[py] generate the internal BiDi protocol layer from the shared binding-neutral schema

.gitignore

@@ -68,6 +68,12 @@ __pycache__
 *.pyc
 dist/
 py/selenium/webdriver/common/bidi/
+# Generated internal BiDi protocol modules; the hand-written runtime beside them stays tracked.
+py/selenium/webdriver/common/_bidi/*
+!py/selenium/webdriver/common/_bidi/__init__.py
+!py/selenium/webdriver/common/_bidi/serialization.py
+!py/selenium/webdriver/common/_bidi/transport.py
+!py/selenium/webdriver/common/_bidi/domain.py
 py/selenium/webdriver/common/devtools/**/*
 !py/selenium/webdriver/common/devtools/util.py
 py/selenium/webdriver/common/linux/

py/BUILD.bazel

@@ -11,6 +11,7 @@ load("//common:defs.bzl", "copy_file")
 load("//py:defs.bzl", "generate_devtools", "generate_devtools_latest", "py_test_suite")
 load("//py/private:browsers.bzl", "BROWSERS")
 load("//py/private:generate_bidi.bzl", "generate_bidi")
+load("//py/private:generate_bidi_protocol.bzl", "generate_bidi_protocol")
 load("//py/private:import.bzl", "py_import")
 load("//py/private:sphinx_docs.bzl", "sphinx_docs")
 
@@ -310,6 +311,7 @@ py_library(
             "selenium/webdriver/common/actions/**",
             "selenium/webdriver/common/alert.py",
             "selenium/webdriver/common/api_request_context.py",
+            "selenium/webdriver/common/_bidi/**",
             "selenium/webdriver/common/bidi/**",
             "selenium/webdriver/common/devtools/**",
             "selenium/webdriver/common/fedcm/**",
@@ -546,6 +548,7 @@ py_library(
     visibility = ["//visibility:public"],
     deps = [
         ":bidi",
+        ":bidi_protocol",
         ":chrome",
         ":chromium",
         ":common",
@@ -578,6 +581,7 @@ py_package(
         "py.selenium.webdriver.chrome",
         "py.selenium.webdriver.chromium",
         "py.selenium.webdriver.common",
+        "py.selenium.webdriver.common._bidi",
         "py.selenium.webdriver.common.bidi",
         "py.selenium.webdriver.common.devtools",
         "py.selenium.webdriver.common.devtools.latest",
@@ -772,6 +776,51 @@ generate_bidi(
     spec_version = "1.0",
 )
 
+# Schema-driven internal BiDi protocol layer: generated at build time from the
+# shared BiDi schema into `selenium/webdriver/common/_bidi/`. Only the hand-written
+# runtime (serialization/transport/domain) is checked in; the domain modules are
+# generated by the rule below and never committed.
+generate_bidi_protocol(
+    name = "create-bidi-protocol-src",
+    generator = ":generate-bidi-protocol-tool",
+    package = "selenium/webdriver/common/_bidi",
+    schema = "//javascript/selenium-webdriver:create-bidi-src_schema",
+)
+
+# Build-graph tool: the generator invoked by the rule above (schema + output dir
+# passed as arguments). No baked args, so it is reusable in the exec configuration.
+py_binary(
+    name = "generate-bidi-protocol-tool",
+    srcs = ["generate_bidi_protocol.py"],
+    main = "generate_bidi_protocol.py",
+    visibility = ["//visibility:private"],
+)
+
+# `bazel run //py:generate-bidi-protocol` regenerates the checked-out tree for local
+# development (writes under BUILD_WORKSPACE_DIRECTORY); the build itself uses the rule.
+py_binary(
+    name = "generate-bidi-protocol",
+    srcs = ["generate_bidi_protocol.py"],
+    args = ["$(location //javascript/selenium-webdriver:create-bidi-src_schema)"],
+    data = ["//javascript/selenium-webdriver:create-bidi-src_schema"],
+    main = "generate_bidi_protocol.py",
+    visibility = ["//visibility:public"],
+)
+
+py_library(
+    name = "bidi_protocol",
+    # Listed explicitly, not globbed: a local generate run drops the generated modules here too, and a glob would double them against the rule's outputs.
+    srcs = [":create-bidi-protocol-src"] + [
+        "selenium/webdriver/common/_bidi/__init__.py",
+        "selenium/webdriver/common/_bidi/domain.py",
+        "selenium/webdriver/common/_bidi/serialization.py",
+        "selenium/webdriver/common/_bidi/transport.py",
+    ],
+    imports = ["."],
+    visibility = ["//visibility:public"],
+    deps = [":exceptions"],
+)
+
 py_test_suite(
     name = "unit",
     size = "small",
@@ -800,7 +849,10 @@ py_library(
     deps = [],
 )
 
-BIDI_TESTS = glob(["test/selenium/webdriver/common/**/*bidi*_tests.py"])
+BIDI_TESTS = glob([
+    "test/selenium/webdriver/common/bidi/**/*_tests.py",
+    "test/selenium/webdriver/common/_bidi/**/*_tests.py",
+])
 
 # Tests that have bidi and classic implementations.
 BIDI_IMPLEMENTATIONS = []
@@ -1056,7 +1108,8 @@ FEATURE_SUITE_DEFS = {
         target_compatible_with = BROWSERS[browser]["target_compatible_with"],
         test_suffix = "%s-bidi" % browser,
         deps = [
-            ":common_alert",  # bidi_browsing_context_tests.py calls EC.alert_is_present()
+            ":bidi_protocol",  # bidi/protocol_tests.py imports the generated _bidi layer directly
+            ":common_alert",  # bidi/browsing_context_tests.py calls EC.alert_is_present()
             ":init-tree",
             ":webserver",
         ] + BROWSER_TESTS[browser]["deps"] + TEST_DEPS,

py/TESTING.md

@@ -53,7 +53,7 @@ bazel test //py/... --test_output=streamed  # Live output for debugging
 bazel test //py:test-chrome --headless
 
 # Run a specific test in a test file
-bazel test //py:test/selenium/webdriver/common/bidi_browsing_context_tests-chrome-bidi \
+bazel test //py:test/selenium/webdriver/common/bidi/browsing_context_tests-chrome-bidi \
   --test_arg=-k \
   --test_arg=test_get_tree_with_child \