x.json2: allow parsing a value from a multidimensional array in map_from (#22442)

Author: esquerbatua

vlib/x/json2/json2.v

@@ -260,12 +260,16 @@ pub fn map_from[T](t T) map[string]Any {
 			value := t.$(field.name)
 
 			$if field.is_array {
-				mut arr := []Any{}
-				for variable in value {
-					arr << Any(variable)
+				mut top_arr := unsafe { []Any{len: t.$(field.name).len} }
+				for idx, variable in value {
+					$if variable is $array {
+						top_arr[idx] = flatten_array(variable)
+					} $else {
+						top_arr[idx] = variable
+					}
 				}
-				m[field.name] = arr
-				arr.clear()
+				m[field.name] = top_arr
+				top_arr.clear()
 			} $else $if field.is_struct {
 				m[field.name] = map_from(value)
 			} $else $if field.is_map {
@@ -275,33 +279,33 @@ pub fn map_from[T](t T) map[string]Any {
 			} $else $if field.is_option {
 				// TODO
 			} $else {
-				// TODO: improve memory usage when convert
+				// TODO: simplify check of type & improve memory usage when convert
 				$if field.typ is string {
-					m[field.name] = value.str()
+					m[field.name] = value
 				} $else $if field.typ is bool {
-					m[field.name] = t.$(field.name).str().bool()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is i8 {
-					m[field.name] = t.$(field.name).str().i8()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is i16 {
-					m[field.name] = t.$(field.name).str().i16()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is i32 {
-					m[field.name] = t.$(field.name).str().i32()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is int {
-					m[field.name] = t.$(field.name).str().int()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is i64 {
-					m[field.name] = t.$(field.name).str().i64()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is f32 {
-					m[field.name] = t.$(field.name).str().f32()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is f64 {
-					m[field.name] = t.$(field.name).str().f64()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is u8 {
-					m[field.name] = t.$(field.name).str().u8()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is u16 {
-					m[field.name] = t.$(field.name).str().u16()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is u32 {
-					m[field.name] = t.$(field.name).str().u32()
+					m[field.name] = t.$(field.name)
 				} $else $if field.typ is u64 {
-					m[field.name] = t.$(field.name).str().u64()
+					m[field.name] = t.$(field.name)
 				} $else {
 					// return error("The type of `${field.name}` can't be decoded. Please open an issue at https://github.com/vlang/v/issues/new/choose")
 				}
@@ -310,3 +314,21 @@ pub fn map_from[T](t T) map[string]Any {
 	}
 	return m
 }
+
+// flatten_array convert a array of values to array of Any
+@[inline]
+fn flatten_array[T](t []T) []Any {
+	$if t !is $array {
+		return Any(t)
+	} $else {
+		mut arr := []Any{}
+		for variable in t {
+			$if variable is $array {
+				arr << flatten_array(variable)
+			} $else {
+				arr << Any(variable)
+			}
+		}
+		return arr
+	}
+}

vlib/x/json2/tests/json2_test.v

@@ -98,6 +98,36 @@ fn test_struct_with_array_to_map() {
 	assert array_of_map.str() == '[{"val":[false,true]},{"val":[true,false]}]'
 }
 
+fn test_struct_with_array_of_arrays_to_map() {
+	array_of_struct := [
+		StructType[[][]bool]{
+			val: [[true, false], [true, false]]
+		},
+		StructType[[][]bool]{
+			val: [[false, true], [false, true]]
+		},
+	]
+	mut array_of_map := []json.Any{}
+	for variable in array_of_struct {
+		array_of_map << json.map_from(variable)
+	}
+	assert array_of_map.str() == '[{"val":[[true,false],[true,false]]},{"val":[[false,true],[false,true]]}]'
+
+	array_of_struct_int := [
+		StructType[[][]int]{
+			val: [[1, 0], [1, 0]]
+		},
+		StructType[[][]int]{
+			val: [[0, 1], [0, 1]]
+		},
+	]
+	mut array_of_map_int := []json.Any{}
+	for variable in array_of_struct_int {
+		array_of_map_int << json.map_from(variable)
+	}
+	assert array_of_map_int.str() == '[{"val":[[1,0],[1,0]]},{"val":[[0,1],[0,1]]}]'
+}
+
 fn test_struct_with_number_to_map() {
 	assert json.map_from(StructType[string]{'3'}).str() == '{"val":"3"}'
 	assert json.map_from(StructType[bool]{true}).str() == '{"val":true}'