From cddfddf1c84c9c014f20e1d35df9fcb8dbde04a0 Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Thu, 16 Jan 2020 17:44:26 +1000
Subject: [PATCH] save filters and field name separately

---
 rslib/src/err.rs      |  8 ++++----
 rslib/src/template.rs | 19 ++++++++++++++-----
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/rslib/src/err.rs b/rslib/src/err.rs
index d57eee395..b664dee9e 100644
--- a/rslib/src/err.rs
+++ b/rslib/src/err.rs
@@ -26,7 +26,7 @@ pub enum TemplateError {
     NoClosingBrackets(String),
     ConditionalNotClosed(String),
     ConditionalNotOpen(String),
-    FieldNotFound(String),
+    FieldNotFound { filters: String, field: String },
 }
 
 impl From<TemplateError> for AnkiError {
@@ -40,9 +40,9 @@ impl From<TemplateError> for AnkiError {
                 TemplateError::ConditionalNotOpen(tag) => {
                     format!("missing '{{{{#{}}}}}' or '{{{{^{}}}}}'", tag, tag)
                 }
-                TemplateError::FieldNotFound(field) => format!(
-                    "found '{{{{{}}}}}', but there is no field called '{}'",
-                    field, field
+                TemplateError::FieldNotFound { field, filters } => format!(
+                    "found '{{{{{}{}}}}}', but there is no field called '{}'",
+                    filters, field, field
                 ),
             },
         }
diff --git a/rslib/src/template.rs b/rslib/src/template.rs
index de22b4f81..0858c29a1 100644
--- a/rslib/src/template.rs
+++ b/rslib/src/template.rs
@@ -330,14 +330,17 @@ fn render_into(
                     Some(text) => apply_filters(text, filters, key, context),
                     None => {
                         // unknown field encountered
-                        let name_including_filters = filters
+                        let filters_str = filters
                             .iter()
                             .rev()
                             .cloned()
-                            .chain(iter::once(*key))
+                            .chain(iter::once(""))
                             .collect::<Vec<_>>()
                             .join(":");
-                        return Err(TemplateError::FieldNotFound(name_including_filters));
+                        return Err(TemplateError::FieldNotFound {
+                            field: (*key).to_string(),
+                            filters: filters_str,
+                        });
                     }
                 };
 
@@ -726,14 +729,20 @@ mod test {
         tmpl = PT::from_text("{{X}}").unwrap();
         assert_eq!(
             tmpl.render(&ctx).unwrap_err(),
-            TemplateError::FieldNotFound("X".to_owned())
+            TemplateError::FieldNotFound {
+                field: "X".to_owned(),
+                filters: "".to_owned()
+            }
         );
 
         // unknown field with filters
         tmpl = PT::from_text("{{foo:text:X}}").unwrap();
         assert_eq!(
             tmpl.render(&ctx).unwrap_err(),
-            TemplateError::FieldNotFound("foo:text:X".to_owned())
+            TemplateError::FieldNotFound {
+                field: "X".to_owned(),
+                filters: "foo:text:".to_owned()
+            }
         );
 
         // a blank field is allowed if it has filters