feat: Add opt-in PCRE2 regex engine and Java-regex compatibility test suite

CMake/Findpcre2.cmake

@@ -0,0 +1,55 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Locate a system PCRE2 installation (8-bit code unit width) and expose it
+# under the canonical target name `pcre2-8::pcre2-8` used by the
+# velox/external/regex_compat module.
+
+find_package(PCRE2 QUIET CONFIG COMPONENTS 8BIT)
+if(PCRE2_FOUND)
+  if(NOT TARGET pcre2-8::pcre2-8 AND TARGET PCRE2::8BIT)
+    add_library(pcre2-8::pcre2-8 ALIAS PCRE2::8BIT)
+  endif()
+  message(STATUS "Found PCRE2 via CMake.")
+  return()
+endif()
+
+if(TARGET pcre2-8::pcre2-8)
+  message(STATUS "PCRE2 target already defined.")
+  return()
+endif()
+
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(PCRE2_8 QUIET libpcre2-8)
+if(PCRE2_8_FOUND)
+  add_library(pcre2-8::pcre2-8 INTERFACE IMPORTED)
+  set_property(
+    TARGET pcre2-8::pcre2-8
+    PROPERTY INTERFACE_INCLUDE_DIRECTORIES "${PCRE2_8_INCLUDE_DIRS}"
+  )
+  set_property(TARGET pcre2-8::pcre2-8 PROPERTY INTERFACE_LINK_LIBRARIES "${PCRE2_8_LDFLAGS}")
+  set_property(
+    TARGET pcre2-8::pcre2-8
+    PROPERTY INTERFACE_COMPILE_DEFINITIONS "PCRE2_CODE_UNIT_WIDTH=8"
+  )
+  set(pcre2_FOUND TRUE)
+  message(STATUS "Found PCRE2 via pkg-config.")
+  return()
+endif()
+
+if(pcre2_FIND_REQUIRED)
+  message(FATAL_ERROR "Failed to find PCRE2.")
+elseif(NOT pcre2_FIND_QUIETLY)
+  message(WARNING "Failed to find PCRE2.")
+endif()

CMake/resolve_dependency_modules/pcre2.cmake

@@ -0,0 +1,55 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+include_guard(GLOBAL)
+
+if(DEFINED ENV{VELOX_PCRE2_URL})
+  set(VELOX_PCRE2_SOURCE_URL "$ENV{VELOX_PCRE2_URL}")
+else()
+  set(VELOX_PCRE2_VERSION 10.47)
+  set(
+    VELOX_PCRE2_SOURCE_URL
+    "https://github.com/PCRE2Project/pcre2/releases/download/pcre2-${VELOX_PCRE2_VERSION}/pcre2-${VELOX_PCRE2_VERSION}.tar.gz"
+  )
+  set(
+    VELOX_PCRE2_BUILD_SHA256_CHECKSUM
+    c08ae2388ef333e8403e670ad70c0a11f1eed021fd88308d7e02f596fcd9dc16
+  )
+endif()
+
+message(STATUS "Building PCRE2 ${VELOX_PCRE2_VERSION} from source")
+FetchContent_Declare(
+  pcre2
+  URL ${VELOX_PCRE2_SOURCE_URL}
+  URL_HASH SHA256=${VELOX_PCRE2_BUILD_SHA256_CHECKSUM}
+)
+
+set(PCRE2_BUILD_PCRE2_8 ON CACHE BOOL "" FORCE)
+set(PCRE2_BUILD_PCRE2_16 OFF CACHE BOOL "" FORCE)
+set(PCRE2_BUILD_PCRE2_32 OFF CACHE BOOL "" FORCE)
+set(PCRE2_SUPPORT_JIT ON CACHE BOOL "" FORCE)
+set(PCRE2_BUILD_TESTS OFF CACHE BOOL "" FORCE)
+set(PCRE2_BUILD_PCRE2GREP OFF CACHE BOOL "" FORCE)
+set(PCRE2_SUPPORT_UNICODE ON CACHE BOOL "" FORCE)
+set(PCRE2_STATIC_PIC ON CACHE BOOL "" FORCE)
+
+FetchContent_MakeAvailable(pcre2)
+
+# Normalise the target name so consumers always link `pcre2-8::pcre2-8`.
+if(TARGET pcre2-8-static AND NOT TARGET pcre2-8::pcre2-8)
+  add_library(pcre2-8::pcre2-8 ALIAS pcre2-8-static)
+elseif(TARGET pcre2-8 AND NOT TARGET pcre2-8::pcre2-8)
+  add_library(pcre2-8::pcre2-8 ALIAS pcre2-8)
+endif()
+
+unset(BUILD_TESTING CACHE)

