Allow any ID string

According to the grammar of The DOT Language[1], an ID can be given in
one of four possible formats. Where the most permissive format is any
string quoted within double quotes. For generated output to be valid,
the ID strings better use that format. Since dotavious does not, and
should not, enforce that the ID only contains characters from any of the
more limited forms.

[1]: https://www.graphviz.org/doc/info/lang.html

1 files changed, 9 insertions, 5 deletions

diff --git a/src/dot.rs b/src/dot.rs
index f154dc9..c211bdb 100644
--- a/src/dot.rs
+++ b/src/dot.rs
@@ -53,7 +53,7 @@ impl<'a> Dot<'a> {
         write!(w, "{}{}", strict, &graph.graph_type())?;
 
         if let Some(id) = &graph.id {
-            write!(w, " {}", id)?;
+            write!(w, r#" "{}""#, escape_doublequotes(id))?;
         }
 
         writeln!(w, " {{")?;
@@ -185,11 +185,11 @@ impl<'a> Dot<'a> {
 
         write!(
             w,
-            "{}{} {} {}",
+            r#"{}"{}" {} "{}""#,
             get_indentation(indentation_level),
-            edge_source,
+            escape_doublequotes(&edge_source),
             edge_op,
-            edge_target
+            escape_doublequotes(&edge_source)
         )?;
         write!(w, "{}", fmt_attributes(&edge.attributes))?;
         writeln!(w, ";")
@@ -638,7 +638,7 @@ impl<'a> Node<'a> {
 
 impl<'a> DotString<'a> for Node<'a> {
     fn dot_string(&self) -> Cow<'a, str> {
-        let mut dot_string = format!("{}", &self.id);
+        let mut dot_string = format!(r#""{}""#, escape_doublequotes(&self.id));
         dot_string.push_str(fmt_attributes(&self.attributes).as_str());
         dot_string.push_str(";");
         dot_string.into()
@@ -965,3 +965,7 @@ impl<'a> EdgeAttributeStatementBuilder<'a> {
 fn get_indentation(indentation_level: usize) -> String {
     INDENT.repeat(indentation_level)
 }
+
+fn escape_doublequotes(val: &String) -> String {
+    val.chars().map(|c| if c == '"' { format!("\\{}", c) } else { format!("{}", c)}).collect()
+}