From 1ee423e0e68edad547d19779818ab24f1e802388 Mon Sep 17 00:00:00 2001
From: Daniel Wagner-Hall <dwagnerhall@apple.com>
Date: Mon, 20 Jun 2022 14:07:48 +0100
Subject: [PATCH] Re-add go_library non_go_transition

---
 go/private/rules/library.bzl    | 11 +++++++++
 go/private/rules/transition.bzl | 40 +++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/go/private/rules/library.bzl b/go/private/rules/library.bzl
index 4afb629c6e..1a0a55733c 100644
--- a/go/private/rules/library.bzl
+++ b/go/private/rules/library.bzl
@@ -31,6 +31,10 @@ load(
     "GoLibrary",
     "INFERRED_PATH",
 )
+load(
+    "//go/private/rules:transition.bzl",
+    "non_go_transition",
+)
 
 def _go_library_impl(ctx):
     """Implements the go_library() rule."""
@@ -59,6 +63,7 @@ go_library = rule(
     attrs = {
         "data": attr.label_list(
             allow_files = True,
+            cfg = non_go_transition,
             doc = """
             List of files needed by this rule at run-time.
             This may include data files needed or other programs that may be executed.
@@ -68,6 +73,7 @@ go_library = rule(
         ),
         "srcs": attr.label_list(
             allow_files = go_exts + asm_exts + cgo_exts,
+            cfg = non_go_transition,
             doc = """
             The list of Go source files that are compiled to create the package.
             Only `.go` and `.s` files are permitted, unless the `cgo` attribute is set,
@@ -110,6 +116,7 @@ go_library = rule(
         ),
         "embedsrcs": attr.label_list(
             allow_files = True,
+            cfg = non_go_transition,
             doc = """
             The list of files that may be embedded into the compiled package using `//go:embed`
             directives. All files must be in the same logical directory or a subdirectory as source files.
@@ -137,6 +144,7 @@ go_library = rule(
             """,
         ),
         "cdeps": attr.label_list(
+            cfg = non_go_transition,
             doc = """
             List of other libraries that the c code depends on.
             This can be anything that would be allowed in [cc_library deps] Only valid if `cgo = True`.
@@ -168,6 +176,9 @@ go_library = rule(
             """,
         ),
         "_go_context_data": attr.label(default = "//:go_context_data"),
+        "_allowlist_function_transition": attr.label(
+            default = "@bazel_tools//tools/allowlists/function_transition_allowlist",
+        ),
     },
     toolchains = [GO_TOOLCHAIN],
     doc = """This builds a Go library from a set of source files that are all part of
diff --git a/go/private/rules/transition.bzl b/go/private/rules/transition.bzl
index d08cb6f910..5d35163678 100644
--- a/go/private/rules/transition.bzl
+++ b/go/private/rules/transition.bzl
@@ -168,6 +168,46 @@ def _go_transition_impl(settings, attr):
 
     return settings
 
+def _non_go_transition_impl(settings, attr):
+    """Sets all Go settings to the values they had before the last go_transition.
+    non_go_transition sets all of the //go/config settings to the value they had
+    before the last go_transition. This should be used on all attributes of
+    go_library/go_binary/go_test that are built in the target configuration and
+    do not constitute advertise any Go providers.
+    Examples: This transition is applied to the 'data' attribute of go_binary so
+    that other Go binaries used at runtime aren't affected by a non-standard
+    link mode set on the go_binary target, but still use the same top-level
+    settings such as e.g. race instrumentation.
+    """
+    new_settings = {}
+    for key, original_key in _SETTING_KEY_TO_ORIGINAL_SETTING_KEY.items():
+        original_value = settings[original_key]
+        if original_value:
+            # Reset to the original value of the setting before go_transition.
+            new_settings[key] = json.decode(original_value)
+        else:
+            new_settings[key] = settings[key]
+
+        # Reset the value of the helper setting to its default for two reasons:
+        # 1. Performance: This ensures that the Go settings of non-Go
+        #    dependencies have the same values as before the go_transition,
+        #    which can prevent unnecessary rebuilds caused by configuration
+        #    changes.
+        # 2. Correctness in edge cases: If there is a path in the build graph
+        #    from a go_binary's non-Go dependency to a go_library that does not
+        #    pass through another go_binary (e.g., through a custom rule
+        #    replacement for go_binary), this transition could be applied again
+        #    and cause incorrect Go setting values.
+        new_settings[original_key] = ""
+
+    return new_settings
+
+non_go_transition = transition(
+    implementation = _non_go_transition_impl,
+    inputs = TRANSITIONED_GO_SETTING_KEYS + _SETTING_KEY_TO_ORIGINAL_SETTING_KEY.values(),
+    outputs = TRANSITIONED_GO_SETTING_KEYS + _SETTING_KEY_TO_ORIGINAL_SETTING_KEY.values(),
+)
+
 def _request_nogo_transition(settings, attr):
     """Indicates that we want the project configured nogo instead of a noop.