From 24d2c1831c6db4e790a4e05dbcfd5da3ba833694 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sun, 12 Apr 2020 21:26:23 -0400
Subject: [PATCH] Handle missing references

---
 js/test_cases/missing_reference/input1.json | 1 +
 js/test_cases/missing_reference/main.dust   | 1 +
 src/renderer/renderer.rs                    | 9 +++++++--
 3 files changed, 9 insertions(+), 2 deletions(-)
 create mode 100644 js/test_cases/missing_reference/input1.json
 create mode 100644 js/test_cases/missing_reference/main.dust

diff --git a/js/test_cases/missing_reference/input1.json b/js/test_cases/missing_reference/input1.json
new file mode 100644
index 0000000..8bffc80
--- /dev/null
+++ b/js/test_cases/missing_reference/input1.json
@@ -0,0 +1 @@
+{"rank": "Admiral"}
diff --git a/js/test_cases/missing_reference/main.dust b/js/test_cases/missing_reference/main.dust
new file mode 100644
index 0000000..09f2e19
--- /dev/null
+++ b/js/test_cases/missing_reference/main.dust
@@ -0,0 +1 @@
+Hello {name}!
diff --git a/src/renderer/renderer.rs b/src/renderer/renderer.rs
index dcdbc8a..e28aa94 100644
--- a/src/renderer/renderer.rs
+++ b/src/renderer/renderer.rs
@@ -87,8 +87,13 @@ impl<'a> DustRenderer<'a> {
         match tag {
             DustTag::DTComment(_comment) => (),
             DustTag::DTReference(reference) => {
-                let val = walk_path(context, &reference.path.keys)?;
-                return val.render();
+                let val = walk_path(context, &reference.path.keys);
+                if let Err(RenderError::WontWalk { .. }) = val {
+                    // If reference does not exist in the context, it becomes an empty string
+                    return Ok("".to_owned());
+                } else {
+                    return val?.render();
+                }
             }
             _ => (), // TODO: Implement the rest
         }