Merge branch 'combined_walk_path' into render

src/renderer/parameters_context.rs

@@ -2,7 +2,7 @@ use crate::parser::KVPair;
 use crate::parser::{Filter, OwnedLiteral, RValue};
 use crate::renderer::context_element::CompareContextElement;
 use crate::renderer::context_element::ContextElement;
-use crate::renderer::walking::owned_walk_path;
+use crate::renderer::walking::walk_path;
 use crate::renderer::Loopable;
 use crate::renderer::RenderError;
 use crate::renderer::Renderable;
@@ -89,7 +89,7 @@ impl Walkable for ParametersContext {
     fn walk(&self, segment: &str) -> Result<&dyn ContextElement, WalkError> {
         let rval = self.params.get(segment).ok_or(WalkError::CantWalk)?;
         match rval {
-            OwnedRValue::RVPath(path) => owned_walk_path(&self.breadcrumbs, &path.keys),
+            OwnedRValue::RVPath(path) => walk_path(&self.breadcrumbs, &path.keys),
             OwnedRValue::RVLiteral(literal) => Ok(literal),
         }
     }

src/renderer/renderer.rs

@@ -489,7 +489,7 @@ impl<'a> DustRenderer<'a> {
     }
 
     fn get_rval<'b>(
-        breadcrumbs: &Vec<&'b dyn ContextElement>,
+        breadcrumbs: &'b Vec<&'b dyn ContextElement>,
         param_map: &HashMap<&str, &'b RValue<'b>>,
         key: &str,
     ) -> Option<Result<&'b dyn ContextElement, WalkError>> {

src/renderer/walking.rs

@@ -1,5 +1,6 @@
 use crate::renderer::context_element::ContextElement;
 use crate::renderer::WalkError;
+use std::borrow::Borrow;
 
 enum WalkResult<'a> {
     NoWalk,
@@ -7,18 +8,19 @@ enum WalkResult<'a> {
     FullyWalked(&'a dyn ContextElement),
 }
 
-fn walk_path_from_single_level<'a>(
-    context: &'a dyn ContextElement,
-    path: &[&str],
-) -> WalkResult<'a> {
+fn walk_path_from_single_level<'a, P, C>(context: &'a C, path: &[P]) -> WalkResult<'a>
+where
+    P: Borrow<str>,
+    C: Borrow<dyn ContextElement + 'a>,
+{
     if path.is_empty() {
-        return WalkResult::FullyWalked(context);
+        return WalkResult::FullyWalked(context.borrow());
     }
 
     let mut walk_failure = WalkResult::NoWalk;
-    let mut output = context;
+    let mut output = context.borrow();
     for elem in path.iter() {
-        match output.walk(elem) {
+        match output.borrow().walk(elem.borrow()) {
             Err(WalkError::CantWalk { .. }) => {
                 return walk_failure;
             }
@@ -32,63 +34,31 @@ fn walk_path_from_single_level<'a>(
     WalkResult::FullyWalked(output)
 }
 
-pub fn walk_path<'a>(
-    breadcrumbs: &Vec<&'a dyn ContextElement>,
-    path: &'a Vec<&str>,
-) -> Result<&'a dyn ContextElement, WalkError> {
-    if path.is_empty() {
-        return Ok(*breadcrumbs
-            .last()
-            .expect("Breadcrumbs should never be empty"));
-    }
-    if *path.first().expect("Already proved path is not empty") == "." {
-        return match walk_path_from_single_level(
-            *breadcrumbs
-                .last()
-                .expect("Breadcrumbs should never be empty"),
-            &path[1..],
-        ) {
-            // If no walking was done at all or we partially walked
-            // then stop trying to find anything because '.' restricts
-            // us to the current scope
-            WalkResult::NoWalk | WalkResult::PartialWalk => Err(WalkError::CantWalk),
-            WalkResult::FullyWalked(new_context) => Ok(new_context),
-        };
-    }
-    for context in breadcrumbs.iter().rev() {
-        match walk_path_from_single_level(*context, path) {
-            // If no walking was done at all, keep looping
-            WalkResult::NoWalk => {}
-            // If we partially walked then stop trying to find
-            // anything
-            WalkResult::PartialWalk => {
-                return Err(WalkError::CantWalk);
-            }
-            WalkResult::FullyWalked(new_context) => return Ok(new_context),
-        }
-    }
-    Err(WalkError::CantWalk)
-}
-
-pub fn owned_walk_path<'a>(
-    breadcrumbs: &'a Vec<Box<dyn ContextElement>>,
-    path: &Vec<String>,
-) -> Result<&'a dyn ContextElement, WalkError> {
+pub fn walk_path<'a, B, P>(
+    breadcrumbs: &'a Vec<B>,
+    path: &Vec<P>,
+) -> Result<&'a dyn ContextElement, WalkError>
+where
+    B: Borrow<dyn ContextElement + 'a>,
+    P: Borrow<str>,
+{
     if path.is_empty() {
         return Ok(breadcrumbs
             .last()
-            .expect("Breadcrumbs should never be empty")
-            .as_ref());
+            .expect("Breadcrumbs should never be empty.")
+            .borrow());
     }
-
-    let path_reference: Vec<&str> = path.iter().map(|p| &p[..]).collect();
-    if path.first().expect("Already proved path is not empty") == "." {
+    if path
+        .first()
+        .expect("Already proved path is not empty")
+        .borrow()
+        == "."
+    {
         return match walk_path_from_single_level(
             breadcrumbs
                 .last()
-                .expect("Breadcrumbs should never be empty")
-                .as_ref(),
-            &path_reference[1..],
+                .expect("Breadcrumbs should never be empty"),
+            &path[1..],
         ) {
             // If no walking was done at all or we partially walked
             // then stop trying to find anything because '.' restricts
@@ -97,9 +67,8 @@ pub fn owned_walk_path<'a>(
             WalkResult::FullyWalked(new_context) => Ok(new_context),
         };
     }
-
     for context in breadcrumbs.iter().rev() {
-        match walk_path_from_single_level(context.as_ref(), &path_reference) {
+        match walk_path_from_single_level(context, path) {
             // If no walking was done at all, keep looping
             WalkResult::NoWalk => {}
             // If we partially walked then stop trying to find