Merge branch 'dot_leading_path' into render

js/test_cases/dot_leading_path/input1.json

@@ -0,0 +1,7 @@
+{
+  "commander": "Chris",
+  "names": {
+    "captain": "Alice",
+    "first_officer": "Bob"
+  }
+}

js/test_cases/dot_leading_path/main.dust

@@ -0,0 +1,5 @@
+{#names}
+    Hello {.captain}!{~n}
+    Hello {.commander}!{~n}
+    Hello {commander}!{~n}
+{/names}

src/parser/parser.rs

@@ -263,7 +263,14 @@ fn key(i: &str) -> IResult<&str, &str> {
 fn path(i: &str) -> IResult<&str, Path> {
     alt((
         map(separated_list1(tag("."), key), |body| Path { keys: body }),
-        value(Path { keys: Vec::new() }, tag(".")),
+        map(
+            tuple((tag("."), separated_list1(tag("."), key))),
+            |(dot, mut body)| {
+                body.insert(0, dot);
+                Path { keys: body }
+            },
+        ),
+        map(tag("."), |dot| Path { keys: vec![dot] }),
     ))(i)
 }
 
@@ -1210,7 +1217,7 @@ mod tests {
                                 contents: Some(Body {
                                     elements: vec![TemplateElement::TETag(DustTag::DTReference(
                                         Reference {
-                                            path: Path { keys: vec![] },
+                                            path: Path { keys: vec!["."] },
                                             filters: vec![]
                                         }
                                     ))]
@@ -1238,7 +1245,7 @@ mod tests {
                                             IgnoredWhitespace::StartOfLine("\n")
                                         ),
                                         TemplateElement::TETag(DustTag::DTReference(Reference {
-                                            path: Path { keys: vec![] },
+                                            path: Path { keys: vec!["."] },
                                             filters: vec![]
                                         })),
                                         TemplateElement::TEIgnoredWhitespace(

src/renderer/walking.rs

@@ -9,7 +9,7 @@ enum WalkResult<'a> {
 
 fn walk_path_from_single_level<'a>(
     context: &'a dyn ContextElement,
-    path: &Vec<&str>,
+    path: &[&str],
 ) -> WalkResult<'a> {
     if path.is_empty() {
         return WalkResult::FullyWalked(context);
@@ -18,7 +18,6 @@ fn walk_path_from_single_level<'a>(
     let mut walk_failure = WalkResult::NoWalk;
     let mut output = context;
     for elem in path.iter() {
-        let new_val = output.walk(elem);
         match output.walk(elem) {
             Err(WalkError::CantWalk { .. }) => {
                 return walk_failure;
@@ -37,6 +36,25 @@ 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