Merge pull request #153 from google/antlr

antlr: drop rules_antlr for custom rules

Author: TristonianJones

bazel/BUILD

@@ -1 +1,9 @@
 package(default_visibility = ["//visibility:public"])
+
+load("@rules_java//java:defs.bzl", "java_binary")
+
+java_binary(
+    name = "antlr4_tool",
+    runtime_deps = ["@antlr4_jar//jar"],
+    main_class = "org.antlr.v4.Tool",
+)

bazel/antlr.bzl

@@ -16,25 +16,18 @@
 Generate C++ parser and lexer from a grammar file.
 """
 
-load("@rules_antlr//antlr:antlr4.bzl", "antlr")
-
-def antlr_cc_library(name, src, package = None, listener = False, visitor = True):
+def antlr_cc_library(name, src, package):
     """Creates a C++ lexer and parser from a source grammar.
 
     Args:
       name: Base name for the lexer and the parser rules.
       src: source ANTLR grammar file
       package: The namespace for the generated code
-      listener: generate ANTLR listener (default: False)
-      visitor: generate ANTLR visitor (default: True)
     """
     generated = name + "_grammar"
-    antlr(
+    antlr_library(
         name = generated,
-        srcs = [src],
-        language = "Cpp",
-        listener = listener,
-        visitor = visitor,
+        src = src,
         package = package,
     )
     native.cc_library(
@@ -46,3 +39,63 @@ def antlr_cc_library(name, src, package = None, listener = False, visitor = True
         ],
         linkstatic = 1,
     )
+
+def _antlr_library(ctx):
+    output = ctx.actions.declare_directory(ctx.attr.name)
+
+    antlr_args = ctx.actions.args()
+    antlr_args.add("-Dlanguage=Cpp")
+    antlr_args.add("-no-listener")
+    antlr_args.add("-visitor")
+    antlr_args.add("-o", output.path)
+    antlr_args.add("-package", ctx.attr.package)
+    antlr_args.add(ctx.file.src)
+
+    basename = ctx.file.src.basename[:-3]
+    suffixes = ["Lexer", "Parser", "BaseVisitor", "Visitor"]
+
+    ctx.actions.run(
+        arguments = [antlr_args],
+        inputs = [ctx.file.src],
+        outputs = [output],
+        executable = ctx.executable._tool,
+        progress_message = "Processing ANTLR grammar",
+    )
+
+    files = []
+    for suffix in suffixes:
+        header = ctx.actions.declare_file(basename + suffix + ".h")
+        source = ctx.actions.declare_file(basename + suffix + ".cpp")
+        generated = output.path + "/" + ctx.file.src.short_path[:-3] + suffix
+
+        ctx.actions.run_shell(
+            mnemonic = "CopyHeader" + suffix,
+            inputs = [output],
+            outputs = [header],
+            command = 'cp "{generated}" "{out}"'.format(generated = generated + ".h", out = header.path),
+        )
+        ctx.actions.run_shell(
+            mnemonic = "CopySource" + suffix,
+            inputs = [output],
+            outputs = [source],
+            command = 'cp "{generated}" "{out}"'.format(generated = generated + ".cpp", out = source.path),
+        )
+
+        files.append(header)
+        files.append(source)
+
+    compilation_context = cc_common.create_compilation_context(headers = depset(files))
+    return [DefaultInfo(files = depset(files)), CcInfo(compilation_context = compilation_context)]
+
+antlr_library = rule(
+    implementation = _antlr_library,
+    attrs = {
+        "src": attr.label(allow_single_file = [".g4"], mandatory = True),
+        "package": attr.string(),
+        "_tool": attr.label(
+            executable = True,
+            cfg = "host",
+            default = Label("//bazel:antlr4_tool"),
+        ),
+    },
+)

bazel/deps.bzl

@@ -2,7 +2,7 @@
 Main dependencies of cel-cpp.
 """
 
