json2: replace encoder with new implementation (#25224)

Author: Larsimusrex

cmd/tools/vls.v

@@ -64,12 +64,6 @@ const vls_src_folder = os.join_path(vls_folder, 'src')
 const server_not_found_err = error_with_code('Language server is not installed nor found.',
 	101)
 
-const json_enc = json2.Encoder{
-	newline:              `\n`
-	newline_spaces_count: 2
-	escape_unicode:       false
-}
-
 fn (upd VlsUpdater) check_or_create_vls_folder() ! {
 	if !os.exists(vls_folder) {
 		upd.log('Creating .vls folder...')
@@ -106,22 +100,11 @@ fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp
 		}
 	}
 
-	mut manifest_file := os.open_file(vls_manifest_path, 'w+')!
-	defer {
-		manifest_file.close()
-	}
-
 	manifest['server_path'] = json2.Any(new_path)
 	manifest['last_updated'] = json2.Any(timestamp.format_ss())
 	manifest['from_source'] = json2.Any(from_source)
 
-	mut buffer := []u8{}
-
-	json_enc.encode_value(manifest, mut buffer)!
-
-	manifest_file.write(buffer)!
-
-	unsafe { buffer.free() }
+	os.write_file(vls_manifest_path, json2.encode(manifest))!
 }
 
 fn (upd VlsUpdater) init_download_prebuilt() ! {

vlib/math/big/json_decode.v vlib/math/big/json_custom.vvlib/math/big/json_decode.v renamed to vlib/math/big/json_custom.v

@@ -28,3 +28,8 @@ pub fn (mut result Integer) from_json_number(raw_number string) ! {
 		result = result * integer_from_int(-1)
 	}
 }
+
+// to_json implements a custom encoder for json2
+pub fn (result Integer) to_json() string {
+	return result.str()
+}

vlib/time/json_decode.c.v vlib/time/json_custom.c.vvlib/time/json_decode.c.v renamed to vlib/time/json_custom.c.v

@@ -34,3 +34,8 @@ pub fn (mut t Time) from_json_string(raw_string string) ! {
 
 	return error('Expected iso8601/rfc3339/unix time but got: ${raw_string}')
 }
+
+// to_json implements a custom encoder for json2 (rfc3339)
+pub fn (t Time) to_json() string {
+	return '"' + t.format_rfc3339() + '"'
+}

vlib/toml/tests/testdata/json_encoding_test.out

@@ -1 +1 @@
-{ "\u3072\u3089\u304c\u306a": "\u3072\u3089" }
+{ "ひらがな": "ひら" }

vlib/v/gen/js/sourcemap/basic_test.v

@@ -132,7 +132,7 @@ fn test_simple() {
 
 	json_data := sm.to_json()
 
-	expected := '{"version":3,"file":"hello.js","sourceRoot":"\\/","sources":["hello.v"],"sourcesContent":["fn main(){nprintln(\'Hello World! Helo \$a\')\\n}"],"names":["hello_name"],"mappings":"AAAA;AAAA,EAAA,OAAO,CAACA,GAAR,CAAY,aAAZ,CAAA,CAAA;AAAA"}'
+	expected := '{"version":3,"file":"hello.js","sourceRoot":"/","sources":["hello.v"],"sourcesContent":["fn main(){nprintln(\'Hello World! Helo \$a\')\\n}"],"names":["hello_name"],"mappings":"AAAA;AAAA,EAAA,OAAO,CAACA,GAAR,CAAY,aAAZ,CAAA,CAAA;AAAA"}'
 	assert json_data.str() == expected
 }
 
@@ -153,6 +153,6 @@ fn test_source_null() {
 	}, 3, 1, '')
 	json_data := sm.to_json()
 
-	expected := '{"version":3,"file":"hello.js","sourceRoot":"\\/","sources":["hello.v","hello_lib1.v","hello_lib2.v"],"sourcesContent":[null,null,null],"names":[],"mappings":"CA+\\/\\/\\/\\/\\/HA;CCAA;CCAA"}'
+	expected := '{"version":3,"file":"hello.js","sourceRoot":"/","sources":["hello.v","hello_lib1.v","hello_lib2.v"],"sourcesContent":[null,null,null],"names":[],"mappings":"CA+/////HA;CCAA;CCAA"}'
 	assert json_data.str() == expected
 }

vlib/x/json2/constants.v

@@ -0,0 +1,5 @@
+module json2
+
+const true_string = 'true'
+const false_string = 'false'
+const null_string = 'null'

vlib/x/json2/count.v

@@ -0,0 +1,15 @@
+module json2
+
+// implements encoding json, this is not validated so implementations must be correct
+pub interface JsonEncoder {
+	// to_json returns a string containing an objects json representation
+	to_json() string
+}
+
+// Encodable is an interface, that allows custom implementations for encoding structs to their string based JSON representations.
+
+@[deprecated: 'use `to_json` to implement `JsonEncoder` instead']
+@[deprecated_after: '2025-10-30']
+pub interface Encodable {
+	json_str() string
+}

vlib/x/json2/count_test.v

@@ -16,6 +16,7 @@ struct OptAnyStruct[T] {
 fn test_values() {
 	assert json.decode[AnyStruct[json2.Any]]('{"val":5}')!.val.int() == 5
 	assert json.decode[OptAnyStruct[json2.Any]]('{}')!.val == none
+	assert json.decode[OptAnyStruct[json2.Any]]('{"val":null}')!.val == none
 	assert json.decode[AnyStruct[[]json2.Any]]('{"val":[5,10]}')!.val.map(it.int()) == [
 		5,
 		10,