json2.decoder2: prepare decoder in json2 to be replaced by json2.deco…

…de2 (vlang#23078)

cmd/tools/vls.v

@@ -79,7 +79,7 @@ fn (upd VlsUpdater) check_or_create_vls_folder() ! {
 
 fn (upd VlsUpdater) manifest_config() !map[string]json2.Any {
 	manifest_buf := os.read_file(vls_manifest_path) or { '{}' }
-	manifest_contents := json2.raw_decode(manifest_buf)!.as_map()
+	manifest_contents := json2.decode[json2.Any](manifest_buf)!.as_map()
 	return manifest_contents
 }
 
@@ -168,7 +168,7 @@ fn (upd VlsUpdater) download_prebuilt() ! {
 
 	upd.log('Finding prebuilt executables from GitHub release..')
 	resp := http.get('https://api.github.com/repos/vlang/vls/releases')!
-	releases_json := json2.raw_decode(resp.body)!.arr()
+	releases_json := json2.decode[json2.Any](resp.body)!.arr()
 	if releases_json.len == 0 {
 		return error('Unable to fetch latest VLS release data: No releases found.')
 	}

vlib/v/slow_tests/valgrind/import_x_json2.v

@@ -2,5 +2,5 @@ import x.json2
 
 fn main() {
 	x := '[[],[],[]]'
-	println(json2.raw_decode(x)!)
+	println(json2.decode[json2.Any](x)!)
 }

vlib/x/json2/README.md

@@ -77,7 +77,7 @@ fn main() {
 	resp := http.get('https://reqres.in/api/products/1')!
 
