crate_root = transform_sources(ctx, ctx.files.srcs, crate_root)
-
-    if crate_type in ["cdylib", "staticlib"]:
-        output_hash = None
-    else:
-        output_hash = determine_output_hash(crate_root, ctx.label)
-
-    deps = transform_deps(ctx.attr.deps)
-    proc_macro_deps = transform_deps(ctx.attr.proc_macro_deps + get_import_macro_deps(ctx))
-    rust_lib_name = _determine_lib_name(
-        crate_name,
-        crate_type,
-        toolchain,
-        output_hash,
-    )
-    rust_lib = ctx.actions.declare_file(rust_lib_name)
-    rust_metadata = None
-    if can_build_metadata(toolchain, ctx, crate_type) and not ctx.attr.disable_pipelining:
-        rust_metadata = ctx.actions.declare_file(
-            paths.replace_extension(rust_lib_name, ".rmeta"),
-            sibling = rust_lib,
-        )
-
-    return dict(
-        name = crate_name,
-        type = crate_type,
-        root = crate_root,
-        srcs = depset(srcs),
-        deps = depset(deps),
-        proc_macro_deps = depset(proc_macro_deps),
-        aliases = ctx.attr.aliases,
-        output = rust_lib,
-        metadata = rust_metadata,
-        edition = get_edition(ctx.attr, toolchain, ctx.label),
-        rustc_env = ctx.attr.rustc_env,
-        rustc_env_files = ctx.files.rustc_env_files,
-        is_test = False,
-        data = depset(ctx.files.data),
-        compile_data = depset(ctx.files.compile_data),
-        compile_data_targets = depset(ctx.attr.compile_data),
-        owner = ctx.label,
-        _rustc_env_attr = ctx.attr.rustc_env,
-    )
diff --git a/test/unit/consistent_crate_name/with_modified_crate_name.bzl b/test/unit/consistent_crate_name/with_modified_crate_name.bzl
index 335ec128..7a3bca60 100644
--- a/test/unit/consistent_crate_name/with_modified_crate_name.bzl
+++ b/test/unit/consistent_crate_name/with_modified_crate_name.bzl
@@ -1,7 +1,5 @@
 """A custom rule that threats all its dependencies as direct dependencies."""
 
-load("//rust:defs.bzl", "rust_common")
-
 # buildifier: disable=bzl-visibility
 load("//rust/private:providers.bzl", "BuildInfo", "CrateInfo", "DepInfo", "DepVariantInfo")
 
@@ -35,7 +33,7 @@ def _with_modified_crate_name_impl(ctx):
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = crate_type,
             root = crate_root,
diff --git a/test/unit/force_all_deps_direct/generator.bzl b/test/unit/force_all_deps_direct/generator.bzl
index f56d09c2..959687c6 100644
--- a/test/unit/force_all_deps_direct/generator.bzl
+++ b/test/unit/force_all_deps_direct/generator.bzl
@@ -1,9 +1,6 @@
 """A custom rule that threats all its dependencies as direct dependencies."""
 
 # buildifier: disable=bzl-visibility
-load("//rust/private:common.bzl", "rust_common")
-
-# buildifier: disable=bzl-visibility
 load("//rust/private:providers.bzl", "BuildInfo", "CrateInfo", "DepInfo", "DepVariantInfo")
 
 # buildifier: disable=bzl-visibility
@@ -52,7 +49,7 @@ EOF
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = crate_type,
             root = rs_file,
diff --git a/test/unit/pipelined_compilation/wrap.bzl b/test/unit/pipelined_compilation/wrap.bzl
index b00f761a..7ceef1c0 100644
--- a/test/unit/pipelined_compilation/wrap.bzl
+++ b/test/unit/pipelined_compilation/wrap.bzl
@@ -1,9 +1,6 @@
 """A custom rule that wraps a crate called to_wrap."""
 
 # buildifier: disable=bzl-visibility
-load("//rust/private:common.bzl", "rust_common")
-
-# buildifier: disable=bzl-visibility
 load("//rust/private:providers.bzl", "BuildInfo", "CrateInfo", "DepInfo", "DepVariantInfo")
 
 # buildifier: disable=bzl-visibility
@@ -61,7 +58,7 @@ EOF
         ctx = ctx,
         attr = ctx.attr,
         toolchain = toolchain,
-        crate_info = rust_common.create_crate_info(
+        crate_info_dict = dict(
             name = crate_name,
             type = crate_type,
             root = rs_file,