ENH: Add install(DIRECTORY) option 'OPTIONAL'

This adds the OPTIONAL option to the install(DIRECTORY) command.  It
tells the installation rule that it is not an error if the source
directory does not exist.  See issue #8394.

1 files changed, 4 insertions, 4 deletions

diff --git a/Source/cmInstallDirectoryGenerator.cxx b/Source/cmInstallDirectoryGenerator.cxx
index 110e6b6284..6f46d297f6 100644
--- a/Source/cmInstallDirectoryGenerator.cxx
+++ b/Source/cmInstallDirectoryGenerator.cxx
@@ -26,10 +26,11 @@ cmInstallDirectoryGenerator
                               const char* dir_permissions,
                               std::vector<std::string> const& configurations,
                               const char* component,
-                              const char* literal_args):
+                              const char* literal_args,
+                              bool optional):
   cmInstallGenerator(dest, configurations, component), Directories(dirs),
   FilePermissions(file_permissions), DirPermissions(dir_permissions),
-  LiteralArguments(literal_args)
+  LiteralArguments(literal_args), Optional(optional)
 {
 }
 
@@ -45,12 +46,11 @@ cmInstallDirectoryGenerator::GenerateScriptActions(std::ostream& os,
                                                    Indent const& indent)
 {
   // Write code to install the directories.
-  bool not_optional = false;
   const char* no_properties = 0;
   const char* no_rename = 0;
   this->AddInstallRule(os, cmTarget::INSTALL_DIRECTORY,
                        this->Directories,
-                       not_optional, no_properties,
+                       this->Optional, no_properties,
                        this->FilePermissions.c_str(),
                        this->DirPermissions.c_str(),
                        no_rename, this->LiteralArguments.c_str(),