 	// This returns an Any type
-	raw_product := json2.raw_decode(resp.body)!
+	raw_product := json2.decode[json2.Any](resp.body)!
 }
 ```
 
@@ -90,7 +90,7 @@ import net.http
 fn main() {
 	resp := http.get('https://reqres.in/api/products/1')!
 
-	raw_product := json2.raw_decode(resp.body)!
+	raw_product := json2.decode[json2.Any](resp.body)!
 
 	product := raw_product.as_map()
 	data := product['data'] as map[string]json2.Any
@@ -174,4 +174,4 @@ json2.encode_value(<some value to be encoded here>, mut buffer)!
 sb.write(buffer)!
 
 unsafe { buffer.free() }
-```
+```

vlib/x/json2/decoder.v

@@ -60,16 +60,13 @@ fn new_parser(srce string, convert_type bool) Parser {
 
 // decode is a generic function that decodes a JSON string into the target type.
 pub fn decode[T](src string) !T {
+	$if T is Any {
+		return raw_decode(src)!
+	}
 	res := raw_decode(src)!.as_map()
 	return decode_struct[T](T{}, res)
 }
 
-// decode_array is a generic function that decodes a JSON string into the array target type.
-pub fn decode_array[T](src string) ![]T {
-	res := raw_decode(src)!.as_map()
-	return decode_struct_array(T{}, res)
-}
-
 // decode_struct_array is a generic function that decodes a JSON map into array struct T.
 fn decode_struct_array[T](_ T, res map[string]Any) ![]T {
 	$if T is $struct {
@@ -428,6 +425,7 @@ fn (mut p Parser) decode_array() !Any {
 	return Any(items)
 }
 
+@[deprecated_after: '2025-03-18']
 fn (mut p Parser) decode_object() !Any {
 	mut fields := map[string]Any{}
 	p.next_with_err()!

vlib/x/json2/decoder2/decode.v

@@ -777,10 +777,25 @@ fn (mut decoder Decoder) decode_value[T](mut val T) ! {
 										}
 
 										if current_field_info.value.is_raw {
-											$if field.typ is $enum {
+											$if field.unaliased_typ is $enum {
 												// workaround to avoid the error: enums can only be assigned `int` values
 												return error('`raw` attribute cannot be used with enum fields')
-											} $else $if field.typ is string || field.typ is ?string {
+											} $else $if field.typ is ?string {
+												position := decoder.current_node.value.position
+												end := position + decoder.current_node.value.length
+
+												val.$(field.name) = decoder.json[position..end]
+												decoder.current_node = decoder.current_node.next
+
+												for {
+													if decoder.current_node == unsafe { nil }
+														|| decoder.current_node.value.position + decoder.current_node.value.length >= end {
+														break
+													}
+
+													decoder.current_node = decoder.current_node.next
+												}
+											} $else $if field.typ is string {
 												position := decoder.current_node.value.position
 												end := position + decoder.current_node.value.length
 

vlib/x/json2/decoder2/decode_sumtype.v

@@ -6,9 +6,15 @@ fn (mut decoder Decoder) get_decoded_sumtype_workaround[T](initialized_sumtype T
 	$if initialized_sumtype is $sumtype {
 		$for v in initialized_sumtype.variants {
 			if initialized_sumtype is v {
-				mut val := initialized_sumtype
-				decoder.decode_value(mut val)!
-				return T(val)
+				$if v is $array {
+					mut val := initialized_sumtype.clone()
+					decoder.decode_value(mut val)!
+					return T(val)
+				} $else {
+					mut val := initialized_sumtype
+					decoder.decode_value(mut val)!
+					return T(val)
+				}
 			}
 		}
 	}

vlib/x/json2/decoder2/decoder_deprecated.v

@@ -0,0 +1,8 @@
+module decoder2
+
+// decode_array is a generic function that decodes a JSON string into the array target type.
+@[deprecated: 'use `decode` instead']
+@[deprecated_after: '2025-03-18']
+pub fn decode_array[T](src string) !T {
+	return decode[T](src)
+}

vlib/x/json2/decoder2/tests/json_sumtype_test.v

@@ -1,6 +1,5 @@
 import x.json2.decoder2 as json
 import x.json2
-import time
 
 type Prices = Price | []Price
 

vlib/x/json2/decoder_deprecated.v

@@ -7,11 +7,13 @@ pub struct DecodeError {
 }
 
 // code returns the error code of DecodeError
+@[deprecated_after: '2025-03-18']
 pub fn (err DecodeError) code() int {
 	return 3
 }
 
 // msg returns the message of the DecodeError
+@[deprecated_after: '2025-03-18']
 pub fn (err DecodeError) msg() string {
 	return format_message(err.message, err.line, err.column)
 }
@@ -23,11 +25,13 @@ pub struct InvalidTokenError {
 }
 
 // code returns the error code of the InvalidTokenError
+@[deprecated_after: '2025-03-18']
 pub fn (err InvalidTokenError) code() int {
 	return 2
 }
 
 // msg returns the message of the InvalidTokenError
+@[deprecated_after: '2025-03-18']
 pub fn (err InvalidTokenError) msg() string {
 	footer_text := if err.expected != .none { ', expecting `${err.expected}`' } else { '' }
 	return format_message('invalid token `${err.token.kind}`${footer_text}', err.token.line,
@@ -41,11 +45,13 @@ pub struct UnknownTokenError {
 }
 
 // code returns the error code of the UnknownTokenError
+@[deprecated_after: '2025-03-18']
 pub fn (err UnknownTokenError) code() int {
 	return 1
 }
 
 // msg returns the error message of the UnknownTokenError
+@[deprecated_after: '2025-03-18']
 pub fn (err UnknownTokenError) msg() string {
 	return format_message("unknown token '${err.token.lit}' when decoding ${err.kind}.",
 		err.token.line, err.token.full_col())
@@ -68,12 +74,15 @@ pub fn raw_decode(src string) !Any {
 }
 
 // Same with `raw_decode`, but skips the type conversion for certain types when decoding a certain value.
+@[deprecated: 'use `decode[json.Any]` instead']
+@[deprecated_after: '2025-03-18']
 pub fn fast_raw_decode(src string) !Any {
 	mut p := new_parser(src, false)
 	return p.decode()
 }
 
 // decode - decodes provided JSON
+@[deprecated_after: '2025-03-18']
 pub fn (mut p Parser) decode() !Any {
 	p.next()
 	p.next_with_err()!
@@ -85,3 +94,11 @@ pub fn (mut p Parser) decode() !Any {
 	}
 	return fi
 }
+
+// decode_array is a generic function that decodes a JSON string into the array target type.
+@[deprecated: 'use `decode` instead']
+@[deprecated_after: '2025-03-18']
+pub fn decode_array[T](src string) ![]T {
+	res := raw_decode(src)!.as_map()
+	return decode_struct_array(T{}, res)
+}

vlib/x/json2/encoder.v

@@ -100,7 +100,7 @@ fn encode_array[T](val []T) string {
 // encode_pretty ...
 pub fn encode_pretty[T](typed_data T) string {
 	encoded := encode(typed_data)
-	raw_decoded := raw_decode(encoded) or { 0 }
+	raw_decoded := decode[Any](encoded) or { 0 }
 	return raw_decoded.prettify_json_str()
 }
 

vlib/x/json2/tests/decode_map_test.v

@@ -1,5 +1,3 @@
-module main
-
 import x.json2
 
 const data = '
@@ -31,7 +29,7 @@ const data = '
 }
 '
 
-struct Comment {
+pub struct Comment {
 	id      string
 	message string
 }