1 files changed, 138 insertions, 0 deletions
diff --git a/vendor/handlebars/src/json/path.rs b/vendor/handlebars/src/json/path.rs
new file mode 100644
index 000000000..8270371b2
--- /dev/null
+++ b/vendor/handlebars/src/json/path.rs
@@ -0,0 +1,138 @@
+use std::iter::Peekable;
+
+use pest::iterators::Pair;
+use pest::Parser;
+
+use crate::error::RenderError;
+use crate::grammar::{HandlebarsParser, Rule};
+
+#[derive(PartialEq, Clone, Debug)]
+pub enum PathSeg {
+    Named(String),
+    Ruled(Rule),
+}
+
+/// Represents the Json path in templates.
+///
+/// It can be either a local variable like `@first`, `../@index`,
+/// or a normal relative path like `a/b/c`.
+#[derive(PartialEq, Clone, Debug)]
+pub enum Path {
+    Relative((Vec<PathSeg>, String)),
+    Local((usize, String, String)),
+}
+
+impl Path {
+    pub(crate) fn new(raw: &str, segs: Vec<PathSeg>) -> Path {
+        if let Some((level, name)) = get_local_path_and_level(&segs) {
+            Path::Local((level, name, raw.to_owned()))
+        } else {
+            Path::Relative((segs, raw.to_owned()))
+        }
+    }
+
+    pub fn parse(raw: &str) -> Result<Path, RenderError> {
+        HandlebarsParser::parse(Rule::path, raw)
+            .map(|p| {
+                let parsed = p.flatten();
+                let segs = parse_json_path_from_iter(&mut parsed.peekable(), raw.len());
+                Ok(Path::new(raw, segs))
+            })
+            .map_err(|_| RenderError::new("Invalid JSON path"))?
+    }
+
+    pub(crate) fn raw(&self) -> &str {
+        match self {
+            Path::Relative((_, ref raw)) => raw,
+            Path::Local((_, _, ref raw)) => raw,
+        }
+    }
+
+    pub(crate) fn current() -> Path {
+        Path::Relative((Vec::with_capacity(0), "".to_owned()))
+    }
+
+    // for test only
+    pub(crate) fn with_named_paths(name_segs: &[&str]) -> Path {
+        let segs = name_segs
+            .iter()
+            .map(|n| PathSeg::Named((*n).to_string()))
+            .collect();
+        Path::Relative((segs, name_segs.join("/")))
+    }
+
+    // for test only
+    pub(crate) fn segs(&self) -> Option<&[PathSeg]> {
+        match self {
+            Path::Relative((segs, _)) => Some(segs),
+            _ => None,
+        }
+    }
+}
+
+fn get_local_path_and_level(paths: &[PathSeg]) -> Option<(usize, String)> {
+    paths.get(0).and_then(|seg| {
+        if seg == &PathSeg::Ruled(Rule::path_local) {
+            let mut level = 0;
+            while paths.get(level + 1)? == &PathSeg::Ruled(Rule::path_up) {
+                level += 1;
+            }
+            if let Some(PathSeg::Named(name)) = paths.get(level + 1) {
+                Some((level, name.clone()))
+            } else {
+                None
+            }
+        } else {
+            None
+        }
+    })
+}
+
+pub(crate) fn parse_json_path_from_iter<'a, I>(it: &mut Peekable<I>, limit: usize) -> Vec<PathSeg>
+where
+    I: Iterator<Item = Pair<'a, Rule>>,
+{
+    let mut path_stack = Vec::with_capacity(5);
+    while let Some(n) = it.peek() {
+        let span = n.as_span();
+        if span.end() > limit {
+            break;
+        }
+
+        match n.as_rule() {
+            Rule::path_root => {
+                path_stack.push(PathSeg::Ruled(Rule::path_root));
+            }
+            Rule::path_local => {
+                path_stack.push(PathSeg::Ruled(Rule::path_local));
+            }
+            Rule::path_up => {
+                path_stack.push(PathSeg::Ruled(Rule::path_up));
+            }
+            Rule::path_id | Rule::path_raw_id => {
+                let name = n.as_str();
+                if name != "this" {
+                    path_stack.push(PathSeg::Named(name.to_string()));
+                }
+            }
+            _ => {}
+        }
+
+        it.next();
+    }
+
+    path_stack
+}
+
+pub(crate) fn merge_json_path(path_stack: &mut Vec<String>, relative_path: &[PathSeg]) {
+    for seg in relative_path {
+        match seg {
+            PathSeg::Named(ref s) => {
+                path_stack.push(s.to_owned());
+            }
+            PathSeg::Ruled(Rule::path_root) => {}
+            PathSeg::Ruled(Rule::path_up) => {}
+            _ => {}
+        }
+    }
+}