to json -r not removing whitespaces fix (#11948)

fixes #11900  

# Description
Use `serde_json` instead.

# User-Facing Changes
The problem described in the issue now no longer persists.

No whitespace in the output of `to json --raw`
Output of unicode escape changed to consistent `\uffff`

# Tests + Formatting
I corrected all Tests that were affected by this change.

crates/nu-command/tests/commands/cal.rs

@@ -5,7 +5,7 @@ fn cal_full_year() {
     let actual = nu!("cal -y --full-year 2010 | first | to json -r");
 
     let first_week_2010_json =
-        r#"{"year": 2010,"su": null,"mo": null,"tu": null,"we": null,"th": null,"fr": 1,"sa": 2}"#;
+        r#"{"year":2010,"su":null,"mo":null,"tu":null,"we":null,"th":null,"fr":1,"sa":2}"#;
 
     assert_eq!(actual.out, first_week_2010_json);
 }
@@ -18,7 +18,7 @@ fn cal_february_2020_leap_year() {
         "#
     ));
 
-    let cal_february_json = r#"[{"year": 2020,"month": "february","su": null,"mo": null,"tu": null,"we": null,"th": null,"fr": null,"sa": 1},{"year": 2020,"month": "february","su": 2,"mo": 3,"tu": 4,"we": 5,"th": 6,"fr": 7,"sa": 8},{"year": 2020,"month": "february","su": 9,"mo": 10,"tu": 11,"we": 12,"th": 13,"fr": 14,"sa": 15},{"year": 2020,"month": "february","su": 16,"mo": 17,"tu": 18,"we": 19,"th": 20,"fr": 21,"sa": 22},{"year": 2020,"month": "february","su": 23,"mo": 24,"tu": 25,"we": 26,"th": 27,"fr": 28,"sa": 29}]"#;
+    let cal_february_json = r#"[{"year":2020,"month":"february","su":null,"mo":null,"tu":null,"we":null,"th":null,"fr":null,"sa":1},{"year":2020,"month":"february","su":2,"mo":3,"tu":4,"we":5,"th":6,"fr":7,"sa":8},{"year":2020,"month":"february","su":9,"mo":10,"tu":11,"we":12,"th":13,"fr":14,"sa":15},{"year":2020,"month":"february","su":16,"mo":17,"tu":18,"we":19,"th":20,"fr":21,"sa":22},{"year":2020,"month":"february","su":23,"mo":24,"tu":25,"we":26,"th":27,"fr":28,"sa":29}]"#;
 
     assert_eq!(actual.out, cal_february_json);
 }
@@ -53,7 +53,7 @@ fn cal_week_day_start_mo() {
         "#
     ));
 
-    let cal_january_json = r#"[{"month": "january","mo": null,"tu": null,"we": 1,"th": 2,"fr": 3,"sa": 4,"su": 5},{"month": "january","mo": 6,"tu": 7,"we": 8,"th": 9,"fr": 10,"sa": 11,"su": 12},{"month": "january","mo": 13,"tu": 14,"we": 15,"th": 16,"fr": 17,"sa": 18,"su": 19},{"month": "january","mo": 20,"tu": 21,"we": 22,"th": 23,"fr": 24,"sa": 25,"su": 26},{"month": "january","mo": 27,"tu": 28,"we": 29,"th": 30,"fr": 31,"sa": null,"su": null}]"#;
+    let cal_january_json = r#"[{"month":"january","mo":null,"tu":null,"we":1,"th":2,"fr":3,"sa":4,"su":5},{"month":"january","mo":6,"tu":7,"we":8,"th":9,"fr":10,"sa":11,"su":12},{"month":"january","mo":13,"tu":14,"we":15,"th":16,"fr":17,"sa":18,"su":19},{"month":"january","mo":20,"tu":21,"we":22,"th":23,"fr":24,"sa":25,"su":26},{"month":"january","mo":27,"tu":28,"we":29,"th":30,"fr":31,"sa":null,"su":null}]"#;
 
     assert_eq!(actual.out, cal_january_json);
 }

crates/nu-command/tests/commands/each.rs

@@ -32,7 +32,7 @@ fn each_window_stride() {
 fn each_no_args_in_block() {
     let actual = nu!("echo [[foo bar]; [a b] [c d] [e f]] | each {|i| $i | to json -r } | get 1");
 
-    assert_eq!(actual.out, r#"{"foo": "c","bar": "d"}"#);
+    assert_eq!(actual.out, r#"{"foo":"c","bar":"d"}"#);
 }
 
 #[test]

crates/nu-command/tests/commands/find.rs

@@ -14,7 +14,7 @@ fn find_with_list_search_with_string() {
 fn find_with_list_search_with_char() {
     let actual = nu!("[moe larry curly] | find l | to json -r");
 
