From 4f3b97063f724f5e0a2902e8d2c104012b52b7f5 Mon Sep 17 00:00:00 2001
From: Domen Vrankar <domen.vrankar@gmail.com>
Date: Mon, 23 May 2016 20:21:32 +0200
Subject: [PATCH] CPack/Deb prevent accidental component dependencies

Prevent accidental inter component dependency setting
since this is a breaking feature in situations where
another CPack module is already using the feature.
It should be enabled if desired since it can cause
issues when upgrading only one of the components
for e.g. configuration instead of all the components
at once.
---
 Help/release/dev/cpack-deb-imporvements.rst   |  3 +-
 Modules/CPackDeb.cmake                        | 36 ++++++++++++-------
 ...LibCPackConfig-components-depend1.cmake.in |  1 +
 ...LibCPackConfig-components-depend2.cmake.in |  1 +
 4 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/Help/release/dev/cpack-deb-imporvements.rst b/Help/release/dev/cpack-deb-imporvements.rst
index 4fd35b898..9e45aa546 100644
--- a/Help/release/dev/cpack-deb-imporvements.rst
+++ b/Help/release/dev/cpack-deb-imporvements.rst
@@ -11,7 +11,8 @@ cpack-deb-imporvements
 * The :module:`CPackDeb` module learned how to generate dependencies between
   Debian packages if multi-component setup is used and
   :variable:`CPACK_COMPONENT_<compName>_DEPENDS` variables are set.
-  This breaks compatibility with previous versions.
+  For backward compatibility this feature is disabled by default. See
+  :variable:`CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS`.
 
 * The :module:`CPackDeb` module learned how to set the package release number
   (``DebianRevisionNumber`` in package file name).  See
diff --git a/Modules/CPackDeb.cmake b/Modules/CPackDeb.cmake
index d93d924a8..70bf81dd2 100644
--- a/Modules/CPackDeb.cmake
+++ b/Modules/CPackDeb.cmake
@@ -100,6 +100,13 @@
 #
 #    set(CPACK_DEBIAN_PACKAGE_DEPENDS "libc6 (>= 2.3.1-6), libc6 (< 2.4)")
 #
+# .. variable:: CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS
+#
+#  Sets inter component dependencies if listed with
+#  :variable:`CPACK_COMPONENT_<compName>_DEPENDS` variables.
+#
+#  * Mandatory : NO
+#  * Default   : -
 #
 # .. variable:: CPACK_DEBIAN_PACKAGE_MAINTAINER
 #
@@ -713,20 +720,23 @@ function(cpack_deb_prepare_package_vars)
         endif()
       endif()
     endforeach()
-    set(COMPONENT_DEPENDS "")
-    foreach (_PACK ${CPACK_COMPONENT_${_local_component_name}_DEPENDS})
-      get_component_package_name(_PACK_NAME "${_PACK}")
+
+    if(CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS)
+      set(COMPONENT_DEPENDS "")
+      foreach (_PACK ${CPACK_COMPONENT_${_local_component_name}_DEPENDS})
+        get_component_package_name(_PACK_NAME "${_PACK}")
+        if(COMPONENT_DEPENDS)
+          set(COMPONENT_DEPENDS "${_PACK_NAME} (= ${CPACK_DEBIAN_PACKAGE_VERSION}), ${COMPONENT_DEPENDS}")
+        else()
+          set(COMPONENT_DEPENDS "${_PACK_NAME} (= ${CPACK_DEBIAN_PACKAGE_VERSION})")
+        endif()
+      endforeach()
       if(COMPONENT_DEPENDS)
-        set(COMPONENT_DEPENDS "${_PACK_NAME} (= ${CPACK_DEBIAN_PACKAGE_VERSION}), ${COMPONENT_DEPENDS}")
-      else()
-        set(COMPONENT_DEPENDS "${_PACK_NAME} (= ${CPACK_DEBIAN_PACKAGE_VERSION})")
-      endif()
-    endforeach()
-    if(COMPONENT_DEPENDS)
-      if(CPACK_DEBIAN_PACKAGE_DEPENDS)
-        set(CPACK_DEBIAN_PACKAGE_DEPENDS "${COMPONENT_DEPENDS}, ${CPACK_DEBIAN_PACKAGE_DEPENDS}")
-      else()
-        set(CPACK_DEBIAN_PACKAGE_DEPENDS "${COMPONENT_DEPENDS}")
+        if(CPACK_DEBIAN_PACKAGE_DEPENDS)
+          set(CPACK_DEBIAN_PACKAGE_DEPENDS "${COMPONENT_DEPENDS}, ${CPACK_DEBIAN_PACKAGE_DEPENDS}")
+        else()
+          set(CPACK_DEBIAN_PACKAGE_DEPENDS "${COMPONENT_DEPENDS}")
+        endif()
       endif()
     endif()
   endif()
diff --git a/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend1.cmake.in b/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend1.cmake.in
index d207bcc12..dc038fa4c 100644
--- a/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend1.cmake.in
+++ b/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend1.cmake.in
@@ -4,6 +4,7 @@
 
 if(CPACK_GENERATOR MATCHES "DEB")
    set(CPACK_DEB_COMPONENT_INSTALL "ON")
+   set(CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS "ON")
 endif()
 
 #
diff --git a/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend2.cmake.in b/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend2.cmake.in
index 803720a3c..1aa7d0199 100644
--- a/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend2.cmake.in
+++ b/Tests/CPackComponentsDEB/MyLibCPackConfig-components-depend2.cmake.in
@@ -4,6 +4,7 @@
 
 if(CPACK_GENERATOR MATCHES "DEB")
    set(CPACK_DEB_COMPONENT_INSTALL "ON")
+   set(CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS "ON")
 endif()
 
 #