cmake: add --trace-expand option

The --trace option is helpful, but sometimes, what you're looking for is
deep under many layers of function calls and figuring out what instance
of the function call you're looking at is tedious to determine (usually
involving patching and message()). Instead, add a --trace-expand option
to trace while expanding commands into what CMake actually sees.

1 files changed, 8 insertions, 0 deletions

diff --git a/Source/cmake.cxx b/Source/cmake.cxx
index 7bf3832..6abdbed 100644
--- a/Source/cmake.cxx
+++ b/Source/cmake.cxx
@@ -121,6 +121,7 @@ void cmWarnUnusedCliWarning(const std::string& variable,
 cmake::cmake()
 {
   this->Trace = false;
+  this->TraceExpand = false;
   this->WarnUninitialized = false;
   this->WarnUnused = false;
   this->WarnUnusedCli = true;
@@ -617,10 +618,17 @@ void cmake::SetArgs(const std::vector<std::string>& args,
       std::cout << "Running with debug output on.\n";
       this->SetDebugOutputOn(true);
       }
+    else if(arg.find("--trace-expand",0) == 0)
+      {
+      std::cout << "Running with expanded trace output on.\n";
+      this->SetTrace(true);
+      this->SetTraceExpand(true);
+      }
     else if(arg.find("--trace",0) == 0)
       {
       std::cout << "Running with trace output on.\n";
       this->SetTrace(true);
+      this->SetTraceExpand(false);
       }
     else if(arg.find("--warn-uninitialized",0) == 0)
       {