From 5efa650b67d98568a77785f83685f53e11893643 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sat, 11 Apr 2020 22:19:54 -0400
Subject: [PATCH] Switching to a combined ContextElement trait for Walkable and
 Renderable

---
 src/renderer/mod.rs      |  1 +
 src/renderer/renderer.rs | 44 ++++++++++++++++++++++++++++++++--------
 src/renderer/walkable.rs |  6 +++---
 3 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs
index 81b7e79..c80f1a5 100644
--- a/src/renderer/mod.rs
+++ b/src/renderer/mod.rs
@@ -9,4 +9,5 @@ pub use renderable::Renderable;
 pub use renderer::compile_template;
 pub use renderer::CompiledTemplate;
 pub use renderer::DustRenderer;
+pub use walkable::ContextElement;
 pub use walkable::Walkable;
diff --git a/src/renderer/renderer.rs b/src/renderer/renderer.rs
index fbb79dd..88e2986 100644
--- a/src/renderer/renderer.rs
+++ b/src/renderer/renderer.rs
@@ -111,9 +111,32 @@ impl<'a> DustRenderer<'a> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::renderer::walkable::ContextElement;
 
-    impl<I: Walkable> Walkable for HashMap<&str, I> {
-        fn walk(&self, segment: &str) -> &dyn Walkable {
+    impl ContextElement for u32 {}
+    impl ContextElement for &str {}
+    impl<I: ContextElement> ContextElement for HashMap<&str, I> {}
+
+    impl Renderable for u32 {
+        fn render(&self) -> std::string::String {
+            self.to_string()
+        }
+    }
+
+    impl Renderable for &str {
+        fn render(&self) -> std::string::String {
+            self.to_string()
+        }
+    }
+
+    impl<I: ContextElement> Renderable for HashMap<&str, I> {
+        fn render(&self) -> std::string::String {
+            panic!("Attempted to render a hashmap");
+        }
+    }
+
+    impl<I: ContextElement> Walkable for HashMap<&str, I> {
+        fn walk(&self, segment: &str) -> &dyn ContextElement {
             self.get(segment).unwrap()
         }
 
@@ -123,7 +146,7 @@ mod tests {
     }
 
     impl Walkable for &str {
-        fn walk(&self, segment: &str) -> &dyn Walkable {
+        fn walk(&self, segment: &str) -> &dyn ContextElement {
             panic!("Tried to walk down a str");
         }
 
@@ -133,7 +156,7 @@ mod tests {
     }
 
     impl Walkable for u32 {
-        fn walk(&self, segment: &str) -> &dyn Walkable {
+        fn walk(&self, segment: &str) -> &dyn ContextElement {
             panic!("Tried to walk down a str");
         }
 
@@ -142,7 +165,10 @@ mod tests {
         }
     }
 
-    fn do_the_walk<'a>(context: &'a dyn Walkable, path: &Vec<&str>) -> &'a dyn Walkable {
+    fn do_the_walk<'a>(
+        context: &'a dyn ContextElement,
+        path: &Vec<&str>,
+    ) -> &'a dyn ContextElement {
         let mut output = context;
 
         for elem in path.iter() {
@@ -171,11 +197,11 @@ mod tests {
         .iter()
         .cloned()
         .collect();
-        assert_eq!(do_the_walk(&context, &vec!["cat"]).val(), "kitty");
-        // assert_eq!(do_the_walk(&number_context, &vec!["tiger"]), &3);
+        assert_eq!(do_the_walk(&context, &vec!["cat"]).render(), "kitty");
+        assert_eq!(do_the_walk(&number_context, &vec!["tiger"]).render(), "3");
         // assert_eq!(
-        //     do_the_walk(&deep_context, &vec!["tiger"]),
-        //     &[("food", "people")].iter().cloned().collect()
+        //     do_the_walk(&deep_context, &vec!["tiger", "food"]).render(),
+        //     "people"
         // );
     }
 }
diff --git a/src/renderer/walkable.rs b/src/renderer/walkable.rs
index e8bf09f..22b7426 100644
--- a/src/renderer/walkable.rs
+++ b/src/renderer/walkable.rs
@@ -1,9 +1,9 @@
 use super::renderable::Renderable;
 
-pub trait Walkable {
-    // type Output: Walkable;
+pub trait ContextElement: Walkable + Renderable {}
 
-    fn walk(&self, segment: &str) -> &dyn Walkable;
+pub trait Walkable {
+    fn walk(&self, segment: &str) -> &dyn ContextElement;
 
     fn val(&self) -> String;
 }