Merge topic 'ImprovedCOMPONENTSSupportInFindPackage2'

6d100f9 find_package: Test rejection of required+optional components
d81d83c add macro check_required_components() to configure_package_config_file()
b15c0b4 FPHSA(): add HANDLE_COMPONENTS option
34108cd find_package: add documentation for OPTIONAL_COMPONENTS
cdabde8 FPHSA(): add missing "]" to documentation
f2e0a18 find_package: add OPTIONAL_COMPONENTS keyword

1 files changed, 48 insertions, 9 deletions

diff --git a/Source/cmFindPackageCommand.cxx b/Source/cmFindPackageCommand.cxx
index 3541ca3..ef16ce8 100644
--- a/Source/cmFindPackageCommand.cxx
+++ b/Source/cmFindPackageCommand.cxx
@@ -90,6 +90,7 @@ void cmFindPackageCommand::GenerateDocumentation()
   this->CommandDocumentation =
     "  find_package(<package> [version] [EXACT] [QUIET] [MODULE]\n"
     "               [[REQUIRED|COMPONENTS] [components...]]\n"
+    "               [OPTIONAL_COMPONENTS components...]\n"
     "               [NO_POLICY_SCOPE])\n"
     "Finds and loads settings from an external project.  "
     "<package>_FOUND will be set to indicate whether the package was found.  "
@@ -98,10 +99,14 @@ void cmFindPackageCommand::GenerateDocumentation()
     "The QUIET option disables messages if the package cannot be found.  "
     "The MODULE option disables the second signature documented below.  "
     "The REQUIRED option stops processing with an error message if the "
-    "package cannot be found.  "
-    "A package-specific list of components may be listed after the "
-    "REQUIRED option or after the COMPONENTS option if no REQUIRED "
-    "option is given.  "
+    "package cannot be found."
+    "\n"
+    "A package-specific list of required components may be listed after the "
+    "COMPONENTS option or directly after the REQUIRED option.  "
+    "Additional optional components may be listed after OPTIONAL_COMPONENTS.  "
+    "Available components and their influence on whether a package is "
+    "considered to be found are defined by the target package."
+    "\n"
     "The [version] argument requests a version with which the package found "
     "should be compatible (format is major[.minor[.patch[.tweak]]]).  "
     "The EXACT option requests that the version be matched exactly.  "
@@ -410,6 +415,8 @@ bool cmFindPackageCommand
   this->Name = args[0];
   std::string components;
   const char* components_sep = "";
+  std::set<std::string> requiredComponents;
+  std::set<std::string> optionalComponents;
 
   // Check ancient compatibility.
   this->Compatibility_1_6 =
@@ -420,8 +427,8 @@ bool cmFindPackageCommand
   this->SearchPathSuffixes.push_back("");
 
   // Parse the arguments.
-  enum Doing { DoingNone, DoingComponents, DoingNames, DoingPaths,
-               DoingPathSuffixes, DoingConfigs, DoingHints };
+  enum Doing { DoingNone, DoingComponents, DoingOptionalComponents, DoingNames,
+               DoingPaths, DoingPathSuffixes, DoingConfigs, DoingHints };
   Doing doing = DoingNone;
   cmsys::RegularExpression version("^[0-9.]+$");
   bool haveVersion = false;
@@ -465,6 +472,11 @@ bool cmFindPackageCommand
       this->Compatibility_1_6 = false;
       doing = DoingComponents;
       }
+    else if(args[i] == "OPTIONAL_COMPONENTS")
+      {
+      this->Compatibility_1_6 = false;
+      doing = DoingOptionalComponents;
+      }
     else if(args[i] == "NAMES")
       {
       configArgs.insert(i);
@@ -528,12 +540,23 @@ bool cmFindPackageCommand
       this->Compatibility_1_6 = false;
       doing = DoingNone;
       }
-    else if(doing == DoingComponents)
+    else if((doing == DoingComponents) || (doing == DoingOptionalComponents))
       {
-      // Set a variable telling the find script this component
+      // Set a variable telling the find script whether this component
       // is required.
+      const char* isRequired = "1";
+      if (doing == DoingOptionalComponents)
+        {
+        isRequired = "0";
+        optionalComponents.insert(args[i]);
+        }
+      else
+        {
+        requiredComponents.insert(args[i]);
+        }
+
       std::string req_var = this->Name + "_FIND_REQUIRED_" + args[i];
-      this->AddFindDefinition(req_var.c_str(), "1");
+      this->AddFindDefinition(req_var.c_str(), isRequired);
 
       // Append to the list of required components.
       components += components_sep;
@@ -584,6 +607,22 @@ bool cmFindPackageCommand
       }
     }
 
+  std::vector<std::string> doubledComponents;
+  std::set_intersection(requiredComponents.begin(), requiredComponents.end(),
+                        optionalComponents.begin(), optionalComponents.end(),
+                        std::back_inserter(doubledComponents));
+  if(!doubledComponents.empty())
+    {
+    cmOStringStream e;
+    e << "called with components that are both required and optional:\n";
+    for(unsigned int i=0; i<doubledComponents.size(); ++i)
+      {
+      e << "  " << doubledComponents[i] << "\n";
+      }
+    this->SetError(e.str().c_str());
+    return false;
+    }
+
   // Maybe choose one mode exclusively.
   this->UseFindModules = configArgs.empty();
   this->UseConfigFiles = moduleArgs.empty();