CMake: pro2cmake.py: Warn and fix broken line continuation

Warn on broken line continuation in .pro-files, but fix up the issue
and proceed.

Change-Id: Ibe68011b312bcea25620ce790a0b44b2983fbd88
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

util/cmake/pro2cmake.py

@@ -72,6 +72,13 @@ def _parse_commandline():
     return parser.parse_args()
 
 
+def fixup_linecontinuation(contents: str) -> str:
+    contents = re.sub(r'([^\t ])\\[ \t]*\n', '\\1 \\\n', contents)
+    contents = re.sub(r'\\[ \t]*\n', '\\\n', contents)
+
+    return contents
+
+
 def spaces(indent: int) -> str:
     return '    ' * indent
 
@@ -622,7 +629,16 @@ class QmakeParser:
     def parseFile(self, file: str):
         print('Parsing \"{}\"...'.format(file))
         try:
-            result = self._Grammar.parseFile(file, parseAll=True)
+            with open(file, 'r') as file_fd:
+                contents = file_fd.read()
+
+            old_contents = contents
+            contents = fixup_linecontinuation(contents)
+
+            if old_contents != contents:
+                print('Warning: Fixed line continuation in .pro-file!\n'
+                      '         Position information in Parsing output might be wrong!')
+            result = self._Grammar.parseString(contents, parseAll=True)
         except pp.ParseException as pe:
             print(pe.line)
             print(' '*(pe.col-1) + '^')

util/cmake/tests/test_lc_fixup.py

@@ -0,0 +1,46 @@
+#!/usr/bin/env python3
+#############################################################################
+##
+## Copyright (C) 2018 The Qt Company Ltd.
+## Contact: https://www.qt.io/licensing/
+##
+## This file is part of the plugins of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:GPL-EXCEPT$
+## Commercial License Usage
+## Licensees holding valid commercial Qt licenses may use this file in
+## accordance with the commercial license agreement provided with the
+## Software or, alternatively, in accordance with the terms contained in
+## a written agreement between you and The Qt Company. For licensing terms
+## and conditions see https://www.qt.io/terms-conditions. For further
+## information use the contact form at https://www.qt.io/contact-us.
+##
+## GNU General Public License Usage
+## Alternatively, this file may be used under the terms of the GNU
+## General Public License version 3 as published by the Free Software
+## Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+## included in the packaging of this file. Please review the following
+## information to ensure the GNU General Public License requirements will
+## be met: https://www.gnu.org/licenses/gpl-3.0.html.
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+from pro2cmake import fixup_linecontinuation
+
+from textwrap import dedent
+
+
+def test_no_change():
+    input = "test \\\nline2\n  line3"
+    result = fixup_linecontinuation(input)
+    assert input == result
+
+
+def test_fix():
+    input = "test \\\t\nline2\\\n  line3\\ \nline4 \\ \t\nline5\\\n\n\n"
+    result = fixup_linecontinuation(input)
+    assert 'test \\\nline2 \\\n  line3 \\\nline4 \\\nline5 \\\n\n\n' == result
+
+