3 files changed, 25 insertions, 18 deletions
diff --git a/askama_shared/Cargo.toml b/askama_shared/Cargo.toml
index e19ad35..ea9e968 100644
--- a/askama_shared/Cargo.toml
+++ b/askama_shared/Cargo.toml
@@ -12,7 +12,7 @@ edition = "2018"
 [features]
 default = ["config", "humansize", "num-traits", "percent-encoding"]
 config = ["serde", "toml"]
-json = ["serde", "serde_json"]
+json = ["serde", "serde_json", "askama_escape/json"]
 markdown = ["comrak"]
 yaml = ["serde", "serde_yaml"]
 
diff --git a/askama_shared/src/filters/json.rs b/askama_shared/src/filters/json.rs
index c0df707..e94e50c 100644
--- a/askama_shared/src/filters/json.rs
+++ b/askama_shared/src/filters/json.rs
@@ -1,33 +1,40 @@
 use crate::error::{Error, Result};
-use askama_escape::{Escaper, MarkupDisplay};
+use askama_escape::JsonEscapeBuffer;
 use serde::Serialize;
+use serde_json::to_writer_pretty;
 
-/// Serialize to JSON (requires `serde_json` feature)
+/// Serialize to JSON (requires `json` feature)
 ///
-/// ## Errors
+/// The generated string does not contain ampersands `&`, chevrons `< >`, or apostrophes `'`.
+/// To use it in a `<script>` you can combine it with the safe filter:
 ///
-/// This will panic if `S`'s implementation of `Serialize` decides to fail,
-/// or if `T` contains a map with non-string keys.
-pub fn json<E: Escaper, S: Serialize>(e: E, s: S) -> Result<MarkupDisplay<E, String>> {
-    match serde_json::to_string_pretty(&s) {
-        Ok(s) => Ok(MarkupDisplay::new_safe(s, e)),
-        Err(e) => Err(Error::from(e)),
-    }
+/// ``` html
+/// <script>
+/// var data = {{data|json|safe}};
+/// </script>
+/// ```
+///
+/// To use it in HTML attributes, you can either use it in quotation marks `"{{data|json}}"` as is,
+/// or in apostrophes with the (optional) safe filter `'{{data|json|safe}}'`.
+/// In HTML texts the output of e.g. `<pre>{{data|json|safe}}</pre>` is safe, too.
+pub fn json<S: Serialize>(s: S) -> Result<String> {
+    let mut writer = JsonEscapeBuffer::new();
+    to_writer_pretty(&mut writer, &s).map_err(Error::from)?;
+    Ok(writer.finish())
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
-    use askama_escape::Html;
 
     #[test]
     fn test_json() {
-        assert_eq!(json(Html, true).unwrap().to_string(), "true");
-        assert_eq!(json(Html, "foo").unwrap().to_string(), r#""foo""#);
-        assert_eq!(json(Html, &true).unwrap().to_string(), "true");
-        assert_eq!(json(Html, &"foo").unwrap().to_string(), r#""foo""#);
+        assert_eq!(json(true).unwrap(), "true");
+        assert_eq!(json("foo").unwrap(), r#""foo""#);
+        assert_eq!(json(&true).unwrap(), "true");
+        assert_eq!(json(&"foo").unwrap(), r#""foo""#);
         assert_eq!(
-            json(Html, &vec!["foo", "bar"]).unwrap().to_string(),
+            json(&vec!["foo", "bar"]).unwrap(),
             r#"[
   "foo",
   "bar"
diff --git a/askama_shared/src/generator.rs b/askama_shared/src/generator.rs
index 6024436..ea22a83 100644
--- a/askama_shared/src/generator.rs
+++ b/askama_shared/src/generator.rs
@@ -1171,7 +1171,7 @@ impl<'a, S: std::hash::BuildHasher> Generator<'a, S> {
             return Err("the `yaml` filter requires the `serde-yaml` feature to be enabled".into());
         }
 
-        const FILTERS: [&str; 3] = ["safe", "json", "yaml"];
+        const FILTERS: [&str; 2] = ["safe", "yaml"];
         if FILTERS.contains(&name) {
             buf.write(&format!(
                 "::askama::filters::{}({}, ",