Add automatic variable CMAKE_CURRENT_LIST_DIR(dir of CMAKE_CURRENT_LIST_FILE)

Comes with a simple test and docs.

Alex

Source/cmDocumentVariables.cxx

@@ -77,6 +77,25 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      " processed by cmake.", false,
      "Variables that Provide Information");
 
+  cm->DefineProperty
+    ("CMAKE_CURRENT_LIST_DIR", cmProperty::VARIABLE,
+     "Full directory of the listfile currently being processed.",
+     "As CMake processes the listfiles in your project this "
+     "variable will always be set to the directory where the listfile which "
+     "is currently being processed (CMAKE_CURRENT_LIST_FILE) is located.  "
+     "The value has dynamic scope.  "
+     "When CMake starts processing commands in a source file "
+     "it sets this variable to the directory where this file is located.  "
+     "When CMake finishes processing commands from the file it "
+     "restores the previous value.  "
+     "Therefore the value of the variable inside a macro or "
+     "function is the directory of the file invoking the bottom-most entry on "
+     "the call stack, not the directory of the file containing the macro or "
+     "function definition."
+     "\n"
+     "See also CMAKE_CURRENT_LIST_FILE.",false,
+     "Variables that Provide Information");
+
   cm->DefineProperty
     ("CMAKE_BUILD_TOOL", cmProperty::VARIABLE,
      "Tool used for the actual build process.",

Source/cmMakefile.cxx

@@ -610,6 +610,8 @@ bool cmMakefile::ReadListFile(const char* filename_in,
     }
 
   this->AddDefinition("CMAKE_CURRENT_LIST_FILE", filenametoread);
+  this->AddDefinition("CMAKE_CURRENT_LIST_DIR",
+                       cmSystemTools::GetFilenamePath(filenametoread).c_str());
 
   // try to see if the list file is the top most
   // list file for a project, and if it is, then it
@@ -643,6 +645,8 @@ bool cmMakefile::ReadListFile(const char* filename_in,
       }
     this->AddDefinition("CMAKE_PARENT_LIST_FILE", currentParentFile.c_str());
     this->AddDefinition("CMAKE_CURRENT_LIST_FILE", currentFile.c_str());
+    this->AddDefinition("CMAKE_CURRENT_LIST_DIR",
+                        cmSystemTools::GetFilenamePath(currentFile).c_str());
     return false;
     }
   // add this list file to the list of dependencies
@@ -683,6 +687,8 @@ bool cmMakefile::ReadListFile(const char* filename_in,
 
   this->AddDefinition("CMAKE_PARENT_LIST_FILE", currentParentFile.c_str());
   this->AddDefinition("CMAKE_CURRENT_LIST_FILE", currentFile.c_str());
+  this->AddDefinition("CMAKE_CURRENT_LIST_DIR",
+                      cmSystemTools::GetFilenamePath(currentFile).c_str());
 
   // pop the listfile off the stack
   this->ListFileStack.pop_back();

Tests/CMakeTests/IncludeTest.cmake.in

@@ -35,3 +35,7 @@ if(NOT "${fileOne}"   STREQUAL "${fileTwo}")
    message(FATAL_ERROR "Wrong CMake.cmake was included: \"${fileOne}\" expected \"${fileTwo}\"")
 endif(NOT "${fileOne}"   STREQUAL "${fileTwo}")
 
+# Check that CMAKE_CURRENT_LIST_DIR is working:
+# Needs to be a file in the build tree, which is correct cmake script
+# but doesn't do a lot, if possible only set() commands:
+include(${CMAKE_CURRENT_LIST_DIR}/../../CTestCustom.cmake)