From 0cc193865729a888a0ef58047cc3af060576fe49 Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Fri, 14 Feb 2020 19:19:40 +1000
Subject: [PATCH] move empty card check into template code

---
 pylib/anki/template.py            |  8 --------
 pylib/tests/test_models.py        |  2 +-
 rslib/src/i18n/card-templates.ftl |  2 ++
 rslib/src/template.rs             | 18 ++++++++++++++++--
 4 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/pylib/anki/template.py b/pylib/anki/template.py
index 238b0764f..0a05aeee1 100644
--- a/pylib/anki/template.py
+++ b/pylib/anki/template.py
@@ -34,7 +34,6 @@ from typing import Any, Dict, List, Optional, Tuple
 import anki
 from anki import hooks
 from anki.cards import Card
-from anki.lang import _
 from anki.models import NoteType
 from anki.notes import Note
 from anki.rsbackend import TemplateReplacementList
@@ -128,13 +127,6 @@ def render_card(
             answer_av_tags=[],
         )
 
-    if not output.question_text.strip():
-        msg = _("The front of this card is blank.")
-        help = _("More info")
-        helplink = CARD_BLANK_HELP
-        msg += f"<br><a href='{helplink}'>{help}</a>"
-        output.question_text = msg
-
     hooks.card_did_render(output, ctx)
 
     return output
diff --git a/pylib/tests/test_models.py b/pylib/tests/test_models.py
index 4c55a13d8..8f6ceecee 100644
--- a/pylib/tests/test_models.py
+++ b/pylib/tests/test_models.py
@@ -223,7 +223,7 @@ def test_typecloze():
     d = getEmptyCol()
     m = d.models.byName("Cloze")
     d.models.setCurrent(m)
-    m["tmpls"][0]["qfmt"] = "{{type:cloze:Text}}"
+    m["tmpls"][0]["qfmt"] = "{{cloze:Text}}{{type:cloze:Text}}"
     d.models.save(m)
     f = d.newNote()
     f["Text"] = "hello {{c1::world}}"
diff --git a/rslib/src/i18n/card-templates.ftl b/rslib/src/i18n/card-templates.ftl
index b3695c7db..08649039d 100644
--- a/rslib/src/i18n/card-templates.ftl
+++ b/rslib/src/i18n/card-templates.ftl
@@ -13,3 +13,5 @@ no-such-field =
   Found '{$found}', but there is no field called '{$field}'
 
 more-info = More information
+
+empty-front = The front of this card is blank.
diff --git a/rslib/src/template.rs b/rslib/src/template.rs
index 9e06f3e33..6ffb04d8a 100644
--- a/rslib/src/template.rs
+++ b/rslib/src/template.rs
@@ -20,6 +20,8 @@ type TemplateResult<T> = std::result::Result<T, TemplateError>;
 
 static TEMPLATE_ERROR_LINK: &str =
     "https://anki.tenderapp.com/kb/problems/card-template-has-a-problem";
+static TEMPLATE_BLANK_LINK: &str =
+    "https://anki.tenderapp.com/kb/card-appearance/the-front-of-this-card-is-blank";
 
 // Lexing
 //----------------------------------------
@@ -500,10 +502,22 @@ pub fn render_card(
 
     // question side
     let qnorm = without_legacy_template_directives(qfmt);
-    let qnodes = ParsedTemplate::from_text(qnorm.as_ref())
-        .and_then(|tmpl| tmpl.render(&context))
+    let (qnodes, qtmpl) = ParsedTemplate::from_text(qnorm.as_ref())
+        .and_then(|tmpl| Ok((tmpl.render(&context)?, tmpl)))
         .map_err(|e| template_error_to_anki_error(e, true, i18n))?;
 
+    // check if the front side was empty
+    if !qtmpl.renders_with_fields(context.nonempty_fields) {
+        let cat = i18n.get(TranslationFile::CardTemplates);
+        let info = format!(
+            "{}<br><a href='{}'>{}</a>",
+            cat.tr("empty-front"),
+            TEMPLATE_BLANK_LINK,
+            cat.tr("more-info")
+        );
+        return Err(AnkiError::TemplateError { info });
+    };
+
     // answer side
     context.question_side = false;
     let anorm = without_legacy_template_directives(afmt);