-load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive", "http_jar")
 
 def base_deps():
     """Base evaluator and test dependencies."""
@@ -69,15 +69,9 @@ def base_deps():
 
 def parser_deps():
     """ANTLR dependency for the parser."""
-    http_archive(
-        name = "rules_antlr",
-        sha256 = "26e6a83c665cf6c1093b628b3a749071322f0f70305d12ede30909695ed85591",
-        strip_prefix = "rules_antlr-0.5.0",
-        urls = ["https://github.com/marcohu/rules_antlr/archive/0.5.0.tar.gz"],
-    )
+    # Apr 15, 2022
+    ANTLR4_VERSION = "4.10.1"
 
-    ANTLR4_RUNTIME_GIT_SHA = "70b2edcf98eb612a92d3dbaedb2ce0b69533b0cb"  # Dec 7, 2021
-    ANTLR4_RUNTIME_SHA = "fae73909f95e1320701e29ac03bab9233293fb5b90d3ce857279f1b46b614c83"
     http_archive(
         name = "antlr4_runtimes",
         build_file_content = """
@@ -89,9 +83,14 @@ cc_library(
     includes = ["runtime/Cpp/runtime/src"],
 )
   """,
-        sha256 = ANTLR4_RUNTIME_SHA,
-        strip_prefix = "antlr4-" + ANTLR4_RUNTIME_GIT_SHA,
-        urls = ["https://github.com/antlr/antlr4/archive/" + ANTLR4_RUNTIME_GIT_SHA + ".tar.gz"],
+        sha256 = "a320568b738e42735946bebc5d9d333170e14a251c5734e8b852ad1502efa8a2",
+        strip_prefix = "antlr4-" + ANTLR4_VERSION,
+        urls = ["https://github.com/antlr/antlr4/archive/v" + ANTLR4_VERSION + ".tar.gz"],
+    )
+    http_jar(
+        name = "antlr4_jar",
+        urls = ["https://www.antlr.org/download/antlr-" + ANTLR4_VERSION + "-complete.jar"],
+        sha256 = "41949d41f20d31d5b8277187735dd755108df52b38db6c865108d3382040f918",
     )
 
 def flatbuffers_deps():

bazel/deps_extra.bzl

@@ -4,7 +4,6 @@ Transitive dependencies.
 
 load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
 load("@com_google_googleapis//:repository_rules.bzl", "switched_rules_by_language")
-load("@rules_antlr//antlr:repositories.bzl", "rules_antlr_dependencies")
 load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_dependencies")
 load("@bazel_gazelle//:deps.bzl", "gazelle_dependencies", "go_repository")
 
@@ -50,5 +49,4 @@ def cel_cpp_deps_extra():
         cc = True,
         go = True,  # cel-spec requirement
     )
-    rules_antlr_dependencies("4.8")
     cel_spec_deps_extra()

parser/parser.cc

@@ -43,9 +43,9 @@
 #include "internal/strings.h"
 #include "internal/unicode.h"
 #include "internal/utf8.h"
-#include "parser/internal/cel_grammar.inc/cel_parser_internal/CelBaseVisitor.h"
-#include "parser/internal/cel_grammar.inc/cel_parser_internal/CelLexer.h"
-#include "parser/internal/cel_grammar.inc/cel_parser_internal/CelParser.h"
+#include "parser/internal/CelBaseVisitor.h"
+#include "parser/internal/CelLexer.h"
+#include "parser/internal/CelParser.h"
 #include "parser/macro.h"
 #include "parser/options.h"
 #include "parser/source_factory.h"

parser/source_factory.h

@@ -24,7 +24,7 @@
 #include "absl/strings/string_view.h"
 #include "absl/types/optional.h"
 #include "antlr4-runtime.h"
-#include "parser/internal/cel_grammar.inc/cel_parser_internal/CelParser.h"
+#include "parser/internal/CelParser.h"
 
 namespace google::api::expr::parser {