cmGlobalGenerator: Add a class that represent the build command

This refactors a std::vector<std::string> into a class so that
we can extend the features to represent things such as multiple
chained commands in the future.

1 files changed, 53 insertions, 1 deletions

diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index 36d3d107e4..ca5708b373 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -41,6 +41,54 @@ class cmSourceFile;
 class cmStateDirectory;
 class cmake;
 
+namespace detail {
+inline void AppendStrs(std::vector<std::string>&)
+{
+}
+template <typename T, typename... Ts>
+inline void AppendStrs(std::vector<std::string>& command, T&& s, Ts&&... ts)
+{
+  command.emplace_back(std::forward<T>(s));
+  AppendStrs(command, std::forward<Ts>(ts)...);
+}
+
+struct GeneratedMakeCommand
+{
+  // Add each argument as a separate element to the vector
+  template <typename... T>
+  void add(T&&... args)
+  {
+    // iterate the args and append each one
+    AppendStrs(PrimaryCommand, std::forward<T>(args)...);
+  }
+
+  // Add each value in the iterators as a separate element to the vector
+  void add(std::vector<std::string>::const_iterator start,
+           std::vector<std::string>::const_iterator end)
+  {
+    PrimaryCommand.insert(PrimaryCommand.end(), start, end);
+  }
+
+  std::string printable() const
+  {
+    std::size_t size = PrimaryCommand.size();
+    for (auto&& i : PrimaryCommand) {
+      size += i.size();
+    }
+    std::string buffer;
+    buffer.reserve(size);
+    for (auto&& i : PrimaryCommand) {
+      buffer.append(i);
+      buffer.append(1, ' ');
+    }
+    return buffer;
+  }
+
+  std::vector<std::string> PrimaryCommand;
+  bool RequiresOutputForward = false;
+};
+}
+
 /** \class cmGlobalGenerator
  * \brief Responsible for overseeing the generation process for the entire tree
  *
@@ -182,8 +230,12 @@ public:
   virtual bool Open(const std::string& bindir, const std::string& projectName,
                     bool dryRun);
 
+  struct GeneratedMakeCommand final : public detail::GeneratedMakeCommand
+  {
+  };
+
   virtual void GenerateBuildCommand(
-    std::vector<std::string>& makeCommand, const std::string& makeProgram,
+    GeneratedMakeCommand& makeCommand, const std::string& makeProgram,
     const std::string& projectName, const std::string& projectDir,
     const std::string& targetName, const std::string& config, bool fast,
     int jobs, bool verbose,