Add a json_pretty macro

src/macros.rs

@@ -215,6 +215,7 @@ macro_rules! assert_ron_snapshot {
 }
 
 /// Asserts a `Serialize` snapshot in JSON format.
+/// See also [`assert_json_pretty_snapshot`].
 ///
 /// **Feature:** `json` (to be disabled by default)
 ///
@@ -258,6 +259,51 @@ macro_rules! assert_json_snapshot {
     }};
 }
 
+/// Asserts a `Serialize` snapshot in JSON pretty format.
+/// See also [`assert_json_snapshot`].
+///
+/// **Feature:** `json` (to be disabled by default)
+///
+/// This works exactly like [`assert_yaml_snapshot!`] but serializes in JSON format.
+/// This is normally not recommended because it makes diffs less reliable, but it can
+/// be useful for certain specialized situations.
+///
+/// Example:
+///
+/// ```no_run
+/// # use insta::*;
+/// assert_json_snapshot!(vec![1, 2, 3]);
+/// ```
+///
+/// The third argument to the macro can be an object expression for redaction.
+/// It's in the form `{ selector => replacement }`.  For more information
+/// about redactions refer to the [redactions feature in the guide](https://insta.rs/docs/redactions/).
+///
+/// The snapshot name is optional but can be provided as first argument.
+#[cfg(feature = "json")]
+#[cfg_attr(docsrs, doc(cfg(feature = "json")))]
+#[macro_export]
+macro_rules! assert_json_pretty_snapshot {
+    ($value:expr, @$snapshot:literal) => {{
+        $crate::_assert_serialized_snapshot!($value, JsonPretty, @$snapshot);
+    }};
+    ($value:expr, {$($k:expr => $v:expr),*$(,)?}, @$snapshot:literal) => {{
+        $crate::_assert_serialized_snapshot!($value, {$($k => $v),*}, JsonPretty, @$snapshot);
+    }};
+    ($value:expr, {$($k:expr => $v:expr),*$(,)?}) => {{
+        $crate::_assert_serialized_snapshot!($crate::_macro_support::AutoName, $value, {$($k => $v),*}, JsonPretty);
+    }};
+    ($name:expr, $value:expr) => {{
+        $crate::_assert_serialized_snapshot!(Some($name), $value, JsonPretty);
+    }};
+    ($name:expr, $value:expr, {$($k:expr => $v:expr),*$(,)?}) => {{
+        $crate::_assert_serialized_snapshot!(Some($name), $value, {$($k => $v),*}, JsonPretty);
+    }};
+    ($value:expr) => {{
+        $crate::_assert_serialized_snapshot!($crate::_macro_support::AutoName, $value, JsonPretty);
+    }};
+}
+
 #[doc(hidden)]
 #[macro_export]
 macro_rules! _assert_serialized_snapshot {

src/serialization.rs

@@ -13,6 +13,7 @@ pub enum SerializationFormat {
     Toml,
     Yaml,
     Json,
+    JsonPretty,
 }
 
 pub enum SnapshotLocation {
@@ -46,7 +47,8 @@ pub fn serialize_content(
                 SnapshotLocation::File => serialized[4..].to_string(),
             }
         }
-        SerializationFormat::Json => json::to_string_pretty(&content),
+        SerializationFormat::Json => json::to_string(&content),
+        SerializationFormat::JsonPretty => json::to_string_pretty(&content),
         #[cfg(feature = "csv")]
         SerializationFormat::Csv => {
             let mut buf = Vec::with_capacity(128);

tests/snapshots/test_basic__json_pretty_vector.snap

@@ -0,0 +1,9 @@
+---
+source: tests/test_basic.rs
+expression: "vec![1, 2, 3]"
+---
+[
+  1,
+  2,
+  3
+]

tests/snapshots/test_basic__json_vector.snap

@@ -2,8 +2,4 @@
 source: tests/test_basic.rs
 expression: "vec![1, 2, 3]"
 ---
-[
-  1,
-  2,
-  3
-]
+[1,2,3]

tests/snapshots/test_basic__unnamed_json_pretty_vector-2.snap

@@ -0,0 +1,10 @@
+---
+source: tests/test_basic.rs
+expression: "vec![1, 2, 3, 4]"
+---
+[
+  1,
+  2,
+  3,
+  4
+]

tests/snapshots/test_basic__unnamed_json_pretty_vector-3.snap

@@ -0,0 +1,11 @@
+---
+source: tests/test_basic.rs
+expression: "vec![1, 2, 3, 4, 5]"
+---
+[
+  1,
+  2,
+  3,
+  4,
+  5
+]

tests/snapshots/test_basic__unnamed_json_pretty_vector.snap

@@ -0,0 +1,9 @@
+---
+source: tests/test_basic.rs
+expression: "vec![1, 2, 3]"
+---
+[
+  1,
+  2,
+  3
+]

tests/snapshots/test_basic__unnamed_json_vector-2.snap

@@ -2,9 +2,4 @@
 source: tests/test_basic.rs
 expression: "vec![1, 2, 3, 4]"
 ---
-[
-  1,
-  2,
-  3,
-  4
-]
+[1,2,3,4]

tests/snapshots/test_basic__unnamed_json_vector-3.snap

@@ -2,10 +2,4 @@
 source: tests/test_basic.rs
 expression: "vec![1, 2, 3, 4, 5]"
 ---
-[
-  1,
-  2,
-  3,
-  4,
-  5
-]
+[1,2,3,4,5]

tests/snapshots/test_basic__unnamed_json_vector.snap

@@ -2,8 +2,4 @@
 source: tests/test_basic.rs
 expression: "vec![1, 2, 3]"
 ---
-[
-  1,
-  2,
-  3
-]
+[1,2,3]

tests/test_basic.rs

@@ -1,8 +1,8 @@
-#[cfg(feature = "json")]
-use insta::assert_json_snapshot;
 #[cfg(feature = "yaml")]
 use insta::assert_yaml_snapshot;
 use insta::{assert_debug_snapshot, assert_display_snapshot};
+#[cfg(feature = "json")]
+use insta::{assert_json_pretty_snapshot, assert_json_snapshot};
 use std::fmt;
 
 #[test]
@@ -55,6 +55,20 @@ fn test_unnamed_json_vector() {
     assert_json_snapshot!(vec![1, 2, 3, 4, 5]);
 }
 
+#[cfg(feature = "json")]
+#[test]
+fn test_json_pretty_vector() {
+    assert_json_pretty_snapshot!("json_pretty_vector", vec![1, 2, 3]);
+}
+
+#[cfg(feature = "json")]
+#[test]
+fn test_unnamed_json_pretty_vector() {
+    assert_json_pretty_snapshot!(vec![1, 2, 3]);
+    assert_json_pretty_snapshot!(vec![1, 2, 3, 4]);
+    assert_json_pretty_snapshot!(vec![1, 2, 3, 4, 5]);
+}
+
 mod nested {
     #[test]
     fn test_nested_module() {

tests/test_inline.rs

@@ -166,12 +166,7 @@ fn test_toml_inline() {
 #[cfg(feature = "json")]
 #[test]
 fn test_json_inline() {
-    assert_json_snapshot!(vec!["foo", "bar"], @r###"
-    [
-      "foo",
-      "bar"
-    ]
-    "###);
+    assert_json_snapshot!(vec!["foo", "bar"], @r###"["foo","bar"]"###);
 }
 
 #[cfg(feature = "yaml")]