add --xpretty flowgraph,unlabelled variant.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/librustc/middle/cfg/graphviz.rs b/src/librustc/middle/cfg/graphviz.rs
index f4db2b6e61d..3d8348e8f5a 100644
--- a/src/librustc/middle/cfg/graphviz.rs
+++ b/src/librustc/middle/cfg/graphviz.rs
@@ -28,6 +28,8 @@ pub struct LabelledCFG<'a, 'ast: 'a> {
     pub ast_map: &'a ast_map::Map<'ast>,
     pub cfg: &'a cfg::CFG,
     pub name: String,
+    /// `labelled_edges` controls whether we emit labels on the edges
+    pub labelled_edges: bool,
 }
 
 fn replace_newline_with_backslash_l(s: String) -> String {
@@ -75,6 +77,9 @@ impl<'a, 'ast> dot::Labeller<'a, Node<'a>, Edge<'a>> for LabelledCFG<'a, 'ast> {
 
     fn edge_label(&self, e: &Edge<'a>) -> dot::LabelText<'a> {
         let mut label = String::new();
+        if !self.labelled_edges {
+            return dot::LabelText::EscStr(label.into_cow());
+        }
         let mut put_one = false;
         for (i, &node_id) in e.data.exiting_scopes.iter().enumerate() {
             if put_one {