CMakeLists.txt

@@ -142,6 +142,16 @@ option(VELOX_ENABLE_TPCDS_CONNECTOR "Build TPC-DS connector." ON)
 option(VELOX_ENABLE_PRESTO_FUNCTIONS "Build Presto SQL functions." ON)
 option(VELOX_ENABLE_SPARK_FUNCTIONS "Build Spark SQL functions." ON)
 option(VELOX_ENABLE_ICEBERG_FUNCTIONS "Build Iceberg functions." ON)
+option(
+  VELOX_ENABLE_REGEX_COMPAT_TESTS
+  "Build the PCRE2 vs RE2 Java-regex compatibility test suite (pulls in PCRE2 dep)."
+  OFF
+)
+option(
+  VELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND
+  "Within the regex-compat test suite, also exercise an embedded-JVM Java backend as a third backend / oracle. Requires JDK on the build host. If JNI cannot be found, this option is auto-disabled with a warning. Only consulted when VELOX_ENABLE_REGEX_COMPAT_TESTS=ON."
+  ON
+)
 option(VELOX_ENABLE_EXPRESSION "Build expression." ON)
 option(
   VELOX_ENABLE_EXAMPLES
@@ -626,6 +636,30 @@ endif()
 velox_set_source(re2)
 velox_resolve_dependency(re2)
 
+if(VELOX_ENABLE_REGEX_COMPAT_TESTS)
+  velox_set_source(pcre2)
+  velox_resolve_dependency(pcre2)
+
+  if(VELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND)
+    # Probe for a JDK so the test suite can embed a JVM as a third (oracle)
+    # backend.  This is the only place in upstream Velox that touches JNI, and
+    # it is fully opt-in (gated by the regex-compat option above).  If JNI is
+    # not found we silently degrade — the test suite still builds with the
+    # PCRE2 + RE2 backends only.
+    find_package(JNI QUIET)
+    if(JNI_FOUND)
+      message(STATUS "Regex-compat: enabling embedded-JVM Java backend (JNI: ${JNI_INCLUDE_DIRS})")
+    else()
+      message(
+        WARNING
+        "Regex-compat: JNI not found, disabling Java backend. "
+        "Install a JDK or pass -DVELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND=OFF to silence."
+      )
+      set(VELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND OFF CACHE BOOL "" FORCE)
+    endif()
+  endif()
+endif()
+
 if(${VELOX_BUILD_PYTHON_PACKAGE})
   find_package(Python 3.9 COMPONENTS Interpreter Development.Module REQUIRED)
   velox_set_source(pybind11)

velox/CMakeLists.txt

@@ -26,6 +26,9 @@ add_subdirectory(external/date)
 add_subdirectory(external/tzdb)
 add_subdirectory(external/md5)
 add_subdirectory(external/hdfs)
+if(VELOX_ENABLE_REGEX_COMPAT_TESTS)
+  add_subdirectory(external/regex_compat)
+endif()
 #
 
 # examples depend on expression

velox/external/regex_compat/CMakeLists.txt

@@ -0,0 +1,42 @@
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Only entered when VELOX_ENABLE_REGEX_COMPAT_TESTS=ON.
+
+set(_REGEX_COMPAT_SRC Re2Regex.cpp Pcre2Regex.cpp)
+set(_REGEX_COMPAT_LIBS re2::re2 pcre2-8::pcre2-8)
+
+if(VELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND)
+  list(APPEND _REGEX_COMPAT_SRC JvmFixture.cpp JavaRegex.cpp)
+  list(APPEND _REGEX_COMPAT_LIBS ${JNI_LIBRARIES})
+endif()
+
+velox_add_library(velox_regex_compat ${_REGEX_COMPAT_SRC})
+
+velox_link_libraries(velox_regex_compat
+  PUBLIC ${_REGEX_COMPAT_LIBS}
+  PRIVATE velox_functions_lib velox_java_pcre2_translator)
+
+if(VELOX_ENABLE_REGEX_COMPAT_JAVA_BACKEND)
+  velox_include_directories(velox_regex_compat PUBLIC ${JNI_INCLUDE_DIRS})
+  velox_compile_definitions(velox_regex_compat
+    PUBLIC VELOX_REGEX_COMPAT_HAS_JAVA=1)
+else()
+  velox_compile_definitions(velox_regex_compat
+    PUBLIC VELOX_REGEX_COMPAT_HAS_JAVA=0)
+endif()
+
+if(${VELOX_BUILD_TESTING})
+  add_subdirectory(tests)
+endif()