Merge bitcoin/bitcoin#33209: cmake: Drop python dependency for translate

3c4a109aa8 cmake: Drop python dependency for translate (Daniel Pfeifer)

Pull request description:

  Translate the `share/qt/extract_strings_qt.py` script to CMake. This removes the python dependency from the `translate` target.

  Resolves #33146

ACKs for top commit:
  hebasto:
    re-ACK 3c4a109aa8.
  janb84:
    re ACK 3c4a109aa8

Tree-SHA512: 4fda8efd4301c49eef8bf2908073475fcff3f995cf6860187f8d08821559612303b303052c1e54a01ad31703fe63aea01e999d08f5471f2c479c97de8c240605

share/qt/extract_strings_qt.py

@@ -1,85 +0,0 @@
-#!/usr/bin/env python3
-# Copyright (c) 2012-2021 The Bitcoin Core developers
-# Distributed under the MIT software license, see the accompanying
-# file COPYING or http://www.opensource.org/licenses/mit-license.php.
-'''
-Extract _("...") strings for translation and convert to Qt stringdefs so that
-they can be picked up by Qt linguist.
-'''
-from subprocess import Popen, PIPE
-import operator
-import os
-import sys
-
-OUT_CPP="qt/bitcoinstrings.cpp"
-EMPTY=['""']
-
-def parse_po(text):
-    """
-    Parse 'po' format produced by xgettext.
-    Return a list of (msgid,msgstr) tuples.
-    """
-    messages = []
-    msgid = []
-    msgstr = []
-    in_msgid = False
-    in_msgstr = False
-
-    for line in text.split('\n'):
-        line = line.rstrip('\r')
-        if line.startswith('msgid '):
-            if in_msgstr:
-                messages.append((msgid, msgstr))
-                in_msgstr = False
-            # message start
-            in_msgid = True
-
-            msgid = [line[6:]]
-        elif line.startswith('msgstr '):
-            in_msgid = False
-            in_msgstr = True
-            msgstr = [line[7:]]
-        elif line.startswith('"'):
-            if in_msgid:
-                msgid.append(line)
-            if in_msgstr:
-                msgstr.append(line)
-
-    if in_msgstr:
-        messages.append((msgid, msgstr))
-
-    return messages
-
-files = sys.argv[1:]
-
-# xgettext -n --keyword=_ $FILES
-XGETTEXT=os.getenv('XGETTEXT', 'xgettext')
-if not XGETTEXT:
-    print('Cannot extract strings: xgettext utility is not installed or not configured.',file=sys.stderr)
-    print('Please install package "gettext" and re-run \'cmake -B build\'.',file=sys.stderr)
-    sys.exit(1)
-child = Popen([XGETTEXT,'--output=-','--from-code=utf-8','-n','--keyword=_'] + files, stdout=PIPE)
-(out, err) = child.communicate()
-
-messages = parse_po(out.decode('utf-8'))
-
-f = open(OUT_CPP, 'w', encoding="utf8")
-f.write("""
-
-#include <QtGlobal>
-
-// Automatically generated by extract_strings_qt.py
-#ifdef __GNUC__
-#define UNUSED __attribute__((unused))
-#else
-#define UNUSED
-#endif
-""")
-f.write('static const char UNUSED *bitcoin_strings[] = {\n')
-f.write('QT_TRANSLATE_NOOP("bitcoin-core", "%s"),\n' % (os.getenv('COPYRIGHT_HOLDERS'),))
-messages.sort(key=operator.itemgetter(0))
-for (msgid, msgstr) in messages:
-    if msgid != EMPTY:
-        f.write('QT_TRANSLATE_NOOP("bitcoin-core", %s),\n' % ('\n'.join(msgid)))
-f.write('};\n')
-f.close()

share/qt/translate.cmake

@@ -2,12 +2,13 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+cmake_minimum_required(VERSION 3.22)
+
 set(input_variables
   PROJECT_SOURCE_DIR
   COPYRIGHT_HOLDERS
   LCONVERT_EXECUTABLE
   LUPDATE_EXECUTABLE
-  PYTHON_EXECUTABLE
   XGETTEXT_EXECUTABLE
 )
 
