[1.8] htmlhelp: convert hex escaping to decimal escaping in .hhc/.hhk files (#5853)

* htmlhelp: convert hex escaping to decimal escaping in .hhc/.hhk files

.hhc/.hhk files don't recognize hex escaping, we need convert hex escaping to decimal escaping. for example: `'` -> `'`.

tests/roots/test-build-htmlhelp/conf.py

@@ -0,0 +1,4 @@
+# -*- coding: utf-8 -*-
+
+project = 'test'
+master_doc = 'index'

tests/roots/test-build-htmlhelp/index.rst

@@ -0,0 +1,19 @@
+Index markup
+------------
+
+.. index::
+   single: entry
+   pair: entry; pair
+   double: entry; double
+   triple: index; entry; triple
+   keyword: with
+   see: from; to
+   seealso: fromalso; toalso
+
+.. index::
+   !Main, !Other
+   !single: entry; pair
+
+.. index:: triple-quoted string, Unicode Consortium, raw string
+   single: """; string literal
+   single: '''; string literal

tests/roots/test-build-htmlhelp/make.bat

@@ -0,0 +1,64 @@
+@echo off
+setlocal
+
+pushd %~dp0
+
+set this=%~n0
+
+if not defined PYTHON set PYTHON=py
+
+if not defined SPHINXBUILD (
+    %PYTHON% -c "import sphinx" > nul 2> nul
+    if errorlevel 1 (
+        echo Installing sphinx with %PYTHON%
+        %PYTHON% -m pip install sphinx
+        if errorlevel 1 exit /B
+    )
+    set SPHINXBUILD=%PYTHON% -c "import sphinx.cmd.build, sys; sys.exit(sphinx.cmd.build.main())"
+)
+
+rem Search for HHC in likely places
+set HTMLHELP=
+where hhc /q && set HTMLHELP=hhc && goto :skiphhcsearch
+where /R ..\externals hhc > "%TEMP%\hhc.loc" 2> nul && set /P HTMLHELP= < "%TEMP%\hhc.loc" & del "%TEMP%\hhc.loc"
+if not exist "%HTMLHELP%" where /R "%ProgramFiles(x86)%" hhc > "%TEMP%\hhc.loc" 2> nul && set /P HTMLHELP= < "%TEMP%\hhc.loc" & del "%TEMP%\hhc.loc"
+if not exist "%HTMLHELP%" where /R "%ProgramFiles%" hhc > "%TEMP%\hhc.loc" 2> nul && set /P HTMLHELP= < "%TEMP%\hhc.loc" & del "%TEMP%\hhc.loc"
+if not exist "%HTMLHELP%" (
+    echo.
+    echo.The HTML Help Workshop was not found.  Set the HTMLHELP variable
+    echo.to the path to hhc.exe or download and install it from
+    echo.http://msdn.microsoft.com/en-us/library/ms669985
+    exit /B 1
+)
+echo hhc.exe path: %HTMLHELP%
+
+if "%BUILDDIR%" EQU "" set BUILDDIR=build
+
+%SPHINXBUILD% >nul 2> nul
+if errorlevel 9009 (
+    echo.
+    echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
+    echo.installed, then set the SPHINXBUILD environment variable to point
+    echo.to the full path of the 'sphinx-build' executable. Alternatively you
+    echo.may add the Sphinx directory to PATH.
+    popd
+    exit /B 1
+)
+
+set SPHINXOPTS=-D html_theme_options.body_max_width=none %SPHINXOPTS%
+
+cmd /S /C "%SPHINXBUILD% %SPHINXOPTS% -bhtmlhelp -dbuild\doctrees . "%BUILDDIR%\htmlhelp"
+
+"%HTMLHELP%" "%BUILDDIR%\htmlhelp\test.hhp"
+rem hhc.exe seems to always exit with code 1, reset to 0 for less than 2
+if not errorlevel 2 cmd /C exit /b 0
+
+echo.
+if errorlevel 1 (
+    echo.Build failed (exit code %ERRORLEVEL%^), check for error messages
+    echo.above.  Any output will be found in %BUILDDIR%\%1
+) else (
+    echo.Build succeeded. All output should be in %BUILDDIR%\%1
+)
+
+popd