Support org-prefixed package names in find_package

CPM.cmake now attempts to locate packages using organization-prefixed names (e.g., org-library) if the standard name is not found. This helps resolve naming conflicts and improves compatibility with packages installed under organization-qualified names. Documentation has been updated to reflect this behavior.

Author: sean-parent

README.md

@@ -134,6 +134,8 @@ After calling `CPMAddPackage`, the following variables are defined in the local
 
 For using CPM.cmake projects with external package managers, such as conan or vcpkg, setting the variable [`CPM_USE_LOCAL_PACKAGES`](#options) will make CPM.cmake try to add a package through `find_package` first, and add it from source if it doesn't succeed.
 
+When using `find_package`, CPM will automatically try to locate installed packages using organization-prefixed names. For example, a package specified as `gh:org/library` will first be searched as `library`, and if not found, will be searched as `org-library`. This allows installed packages to be found using their organization-qualified names to avoid naming conflicts.
+
 In rare cases, this behaviour may be desirable by default. The function `CPMFindPackage` will try to find a local dependency via CMake's `find_package` and fallback to `CPMAddPackage`, if the dependency is not found.
 
 ## Updating CPM

cmake/CPM.cmake

@@ -197,6 +197,10 @@ function(cpm_package_name_from_git_uri URI RESULT)
         ${CMAKE_MATCH_1}
         PARENT_SCOPE
     )
+    # Also export org-prefixed variant if org can be extracted
+    if("${URI}" MATCHES "[/:]([^/:]+)/([^/:]+)(/?.git/?)?$")
+      set(${RESULT}_WITH_ORG "${CMAKE_MATCH_1}-${CMAKE_MATCH_2}" PARENT_SCOPE)
+    endif()
   else()
     unset(${RESULT} PARENT_SCOPE)
   endif()
@@ -304,7 +308,14 @@ endfunction()
 
 function(cpm_find_package NAME VERSION)
   string(REPLACE " " ";" EXTRA_ARGS "${ARGN}")
-  find_package(${NAME} ${VERSION} ${EXTRA_ARGS} QUIET)
+  find_package(${NAME} ${VERSION} ${EXTRA_ARGS} QUIET
+
+  if(NOT ${CPM_ARGS_NAME}_FOUND AND DEFINED ${CPM_ARGS_NAME}_WITH_ORG)
+    find_package(${${CPM_ARGS_NAME}_WITH_ORG} ${CPM_ARGS_VERSION} QUIET ${CPM_ARGS_FIND_PACKAGE_ARGUMENTS})
+    if(${${CPM_ARGS_NAME}_WITH_ORG}_FOUND)
+      set(${CPM_ARGS_NAME}_FOUND TRUE)
+    endif()
+  endif()
   if(${CPM_ARGS_NAME}_FOUND)
     if(DEFINED ${CPM_ARGS_NAME}_VERSION)
       set(VERSION ${${CPM_ARGS_NAME}_VERSION})