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//! Regression: the `tojson` jinja filter must match transformers'
//! `_compile_jinja_template` override —
//! `json.dumps(x, ensure_ascii=False, indent=indent)`.
//!
//! The previous one-arg `serde_json::to_string` closure
//! (a) rejected the `indent` kwarg HF tool-schema templates use
//! (`{{ tools | tojson(indent=4) }}`) and (b) emitted serde_json's compact
//! `,`/`:` separators instead of Python's `, `/`: `, and would HTML-escape
//! via minijinja's built-in. Assert both the compact and indented forms are
//! byte-identical to Python `json.dumps(..., ensure_ascii=False)`, with
//! non-ASCII preserved (no `\uXXXX`, no `&`/`<` escaping).
#![cfg(feature = "tokenizer-chat")]
use mlxrs::tokenizer::chat::render_jinja;
use serde_json::{Value, json};
fn render(template: &str, tools: &Value, extra: &Value) -> String {
render_jinja(
template,
&json!([]), // messages (unused by these templates)
Some(tools),
false, // add_generation_prompt
false, // continue_final_message
None, // bos_token
None, // eos_token
false, // enable_thinking
extra,
)
.expect("render_jinja")
}
#[test]
fn tojson_indent_kwarg_matches_python_json_dumps() {
// HF tool-schema templates: `{{ tools | tojson(indent=4) }}`. Single-key
// object so the assertion is independent of serde_json's map key order.
let tools = json!([{ "name": "café" }]);
let out = render("{{ tools | tojson(indent=4) }}", &tools, &json!({}));
// Python: json.dumps([{"name": "café"}], ensure_ascii=False, indent=4)
let expected = "[\n {\n \"name\": \"café\"\n }\n]";
assert_eq!(
out, expected,
"tojson(indent=4) must match Python json.dumps"
);
// ensure_ascii=False parity: the non-ASCII char survives verbatim.
assert!(out.contains("café"), "non-ASCII must be preserved");
assert!(
!out.contains("\\u"),
"must not ASCII-escape (ensure_ascii=False)"
);
}
#[test]
fn tojson_plain_matches_python_compact_separators() {
// `{{ x | tojson }}` — Python's default compact form uses `, ` / `: `
// separators (separators=None, indent=None), NOT serde_json's `,`/`:`.
let extra = json!({
"obj": { "name": "café" },
"arr": [1, 2, 3],
});
let out = render("{{ obj | tojson }}|{{ arr | tojson }}", &json!([]), &extra);
// Python: json.dumps({"name": "café"}, ensure_ascii=False) -> {"name": "café"}
// json.dumps([1, 2, 3], ensure_ascii=False) -> [1, 2, 3]
assert_eq!(
out, "{\"name\": \"café\"}|[1, 2, 3]",
"compact tojson must use Python `, `/`: ` separators, non-ASCII preserved"
);
}
#[test]
fn tojson_no_html_escaping() {
// transformers overrides Jinja's built-in *because* it HTML-escapes
// (`<`/`>`/`&`/`'` -> `<` …). Ours must NOT.
let extra = json!({ "s": "a<b>&'\"c" });
let out = render("{{ s | tojson }}", &json!([]), &extra);
// Python: json.dumps("a<b>&'\"c", ensure_ascii=False) -> "a<b>&'\"c"
assert_eq!(out, "\"a<b>&'\\\"c\"");
assert!(!out.contains("\\u00"), "no HTML \\u-escaping");
}
#[test]
fn tojson_positional_indent_arg() {
// minijinja built-in also accepts a positional indent; keep parity so
// `{{ x | tojson(2) }}` works alongside the kwarg form.
let extra = json!({ "v": [1] });
let out = render("{{ v | tojson(2) }}", &json!([]), &extra);
assert_eq!(out, "[\n 1\n]");
}
#[test]
fn tojson_bool_indent_matches_python_bool_as_int() {
// Python `bool` is a subclass of `int`, so HF's
// `json.dumps(x, ensure_ascii=False, indent=<bool>)` treats `False` ≡ 0
// and `True` ≡ 1 (both NOT None → indented path). Expected bytes captured
// from CPython: json.dumps(v, ensure_ascii=False, indent=False|True).
let extra = json!({ "v": [1], "o": { "b": 1, "a": 2 } });
// indent=false ≡ Python indent=0 → newline-separated, empty indent.
assert_eq!(
render("{{ v | tojson(indent=false) }}", &json!([]), &extra),
"[\n1\n]",
"tojson(indent=false) must equal json.dumps(indent=False)=indent=0"
);
// indent=true ≡ Python indent=1 → 1-space indent.
assert_eq!(
render("{{ v | tojson(indent=true) }}", &json!([]), &extra),
"[\n 1\n]",
"tojson(indent=true) must equal json.dumps(indent=True)=indent=1"
);
// Insertion order preserved under the bool-indent path too (preserve_order).
assert_eq!(
render("{{ o | tojson(indent=false) }}", &json!([]), &extra),
"{\n\"b\": 1,\n\"a\": 2\n}"
);
assert_eq!(
render("{{ o | tojson(indent=true) }}", &json!([]), &extra),
"{\n \"b\": 1,\n \"a\": 2\n}"
);
}
#[test]
fn tojson_string_indent_matches_python_json_dumps() {
// Python `json.dumps` accepts a STRING `indent`, used
// verbatim as the per-level indent. Transformers forwards it directly.
// Expected bytes captured from CPython
// json.dumps(v, ensure_ascii=False, indent="<s>").
let extra = json!({ "v": [1], "o": { "b": 1, "a": 2 } });
assert_eq!(
render(r#"{{ v | tojson(indent="--") }}"#, &json!([]), &extra),
"[\n--1\n]",
r#"tojson(indent="--") must equal json.dumps(indent="--")"#
);
// Empty string ≡ Python indent="" → newline, no indent (same as indent=0).
assert_eq!(
render(r#"{{ v | tojson(indent="") }}"#, &json!([]), &extra),
"[\n1\n]"
);
// Tab indent, incl. an insertion-ordered object.
assert_eq!(
render(r#"{{ v | tojson(indent="\t") }}"#, &json!([]), &extra),
"[\n\t1\n]"
);
assert_eq!(
render(r#"{{ o | tojson(indent="\t") }}"#, &json!([]), &extra),
"{\n\t\"b\": 1,\n\t\"a\": 2\n}"
);
}
#[test]
fn tojson_enormous_integer_indent_errors_not_aborts() {
// A model-controlled (untrusted) chat_template calling
// `tojson(indent=<huge int>)` must NOT trigger an unbounded allocation /
// process abort. `render_jinja` must return a recoverable Err instead.
let tools = json!([1]);
for tmpl in [
"{{ tools | tojson(indent=9223372036854775807) }}", // i64::MAX
"{{ tools | tojson(indent=999999999999) }}",
] {
let r = render_jinja(
tmpl,
&json!([]),
Some(&tools),
false, // add_generation_prompt
false, // continue_final_message
None,
None,
false,
&json!({}),
);
assert!(
r.is_err(),
"huge integer indent must return a recoverable error, not abort: {tmpl}"
);
}
// A legitimate indent still works (cap is far above real usage).
assert_eq!(
render("{{ tools | tojson(indent=8) }}", &json!([1]), &json!({})),
"[\n 1\n]"
);
}