Add support for generating the QtCreator projects from GN.

tools/gn/command_gen.cc

Index: tools/gn/command_gen.cc
diff --git a/tools/gn/command_gen.cc b/tools/gn/command_gen.cc
index fee3f1a31f836c7843eac42afdeb918722c43413..b0f84e5ff49d92909229b4596e90aa2df62e55d0 100644
--- a/tools/gn/command_gen.cc
+++ b/tools/gn/command_gen.cc
@@ -13,6 +13,7 @@
 #include "tools/gn/eclipse_writer.h"
 #include "tools/gn/ninja_target_writer.h"
 #include "tools/gn/ninja_writer.h"
+#include "tools/gn/qt_creator_writer.h"
 #include "tools/gn/runtime_deps.h"
 #include "tools/gn/scheduler.h"
 #include "tools/gn/setup.h"
@@ -29,9 +30,11 @@ const char kSwitchCheck[] = "check";
 const char kSwitchFilters[] = "filters";
 const char kSwitchIde[] = "ide";
 const char kSwitchIdeValueEclipse[] = "eclipse";
+const char kSwitchIdeValueQtCreator[] = "qtcreator";
 const char kSwitchIdeValueVs[] = "vs";
 const char kSwitchIdeValueVs2013[] = "vs2013";
 const char kSwitchIdeValueVs2015[] = "vs2015";
+const char kSwitchRootProjectTarget[] = "root-project-target";
 const char kSwitchSln[] = "sln";
 
 // Called on worker thread to write the ninja file.
@@ -188,6 +191,18 @@ bool RunIdeWriter(const std::string& ide,
                    "ms\n");
     }
     return res;
+  } else if (ide == kSwitchIdeValueQtCreator) {
+    std::string root_target;
+    if (command_line->HasSwitch(kSwitchRootProjectTarget))
+      root_target = command_line->GetSwitchValueASCII(kSwitchRootProjectTarget);
+    bool res = QtCreatorWriter::RunAndWriteFile(build_settings, builder, err,
+                                                root_target);
+    if (res && !command_line->HasSwitch(switches::kQuiet)) {
+      OutputString("Generating QtCreator project took " +
+                   base::Int64ToString(timer.Elapsed().InMilliseconds()) +
+                   "ms\n");
+    }
+    return res;
   }
 
   *err = Err(Location(), "Unknown IDE: " + ide);
@@ -225,6 +240,7 @@ const char kGen_Help[] =
     "             (default Visual Studio version: 2015)\n"
     "      \"vs2013\" - Visual Studio 2013 project/solution files.\n"
     "      \"vs2015\" - Visual Studio 2015 project/solution files.\n"
+    "      \"qtcreator\" - QtCreator project directory."

[brucedawson, 2016/05/09 18:56:49]

This should say "QtCreator project file.s" not "project directory." Also, needs
a terminating \n.

[Krzysztof Olczyk, 2016/05/10 08:11:18]

Done

     "\n"
     "  --sln=<file_name>\n"
     "      Override default sln file name (\"all\"). Solution file is written\n"
@@ -235,6 +251,10 @@ const char kGen_Help[] =
     "      of generated projects (see \"gn help label_pattern\"). Only\n"
     "      matching targets will be included to the solution. Only for Visual\n"
     "      Studio.\n"
+    "  --root-target=<target_name>\n"
+    "      Name of the root target for which the project will be generated\n"
+    "      to contain files of it and its dependencies. Omitting it traverses\n"
+    "      the whole build graph. Only for QtCreator.\n"
     "\n"
     "Eclipse IDE Support\n"
     "\n"