Support for showing extra info for diagstics

This was intended to show the full clang output for a given diagnostic,
including notes. But it appears that libclang does not provide this
functionality...

autoload/youcompleteme.vim

@@ -74,6 +74,9 @@ function! youcompleteme#Enable()
     inoremap <unique> <C-Space> <C-X><C-O><C-P>
   endif
 
+  " TODO: make this a nicer, customizable map
+  nnoremap <unique> <leader>d :call <sid>ShowDetailedDiagnostic()<cr>
+
   " Calling this once solves the problem of BufRead/BufEnter not triggering for
   " the first loaded file. This should be the last command executed in this
   " function!
@@ -350,6 +353,11 @@ function! youcompleteme#OmniComplete( findstart, base )
 endfunction
 
 
+function! s:ShowDetailedDiagnostic()
+  py ycm_state.ShowDetailedDiagnostic()
+endfunction
+
+
 " This is what Syntastic calls indirectly when it decides an auto-check is
 " required (currently that's on buffer save) OR when the SyntasticCheck command
 " is invoked
@@ -357,6 +365,7 @@ function! youcompleteme#CurrentFileDiagnostics()
   return pyeval( 'ycm_state.GetDiagnosticsForCurrentFile()' )
 endfunction
 
+
 " This is basic vim plugin boilerplate
 let &cpo = s:save_cpo
 unlet s:save_cpo

cpp/ycm/ClangUtils.cpp

@@ -123,6 +123,38 @@ std::vector< CompletionData > ToCompletionDataVector(
 }
 
 
+// NOTE: The passed in pointer should never be NULL!
+// TODO: move all functions that are not external into an unnamed namespace
+std::string FullDiagnosticText( CXDiagnostic cxdiagnostic )
+{
+  std::string full_text = CXStringToString( clang_formatDiagnostic(
+      cxdiagnostic,
+      clang_defaultDiagnosticDisplayOptions() ) );
+
+  // Note: clang docs say that a CXDiagnosticSet retrieved with
+  // clang_getChildDiagnostics do NOT need to be released with
+  // clang_diposeDiagnosticSet
+  CXDiagnosticSet diag_set = clang_getChildDiagnostics( cxdiagnostic );
+  if ( !diag_set )
+    return full_text;
+
+  uint num_child_diagnostics = clang_getNumDiagnosticsInSet( diag_set );
+  if ( !num_child_diagnostics )
+    return full_text;
+
+  for ( uint i = 0; i < num_child_diagnostics; ++i )
+  {
+    CXDiagnostic diagnostic = clang_getDiagnosticInSet( diag_set, i );
+    if ( !diagnostic )
+      continue;
+
+    full_text.append( FullDiagnosticText( diagnostic ) );
+  }
+
+  return full_text;
+}
+
+
 Diagnostic CXDiagnosticToDiagnostic( CXDiagnostic cxdiagnostic )
 {
   Diagnostic diagnostic;
@@ -145,9 +177,11 @@ Diagnostic CXDiagnosticToDiagnostic( CXDiagnostic cxdiagnostic )
                              &diagnostic.line_number_,
                              &diagnostic.column_number_,
                              &unused_offset );
+
   diagnostic.filename_ = CXStringToString( clang_getFileName( file ) );
   diagnostic.text_ = CXStringToString(
       clang_getDiagnosticSpelling( cxdiagnostic ) );
+  diagnostic.long_formatted_text_ = FullDiagnosticText( cxdiagnostic );
 
   clang_disposeDiagnostic( cxdiagnostic );
   return diagnostic;

cpp/ycm/Diagnostic.h

@@ -47,6 +47,8 @@ struct Diagnostic
   std::string filename_;
 
   std::string text_;
+
+  std::string long_formatted_text_;
 };
 
 } // namespace YouCompleteMe

cpp/ycm/ycm_core.cpp

@@ -54,7 +54,8 @@ BOOST_PYTHON_MODULE(ycm_core)
     .def_readonly( "column_number_", &Diagnostic::column_number_ )
     .def_readonly( "kind_", &Diagnostic::kind_ )
     .def_readonly( "filename_", &Diagnostic::filename_ )
-    .def_readonly( "text_", &Diagnostic::text_ );
+    .def_readonly( "text_", &Diagnostic::text_ )
+    .def_readonly( "long_formatted_text_", &Diagnostic::long_formatted_text_ );
 
 	class_< std::vector< Diagnostic > >( "DiagnosticVec" )
 		.def( vector_indexing_suite< std::vector< Diagnostic > >() );

python/completers/completer.py

@@ -78,6 +78,10 @@ class Completer( object ):
     return []
 
