use flags-as-proto to determine command line schema

MODULE.bazel

@@ -270,6 +270,7 @@ go_deps.gazelle_override(
     ],
     path = "cel.dev/expr",
 )
+
 use_repo(
     go_deps,
     "co_honnef_go_tools",

WORKSPACE.bzlmod

@@ -196,6 +196,26 @@ load("@io_bazel_rules_webtesting//web:go_repositories.bzl", web_test_go_reposito
 
 web_test_go_repositories()
 
+load("@bazel_gazelle//:deps.bzl", "go_repository", "gazelle_dependencies")
+
+go_repository(
+    name = "com_github_bazelbuild_bazel",
+    build_file_generation = "clean",
+    build_file_proto_mode = "package",
+    importpath = "github.com/bazelbuild/bazel",
+    tag = "7.4.1",
+    repo_mapping = {
+        "@rules_go": "@io_bazel_rules_go",
+    },
+)
+
+gazelle_dependencies(
+    go_env = {
+        "GOPROXY": "https://proxy.golang.org|direct",
+    },
+    go_sdk = "rules_go~~go_sdk~buildbuddy__download_0",
+)
+
 register_toolchains(
     "@buildbuddy_toolchain//:ubuntu_cc_toolchain",
 )

cli/parser/BUILD

@@ -14,7 +14,7 @@ go_library(
         "//server/remote_cache/digest",
         "//server/util/disk",
         "//server/util/proto",
-        "@com_github_bazelbuild_bazel_protos//",
+        "@com_github_bazelbuild_bazel//src/main/protobuf:bazel_flags_go_proto",
         "@com_github_google_shlex//:shlex",
     ],
 )

cli/parser/parser.go

@@ -365,15 +365,66 @@ func (s *CommandLineSchema) CommandSupportsOpt(opt string) bool {
 	return false
 }
 
+func GetOptionSetsfromProto(args []string, flagCollection *bfpb.FlagCollection, onlyStartupOptions bool) (map[string]*OptionSet, error) {
+	sets := make(map[string]*OptionSet)
+	for _, info := range flagCollection.FlagInfos {
+		o := &Option{
+			Name: info.GetName(),
+			ShortName: info.GetAbbreviation(),
+			Multi: info.GetAllowsMultiple(),
+			BoolLike: info.GetHasNegativeFlag(),
+		}
+		for _, cmd := range info.GetCommands() {
+			var set *OptionSet
+			var ok bool
+			if set, ok = sets[cmd]; !ok {
+				set = &OptionSet{
+					All: []*Option{},
+					ByName: make(map[string]*Option),
+					ByShortName: make(map[string]*Option),
+				}
+				sets[cmd] = set
+			}
+			set.All = append(set.All, o)
+			set.ByName[o.Name] = o
+			if o.ShortName != "" {
+				set.ByShortName[o.ShortName] = o
+			}
+		}
+	}
+	return sets, nil
+}
+
 // GetCommandLineSchema returns the effective CommandLineSchemas for the given
 // command line.
 func getCommandLineSchema(args []string, bazelHelp BazelHelpFunc, onlyStartupOptions bool) (*CommandLineSchema, error) {
-	startupHelp, err := bazelHelp("startup_options")
-	if err != nil {
-		return nil, err
+	var optionSets map[string]*OptionSet
+	// try flags-as-proto first; fall back to parsing help if bazel version does not support it.
+	if protoHelp, err := bazelHelp("flags-as-proto"); err == nil {
+		protoHelp = strings.TrimSpace(protoHelp)
+		b, err := base64.StdEncoding.DecodeString(protoHelp)
+		if err != nil {
+			return nil, err
+		}
+		flagCollection := &bfpb.FlagCollection{}
+		if err := proto.Unmarshal(b, flagCollection); err != nil {
+			return nil, err
+		}
+		sets, err := GetOptionSetsfromProto(args, flagCollection, onlyStartupOptions)
+		if err != nil {
+			return nil, err
+		}
+		optionSets = sets
 	}
-	schema := &CommandLineSchema{
-		StartupOptions: parseBazelHelp(startupHelp, "startup_options"),
+	schema := &CommandLineSchema{}
+	if startupOptions, ok := optionSets["startup"]; ok {
+		schema.StartupOptions = startupOptions
+	} else {
+		startupHelp, err := bazelHelp("startup_options")
+		if err != nil {
+			return nil, err
+		}
+		schema.StartupOptions = parseBazelHelp(startupHelp, "startup_options")
 	}
 	bazelCommands, err := BazelCommands()
 	if err != nil {
@@ -409,11 +460,15 @@ func getCommandLineSchema(args []string, bazelHelp BazelHelpFunc, onlyStartupOpt
 	if schema.Command == "" {
 		return schema, nil
 	}
-	commandHelp, err := bazelHelp(schema.Command)
-	if err != nil {
-		return nil, err
+	if commandOptions, ok := optionSets[schema.Command]; ok {
+		schema.CommandOptions = commandOptions
+	} else {
+		commandHelp, err := bazelHelp(schema.Command)
+		if err != nil {
+			return nil, err
+		}
+		schema.CommandOptions = parseBazelHelp(commandHelp, schema.Command)
 	}
-	schema.CommandOptions = parseBazelHelp(commandHelp, schema.Command)
 	return schema, nil
 }
 

deps.bzl

@@ -429,11 +429,14 @@ def install_go_mod_dependencies(workspace_name = "buildbuddy"):
 
     # keep
     go_repository(
-        name = "com_github_bazelbuild_bazel_protos",
-        build_file_generation = "on",
+        name = "com_github_bazelbuild_bazel",
+        build_file_generation = "clean",
         build_file_proto_mode = "package",
-        importpath = "github.com/bazelbuild/bazel/src/main/protobuf",
+        importpath = "github.com/bazelbuild/bazel",
         tag = "7.4.1",
+        repo_mapping = {
+            "@rules_go": "@io_bazel_rules_go",
+        },
     )
     go_repository(
         name = "com_github_bazelbuild_bazel_gazelle",