-    assert_eq!(actual.out, "[\"\u{1b}[37m\u{1b}[0m\u{1b}[41;37ml\u{1b}[0m\u{1b}[37marry\u{1b}[0m\",\"\u{1b}[37mcur\u{1b}[0m\u{1b}[41;37ml\u{1b}[0m\u{1b}[37my\u{1b}[0m\"]");
+    assert_eq!(actual.out, "[\"\\u001b[37m\\u001b[0m\\u001b[41;37ml\\u001b[0m\\u001b[37marry\\u001b[0m\",\"\\u001b[37mcur\\u001b[0m\\u001b[41;37ml\\u001b[0m\\u001b[37my\\u001b[0m\"]");
 }
 
 #[test]
@@ -48,7 +48,7 @@ fn find_with_filepath_search_with_string() {
 
     assert_eq!(
         actual.out,
-        "[\"\u{1b}[37m\u{1b}[0m\u{1b}[41;37marep\u{1b}[0m\u{1b}[37mas.clu\u{1b}[0m\"]"
+        "[\"\\u001b[37m\\u001b[0m\\u001b[41;37marep\\u001b[0m\\u001b[37mas.clu\\u001b[0m\"]"
     );
 }
 
@@ -57,7 +57,7 @@ fn find_with_filepath_search_with_multiple_patterns() {
     let actual =
         nu!(r#"["amigos.txt","arepas.clu","los.txt","tres.txt"] | find arep ami | to json -r"#);
 
-    assert_eq!(actual.out, "[\"\u{1b}[37m\u{1b}[0m\u{1b}[41;37mami\u{1b}[0m\u{1b}[37mgos.txt\u{1b}[0m\",\"\u{1b}[37m\u{1b}[0m\u{1b}[41;37marep\u{1b}[0m\u{1b}[37mas.clu\u{1b}[0m\"]");
+    assert_eq!(actual.out, "[\"\\u001b[37m\\u001b[0m\\u001b[41;37mami\\u001b[0m\\u001b[37mgos.txt\\u001b[0m\",\"\\u001b[37m\\u001b[0m\\u001b[41;37marep\\u001b[0m\\u001b[37mas.clu\\u001b[0m\"]");
 }
 
 #[test]

crates/nu-command/tests/commands/math/mod.rs

@@ -420,7 +420,7 @@ fn compound_where() {
         "#
     ));
 
-    assert_eq!(actual.out, r#"[{"a": 2,"b": 1}]"#);
+    assert_eq!(actual.out, r#"[{"a":2,"b":1}]"#);
 }
 
 #[test]
@@ -431,7 +431,7 @@ fn compound_where_paren() {
         "#
     ));
 
-    assert_eq!(actual.out, r#"[{"a": 2,"b": 1},{"a": 2,"b": 2}]"#);
+    assert_eq!(actual.out, r#"[{"a":2,"b":1},{"a":2,"b":2}]"#);
 }
 
 // TODO: these ++ tests are not really testing *math* functionality, maybe find another place for them

crates/nu-command/tests/commands/sort_by.rs

@@ -62,7 +62,7 @@ fn ls_sort_by_name_sensitive() {
         "
     ));
 
-    let json_output = r#"[{"name": "B.txt"},{"name": "C"},{"name": "a.txt"}]"#;
+    let json_output = r#"[{"name":"B.txt"},{"name":"C"},{"name":"a.txt"}]"#;
 
     assert_eq!(actual.out, json_output);
 }
@@ -79,7 +79,7 @@ fn ls_sort_by_name_insensitive() {
         "
     ));
 
-    let json_output = r#"[{"name": "a.txt"},{"name": "B.txt"},{"name": "C"}]"#;
+    let json_output = r#"[{"name":"a.txt"},{"name":"B.txt"},{"name":"C"}]"#;
     assert_eq!(actual.out, json_output);
 }
 
@@ -95,7 +95,7 @@ fn ls_sort_by_type_name_sensitive() {
         "
     ));
 
-    let json_output = r#"[{"name": "C","type": "Dir"},{"name": "B.txt","type": "File"},{"name": "a.txt","type": "File"}]"#;
+    let json_output = r#"[{"name":"C","type":"Dir"},{"name":"B.txt","type":"File"},{"name":"a.txt","type":"File"}]"#;
     assert_eq!(actual.out, json_output);
 }
 
@@ -111,7 +111,7 @@ fn ls_sort_by_type_name_insensitive() {
         "
     ));
 
-    let json_output = r#"[{"name": "C","type": "Dir"},{"name": "a.txt","type": "File"},{"name": "B.txt","type": "File"}]"#;
+    let json_output = r#"[{"name":"C","type":"Dir"},{"name":"a.txt","type":"File"},{"name":"B.txt","type":"File"}]"#;
     assert_eq!(actual.out, json_output);
 }