ENH: Allow custom sources in custom targets

This adds a SOURCES option to ADD_CUSTOM_TARGET, enabling users to
specify extra sources for inclusion in the target.  Such sources may not
build, but will show up in the IDE project files for convenient editing.
See issue #5848.

Source/cmAddCustomTargetCommand.cxx

@@ -55,6 +55,7 @@ bool cmAddCustomTargetCommand
   bool verbatim = false;
   std::string comment_buffer;
   const char* comment = 0;
+  std::vector<std::string> sources;
 
   // Keep track of parser state.
   enum tdoing {
@@ -62,6 +63,7 @@ bool cmAddCustomTargetCommand
     doing_depends,
     doing_working_directory,
     doing_comment,
+    doing_source,
     doing_verbatim
   };
   tdoing doing = doing_command;
@@ -111,6 +113,10 @@ bool cmAddCustomTargetCommand
         currentLine.clear();
         }
       }
+    else if(copy == "SOURCES")
+      {
+      doing = doing_source;
+      }
     else
       {
       switch (doing)
@@ -128,6 +134,9 @@ bool cmAddCustomTargetCommand
            comment_buffer = copy;
            comment = comment_buffer.c_str();
            break;
+        case doing_source:
+          sources.push_back(copy);
+          break;
         default:
           this->SetError("Wrong syntax. Unknown type of argument.");
           return false;
@@ -164,9 +173,13 @@ bool cmAddCustomTargetCommand
 
   // Add the utility target to the makefile.
   bool escapeOldStyle = !verbatim;
-  this->Makefile->AddUtilityCommand(args[0].c_str(), excludeFromAll,
-                                    working_directory.c_str(), depends,
-                                    commandLines, escapeOldStyle, comment);
+  cmTarget* target =
+    this->Makefile->AddUtilityCommand(args[0].c_str(), excludeFromAll,
+                                      working_directory.c_str(), depends,
+                                      commandLines, escapeOldStyle, comment);
+
+  // Add additional user-specified source files to the target.
+  target->AddSources(sources);
 
   return true;
 }

Source/cmAddCustomTargetCommand.h

@@ -68,7 +68,8 @@ public:
       "                    [COMMAND command2 [args2...] ...]\n"
       "                    [DEPENDS depend depend depend ... ]\n"
       "                    [WORKING_DIRECTORY dir]\n"
-      "                    [COMMENT comment] [VERBATIM])\n"
+      "                    [COMMENT comment] [VERBATIM]\n"
+      "                    [SOURCES src1 [src2...]])\n"
       "Adds a target with the given name that executes the given commands. "
       "The target has no output file and is ALWAYS CONSIDERED OUT OF DATE "
       "even if the commands try to create a file with the name of the "
@@ -94,7 +95,13 @@ public:
       "Use of VERBATIM is recommended as it enables correct behavior. "
       "When VERBATIM is not given the behavior is platform specific. "
       "In the future VERBATIM may be enabled by default. The only reason "
-      "it is an option is to preserve compatibility with older CMake code.";
+      "it is an option is to preserve compatibility with older CMake code."
+      "\n"
+      "The SOURCES option specifies additional source files to be included "
+      "in the custom target.  "
+      "Specified source files will be added to IDE project files for "
+      "convenience in editing even if they have not build rules."
+      ;
     }
   
   cmTypeMacro(cmAddCustomTargetCommand, cmCommand);

Tests/CustomCommand/CMakeLists.txt

@@ -100,6 +100,7 @@ ADD_CUSTOM_TARGET(TDocument ALL
                                    ${PROJECT_BINARY_DIR}/doc2.h
   DEPENDS ${PROJECT_BINARY_DIR}/doc1.h doc1.txt
   COMMENT "Running top-level TDocument commands"
+  SOURCES doc1.tex
   )
 
 # Setup a pre- and post-build pair that will fail if not run in the