Make sure $$relative_path() uses an absolute path as its first arg

Thanks to QTBUG-61373, this qmake function was called with
/usr/local/5.10.1 as baseDir, which isn't absolute, leading to an
assertion failure.  We could raise the error within qmake but it
proved easier to simply resolve any non-absolute baseDir using PWD,
before trying to use it as an absolute path.

Did the same for $$absolute_path().  Documented both.  Adjusted the
assert that caught this to report any non-absolute path that upsets
it.  Added simple tests, fixed an existing test.

Task-number: QTBUG-66156
Change-Id: Icfef2e2f5b236e071177c9beffa38d71bf404292
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>

1 files changed, 6 insertions, 2 deletions

diff --git a/qmake/library/qmakebuiltins.cpp b/qmake/library/qmakebuiltins.cpp
index 83c3d1d643..0a83b9b930 100644
--- a/qmake/library/qmakebuiltins.cpp
+++ b/qmake/library/qmakebuiltins.cpp
@@ -1178,7 +1178,9 @@ QMakeEvaluator::VisitReturn QMakeEvaluator::evaluateBuiltinExpand(
             evalError(fL1S("absolute_path(path[, base]) requires one or two arguments."));
         } else {
             QString arg = args.at(0).toQString(m_tmp1);
-            QString baseDir = args.count() > 1 ? args.at(1).toQString(m_tmp2) : currentDirectory();
+            QString baseDir = args.count() > 1
+                    ? IoUtils::resolvePath(currentDirectory(), args.at(1).toQString(m_tmp2))
+                    : currentDirectory();
             QString rstr = arg.isEmpty() ? baseDir : IoUtils::resolvePath(baseDir, arg);
             ret << (rstr.isSharedWith(m_tmp1)
                         ? args.at(0)
@@ -1192,7 +1194,9 @@ QMakeEvaluator::VisitReturn QMakeEvaluator::evaluateBuiltinExpand(
             evalError(fL1S("relative_path(path[, base]) requires one or two arguments."));
         } else {
             QString arg = args.at(0).toQString(m_tmp1);
-            QString baseDir = args.count() > 1 ? args.at(1).toQString(m_tmp2) : currentDirectory();
+            QString baseDir = args.count() > 1
+                    ? IoUtils::resolvePath(currentDirectory(), args.at(1).toQString(m_tmp2))
+                    : currentDirectory();
             QString absArg = arg.isEmpty() ? baseDir : IoUtils::resolvePath(baseDir, arg);
             QString rstr = QDir(baseDir).relativeFilePath(absArg);
             ret << (rstr.isSharedWith(m_tmp1) ? args.at(0) : ProString(rstr).setSource(args.at(0)));