@@ -17,6 +18,60 @@ foreach(var IN LISTS input_variables)
   endif()
 endforeach()
 
+# Extract _("...") strings for translation and convert to Qt stringdefs so that
+# they can be picked up by Qt linguist.
+function(extract_strings output)
+  execute_process(
+    COMMAND ${XGETTEXT_EXECUTABLE}
+      --output=bitcoinstrings.po
+      --no-location
+      --from-code=utf-8
+      --keyword=_
+      ${ARGN}
+    COMMAND_ERROR_IS_FATAL ANY
+  )
+
+  file(STRINGS "bitcoinstrings.po" text ENCODING "UTF-8")
+
+  set(messages "${COPYRIGHT_HOLDERS}")
+  foreach(line IN LISTS text)
+    if(line MATCHES "^msgid \"(.*)\"$")
+      set(msgid "${CMAKE_MATCH_1}")
+    elseif(line MATCHES "^\"(.*)\"$")
+      string(APPEND msgid "${CMAKE_MATCH_1}")
+    elseif(line MATCHES "^msgstr .*$" AND NOT msgid STREQUAL "")
+      # CMake uses ';' as a list separator.
+      # We need to temporarily replace that in order to keep strings intact.
+      string(REPLACE ";" "<cmake-semicolon>" msgid "${msgid}")
+      list(APPEND messages "${msgid}")
+    endif()
+  endforeach()
+
+  set(content [[// Automatically generated by translate.cmake
+
+#include <QtGlobal>
+
+#ifdef __GNUC__
+#define UNUSED __attribute__((unused))
+#else
+#define UNUSED
+#endif
+
+static const char UNUSED *bitcoin_strings[] = {
+]])
+
+  set(prefix "QT_TRANSLATE_NOOP(\"bitcoin-core\", \"")
+  set(suffix "\"),\n")
+
+  list(SORT messages)
+  list(JOIN messages "${suffix}${prefix}" messages_str)
+  string(APPEND content "${prefix}${messages_str}${suffix}")
+  string(APPEND content "};\n")
+  string(REPLACE "<cmake-semicolon>" ";" content "${content}")
+
+  file(WRITE "${output}" "${content}")
+endfunction()
+
 file(GLOB_RECURSE translatable_sources
   "${PROJECT_SOURCE_DIR}/src/*.h"
   "${PROJECT_SOURCE_DIR}/src/*.cpp"
@@ -41,15 +96,8 @@ foreach(directory IN LISTS subtrees exclude_dirs)
   )
 endforeach()
 
-execute_process(
+extract_strings("${PROJECT_SOURCE_DIR}/src/qt/bitcoinstrings.cpp"
-  COMMAND ${CMAKE_COMMAND} -E env
+  ${translatable_sources}
-    XGETTEXT=${XGETTEXT_EXECUTABLE}
-    COPYRIGHT_HOLDERS=${COPYRIGHT_HOLDERS}
-    ${PYTHON_EXECUTABLE}
-    ${CMAKE_CURRENT_LIST_DIR}/extract_strings_qt.py
-    ${translatable_sources}
-  WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/src
-  COMMAND_ERROR_IS_FATAL ANY
 )
 
 execute_process(

src/qt/CMakeLists.txt

@@ -300,7 +300,6 @@ else()
     -D "COPYRIGHT_HOLDERS=${COPYRIGHT_HOLDERS}"
     -D "LCONVERT_EXECUTABLE=$<TARGET_FILE:Qt6::lconvert>"
     -D "LUPDATE_EXECUTABLE=$<TARGET_FILE:Qt6::lupdate>"
-    -D "PYTHON_EXECUTABLE=$<TARGET_FILE:Python3::Interpreter>"
     -D "XGETTEXT_EXECUTABLE=${XGETTEXT_EXECUTABLE}"
     -P ${PROJECT_SOURCE_DIR}/share/qt/translate.cmake
   )