Support column-based breakpoints in the VM and Observatory.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 8574 matching lines @@
                                intptr_t col_offset) const {
   ASSERT(line_offset >= 0);
   ASSERT(col_offset >= 0);
   StoreNonPointer(&raw_ptr()->line_offset_, line_offset);
   StoreNonPointer(&raw_ptr()->col_offset_, col_offset);
 }
 
 
 void Script::GetTokenLocation(intptr_t token_pos,
                               intptr_t* line,
-                              intptr_t* column) const {
+                              intptr_t* column,
+                              intptr_t* token_len) const {
   ASSERT(line != NULL);
   const TokenStream& tkns = TokenStream::Handle(tokens());
   if (column == NULL) {
     TokenStream::Iterator tkit(tkns, 0, TokenStream::Iterator::kAllTokens);
     intptr_t cur_line = line_offset() + 1;
     while (tkit.CurrentPosition() < token_pos &&
            tkit.CurrentTokenKind() != Token::kEOS) {
       if (tkit.CurrentTokenKind() == Token::kNEWLINE) {
         cur_line++;
       }
       tkit.Advance();
     }
     *line = cur_line;
   } else {
     const String& src = String::Handle(Source());
     intptr_t src_pos = tkns.ComputeSourcePosition(token_pos);
     Scanner scanner(src, Symbols::Empty());
     scanner.ScanTo(src_pos);
     intptr_t relative_line = scanner.CurrentPosition().line;
     *line = relative_line + line_offset();
     *column = scanner.CurrentPosition().column;
+    if (token_len != NULL) {
+      if (scanner.current_token().literal != NULL) {
+        *token_len = scanner.current_token().literal->Length();
+      } else {
+        *token_len = 1;

[rmacnak, 2015/09/03 00:55:19]

Maybe otherwise keyword length?

[turnidge, 2015/09/04 18:05:29]

My hope was that the literal pointed to the keyword but perhaps this was wrong. 
(See scanner.cc:319)

+      }
+    }
     // On the first line of the script we must add the column offset.
     if (relative_line == 1) {
       *column += col_offset();
     }
   }
 }
 
 
 void Script::TokenRangeAtLine(intptr_t line_number,
                               intptr_t* first_token_index,
@@ skipping 12879 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart