Added back in reference.

src/renderer/renderer.rs

@@ -1,8 +1,10 @@
 use crate::parser::template;
 use crate::parser::Body;
 use crate::parser::DustTag;
+use crate::parser::Filter;
 use crate::parser::PartialNameElement;
 use crate::parser::Path;
+use crate::parser::Special;
 use crate::parser::Template;
 use crate::parser::TemplateElement;
 use crate::renderer::breadcrumb_tree::BreadcrumbTree;
@@ -11,6 +13,7 @@ use crate::renderer::context_element::ContextElement;
 use crate::renderer::context_element::IntoContextElement;
 use crate::renderer::errors::CompileError;
 use crate::renderer::errors::RenderError;
+use crate::renderer::errors::WalkError;
 use crate::renderer::inline_partial_tree::extract_inline_partials;
 use crate::renderer::inline_partial_tree::InlinePartialTreeElement;
 use crate::renderer::tree_walking::walk_path;
@@ -132,6 +135,32 @@ impl<'a> DustRenderer<'a> {
         blocks: &'a BlockContext<'a>,
     ) -> Result<String, RenderError> {
         match tag {
+            DustTag::DTComment(_comment) => (),
+            DustTag::DTSpecial(special) => {
+                return Ok(match special {
+                    Special::Space => " ",
+                    Special::NewLine => "\n",
+                    Special::CarriageReturn => "\r",
+                    Special::LeftCurlyBrace => "{",
+                    Special::RightCurlyBrace => "}",
+                }
+                .to_owned())
+            }
+            DustTag::DTLiteralStringBlock(literal) => return Ok((*literal).to_owned()),
+            DustTag::DTReference(reference) => {
+                let val = walk_path(breadcrumbs, &reference.path.keys)
+                    .map(|ice| ice.into_context_element(self, breadcrumbs));
+                match val {
+                    Err(WalkError::CantWalk) => return Ok("".to_owned()),
+                    Ok(final_val) => {
+                        return if final_val.is_truthy() {
+                            final_val.render(&Self::preprocess_filters(&reference.filters))
+                        } else {
+                            Ok("".to_owned())
+                        };
+                    }
+                }
+            }
             _ => panic!("Unsupported tag"),
         }
         Ok("".to_owned())
@@ -281,6 +310,21 @@ impl<'a> DustRenderer<'a> {
             }
         }
     }
+
+    fn preprocess_filters(filters: &Vec<Filter>) -> Vec<Filter> {
+        let mut final_filters: Vec<Filter> = filters
+            .into_iter()
+            .filter(|f| f != &&Filter::DisableHtmlEncode)
+            .map(|f| f.clone())
+            .collect();
+
+        // If the user has not specified any escaping filter (|s or
+        // |h), automatically add an html escape filter
+        if !filters.iter().any(|f| f == &Filter::DisableHtmlEncode) {
+            final_filters.push(Filter::HtmlEncode);
+        }
+        final_filters
+    }
 }
 
 struct BlockContext<'a> {