cmMessenger: Adopt backtrace printing functions

Move backtrace printing functions from `cmListFileBacktrace` over to
`cmMessenger`, their primary caller.  Thread `cmMessenger` instances
through APIs needed to update other call sites.

1 files changed, 56 insertions, 2 deletions

diff --git a/Source/cmMessenger.cxx b/Source/cmMessenger.cxx
index 2eead6b..52c9dd0 100644
--- a/Source/cmMessenger.cxx
+++ b/Source/cmMessenger.cxx
@@ -4,6 +4,8 @@
 
 #include "cmDocumentationFormatter.h"
 #include "cmMessageMetadata.h"
+#include "cmState.h"
+#include "cmStateSnapshot.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
 
@@ -151,6 +153,42 @@ static void displayMessage(MessageType t, std::ostringstream& msg)
   }
 }
 
+namespace {
+void PrintCallStack(std::ostream& out, cmListFileBacktrace bt)
+{
+  // The call stack exists only if we have at least two calls on top
+  // of the bottom.
+  if (bt.Empty()) {
+    return;
+  }
+  bt = bt.Pop();
+  if (bt.Empty()) {
+    return;
+  }
+
+  bool first = true;
+  cmStateSnapshot bottom = bt.GetBottom();
+  for (; !bt.Empty(); bt = bt.Pop()) {
+    cmListFileContext lfc = bt.Top();
+    if (lfc.Name.empty() &&
+        lfc.Line != cmListFileContext::DeferPlaceholderLine) {
+      // Skip this whole-file scope.  When we get here we already will
+      // have printed a more-specific context within the file.
+      continue;
+    }
+    if (first) {
+      first = false;
+      out << "Call Stack (most recent call first):\n";
+    }
+    if (bottom.GetState()->GetProjectKind() == cmState::ProjectKind::Normal) {
+      lfc.FilePath = cmSystemTools::RelativeIfUnder(
+        bottom.GetState()->GetSourceDirectory(), lfc.FilePath);
+    }
+    out << "  " << lfc << "\n";
+  }
+}
+}
+
 void cmMessenger::IssueMessage(MessageType t, const std::string& text,
                                const cmListFileBacktrace& backtrace) const
 {
@@ -176,12 +214,28 @@ void cmMessenger::DisplayMessage(MessageType t, const std::string& text,
   }
 
   // Add the immediate context.
-  backtrace.PrintTitle(msg);
+  this->PrintBacktraceTitle(msg, backtrace);
 
   printMessageText(msg, text);
 
   // Add the rest of the context.
-  backtrace.PrintCallStack(msg);
+  PrintCallStack(msg, backtrace);
 
   displayMessage(t, msg);
 }
+
+void cmMessenger::PrintBacktraceTitle(std::ostream& out,
+                                      cmListFileBacktrace const& bt) const
+{
+  // The title exists only if we have a call on top of the bottom.
+  if (bt.Empty()) {
+    return;
+  }
+  cmListFileContext lfc = bt.Top();
+  cmStateSnapshot bottom = bt.GetBottom();
+  if (bottom.GetState()->GetProjectKind() == cmState::ProjectKind::Normal) {
+    lfc.FilePath = cmSystemTools::RelativeIfUnder(
+      bottom.GetState()->GetSourceDirectory(), lfc.FilePath);
+  }
+  out << (lfc.Line ? " at " : " in ") << lfc;
+}