 
+  def ShowDetailedDiagnostic( self ):
+    pass
+
+
   @abc.abstractmethod
   def SupportedFiletypes( self ):
     pass

python/completers/cpp/clang_completer.py

@@ -18,6 +18,7 @@
 # along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.
 
 from completers.completer import Completer
+from collections import defaultdict
 import vim
 import vimsupport
 import ycm_core
@@ -32,7 +33,7 @@ class ClangCompleter( Completer ):
     self.completer.EnableThreading()
     self.contents_holder = []
     self.filename_holder = []
-    self.last_diagnostics = []
+    self.last_prepared_diagnostics = []
     self.parse_future = None
     self.flags = Flags()
 
@@ -127,11 +128,38 @@ class ClangCompleter( Completer ):
 
   def GetDiagnosticsForCurrentFile( self ):
     if self.DiagnosticsForCurrentFileReady():
-      self.last_diagnostics = [ DiagnosticToDict( x ) for x in
-                                self.completer.DiagnosticsForFile(
-                                  vim.current.buffer.name ) ]
+      diagnostics = self.completer.DiagnosticsForFile( vim.current.buffer.name )
+      self.diagnostic_store = DiagnosticsToDiagStructure( diagnostics )
+      self.last_prepared_diagnostics = [ DiagnosticToDict( x ) for x in
+                                         diagnostics ]
       self.parse_future = None
-    return self.last_diagnostics
+    return self.last_prepared_diagnostics
+
+
+  def ShowDetailedDiagnostic( self ):
+    current_line, current_column = vimsupport.CurrentLineAndColumn()
+
+    # CurrentLineAndColumn() numbers are 0-based, clang numbers are 1-based
+    current_line += 1
+    current_column += 1
+
+    current_file = vim.current.buffer.name
+    diagnostics = self.diagnostic_store[ current_file ][ current_line ]
+
+    if not diagnostics:
+      vimsupport.PostVimMessage( "No diagnostic for current line!" )
+      return
+
+    closest_diagnostic = None
+    distance_to_closest_diagnostic = 999
+
+    for diagnostic in diagnostics:
+      distance = abs( current_column - diagnostic.column_number_ )
+      if distance < distance_to_closest_diagnostic:
+        distance_to_closest_diagnostic = distance
+        closest_diagnostic = diagnostic
+
+    vimsupport.EchoText( closest_diagnostic.long_formatted_text_ )
 
 
   def ShouldUseNow( self, start_column ):
@@ -165,6 +193,14 @@ def DiagnosticToDict( diagnostic ):
   }
 
 
+def DiagnosticsToDiagStructure( diagnostics ):
+  structure = defaultdict(lambda : defaultdict(list))
+  for diagnostic in diagnostics:
+    structure[ diagnostic.filename_ ][ diagnostic.line_number_ ].append(
+        diagnostic )
+  return structure
+
+
 def ClangAvailableForBuffer( buffer_object ):
   filetype = vim.eval( 'getbufvar({0}, "&ft")'.format( buffer_object.number ) )
   return filetype in CLANG_FILETYPES

python/vimsupport.py

@@ -20,6 +20,7 @@
 import vim
 
 def CurrentLineAndColumn():
+  """Returns the 0-based current line."""
   # See the comment in CurrentColumn about the calculation for the line and
   # column number
   line, column = vim.current.window.cursor
@@ -28,8 +29,9 @@ def CurrentLineAndColumn():
 
 
 def CurrentColumn():
-  """Do NOT access the CurrentColumn in vim.current.line. It doesn't exist yet.
-  Only the chars before the current column exist in vim.current.line."""
+  """Returns the 0-based current column. Do NOT access the CurrentColumn in
+  vim.current.line. It doesn't exist yet.  Only the chars before the current
+  column exist in vim.current.line."""
 
   # vim's columns are 1-based while vim.current.line columns are 0-based
   # ... but vim.current.window.cursor (which returns a (line, column) tuple)
@@ -58,6 +60,10 @@ def PostVimMessage( message ):
                .format( message ) )
 
 
+def EchoText( text ):
+  vim.command( "echom '{0}'".format( text.replace( "'", r"''") ) )
+
+
 def EscapeForVim( text ):
   return text.replace( "'", "''" )
 

python/ycm.py

@@ -106,6 +106,11 @@ class YouCompleteMe( object ):
     return []
 
 
+  def ShowDetailedDiagnostic( self ):
+    if self.FiletypeCompletionEnabledForCurrentFile():
+      return self.GetFiletypeCompleterForCurrentFile().ShowDetailedDiagnostic()
+
+
   def OnCurrentIdentifierFinished( self ):
     self.identcomp.OnCurrentIdentifierFinished()