From 2a8df712a1275f9ad3cf8853998853cc8546baec Mon Sep 17 00:00:00 2001
From: Sergey Fedorov <barracuda@macos-powerpc.org>
Date: Wed, 12 Aug 2026 18:53:08 +0000
Subject: [PATCH] Qt4: locate QtSingleApplication by fixed path, not
 find_path/find_library

The qtsingleapplication-qt4 MacPorts port installs no CMake package
config or module, and find_path()/find_library() weren't reliably
locating it either. Since the Portfile will declare a dependency on
qtsingleapplication-qt4, its presence under the Qt4 kit's own
include/lib dirs can just be assumed, so address it directly:
  ${QT_INCLUDE_DIR}/QtSingleApplication/QtSingleApplication
  ${QT_LIBRARY_DIR}/libQtSingleApplication.dylib
(matching the actual port layout), with an EXISTS check for a clear
error message if that assumption ever doesn't hold.

Also fixes the imported target's type: the port installs a shared
.dylib, not a static .a, so it must be `SHARED IMPORTED` rather than
`STATIC IMPORTED` -- the previous commit copied the STATIC form from
the qt-solutions ExternalProject build, which does produce a .a.
---
 CMake/Includes/ProjectExternals.cmake | 28 ++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/CMake/Includes/ProjectExternals.cmake b/CMake/Includes/ProjectExternals.cmake
index 4f807e2..5d05afb 100644
--- a/CMake/Includes/ProjectExternals.cmake
+++ b/CMake/Includes/ProjectExternals.cmake
@@ -40,26 +40,28 @@ if(WITH_QT4)
     # qt-solutions' own CMakeLists.txt (CMakeLists_qt-solutions.cmake.in)
     # hardcodes Qt6, so under Qt4 use the prebuilt MacPorts
     # devel/qtsingleapplication-qt4 port instead of building it ourselves.
-    find_path(QTSINGLEAPPLICATION_INCLUDE_DIR
-        NAMES QtSingleApplication
-        PATH_SUFFIXES QtSingleApplication
-        HINTS ${QT_INCLUDE_DIR}
-    )
-    find_library(QTSINGLEAPPLICATION_LIBRARY
-        NAMES QtSingleApplication
-        HINTS ${QT_LIBRARY_DIR}
-    )
-    if(NOT QTSINGLEAPPLICATION_INCLUDE_DIR OR NOT QTSINGLEAPPLICATION_LIBRARY)
-        message(FATAL_ERROR "Could NOT find QtSingleApplication! Install it with e.g. 'port install qtsingleapplication-qt4'")
+    # That port ships no CMake package config/module of its own (and
+    # find_path()/find_library() don't reliably locate it either), so
+    # its files are addressed directly under the Qt4 kit's own
+    # include/lib dirs. The MacPorts Portfile is expected to declare a
+    # dependency on qtsingleapplication-qt4, so its presence there can
+    # be assumed rather than searched for.
+    set(QTSINGLEAPPLICATION_INCLUDE_DIR "${QT_INCLUDE_DIR}/QtSingleApplication")
+    set(QTSINGLEAPPLICATION_LIBRARY "${QT_LIBRARY_DIR}/libQtSingleApplication.dylib")
+    if(NOT EXISTS "${QTSINGLEAPPLICATION_INCLUDE_DIR}/QtSingleApplication" OR NOT EXISTS "${QTSINGLEAPPLICATION_LIBRARY}")
+        message(FATAL_ERROR "QtSingleApplication not found under the Qt4 kit "
+            "(looked for ${QTSINGLEAPPLICATION_INCLUDE_DIR}/QtSingleApplication and ${QTSINGLEAPPLICATION_LIBRARY}); "
+            "install it with e.g. 'port install qtsingleapplication-qt4'")
     endif()
     message(STATUS "Library 'QtSingleApplication' found at ${QTSINGLEAPPLICATION_LIBRARY}")
 
-    add_library(qt-solutions::qtsingleapplication STATIC IMPORTED)
+    # The port installs a shared .dylib (not a static .a), unlike the
+    # qt-solutions ExternalProject build below.
+    add_library(qt-solutions::qtsingleapplication SHARED IMPORTED)
     set_target_properties(qt-solutions::qtsingleapplication PROPERTIES
         INTERFACE_INCLUDE_DIRECTORIES "${QTSINGLEAPPLICATION_INCLUDE_DIR}"
         IMPORTED_LOCATION "${QTSINGLEAPPLICATION_LIBRARY}"
     )
-    mark_as_advanced(QTSINGLEAPPLICATION_INCLUDE_DIR QTSINGLEAPPLICATION_LIBRARY)
 else()
     include(ProjectExternals_qt-solutions)
 endif()
-- 
2.43.0