cgen: allow `shared` initialization from return values of functions (#8512)

vlib/v/gen/cgen.v

@@ -2530,6 +2530,19 @@ fn (mut g Gen) expr(node ast.Expr) {
 			// if g.fileis('1.strings') {
 			// println('\ncall_expr()()')
 			// }
+			mut shared_styp := ''
+			if g.is_shared {
+				ret_sym := g.table.get_type_symbol(node.return_type)
+				shared_typ := node.return_type.set_flag(.shared_f)
+				shared_styp = g.typ(shared_typ)
+				if ret_sym.kind == .array {
+					g.writeln('($shared_styp*)__dup_shared_array(&($shared_styp){.val = ')
+				} else if ret_sym.kind == .map {
+					g.writeln('($shared_styp*)__dup_shared_map(&($shared_styp){.val = ')
+				} else {
+					g.writeln('($shared_styp*)__dup${shared_styp}(&($shared_styp){.val = ')
+				}
+			}
 			g.call_expr(node)
 			// if g.fileis('1.strings') {
 			// println('before:' + node.autofree_pregen)
@@ -2546,6 +2559,9 @@ fn (mut g Gen) expr(node ast.Expr) {
 				g.strs_to_free0 = []
 				// println('pos=$node.pos.pos')
 			}
+			if g.is_shared {
+				g.writeln('}, sizeof($shared_styp))')
+			}
 			// if g.autofree && node.autofree_pregen != '' { // g.strs_to_free0.len != 0 {
 			/*
 			if g.autofree {

vlib/v/tests/shared_array_test.v

@@ -46,20 +46,29 @@ fn test_shared_init_syntax() {
 	shared bar := [-12.5, 23.125, 6.0625, 12.5]
 	shared baz := &[]int{len: 5, cap: 12}
 	shared qux := []f64{len: 7}
+	shared quux := new_array()
 	lock foo {
 		foo[2] = 20
 	}
 	lock bar {
 		bar[3] = 12.5
 	}
-	lock baz, qux {
+	lock baz, qux, quux {
 		baz[3] = 12
 		qux[6] = -17.0625
+		quux[2] = 7.0625
 	}
-	rlock foo, bar, baz, qux {
+	rlock foo, bar, baz, qux, quux {
 		assert foo[2] == 20
 		assert bar[3] == 12.5
 		assert baz[3] == 12
 		assert qux[6] == -17.0625
+		assert quux[1] == 6.25
+		assert quux[2] == 7.0625
 	}
 }
+
+fn new_array() []f64 {
+	a := [12.5, 6.25, -3.125, 1.75]
+	return a
+}

vlib/v/tests/shared_map_test.v

@@ -41,20 +41,29 @@ fn test_shared_init_syntax() {
 	shared bar := {'wer': 13.75, 'cvbn': -7.25, 'asd': -0.0625}
 	shared baz := &map[string]int{}
 	shared qux := map[string]f64{}
+	shared quux := new_map()
 	lock foo {
 		foo['q'] = 20
 	}
 	lock bar {
 		bar['asd'] = 12.5
 	}
-	lock baz, qux {
+	lock baz, qux, quux {
 		baz['wer'] = 12
 		qux['abc'] = -17.0625
+		quux['tzu'] = 1.125
 	}
-	rlock foo, bar, baz, qux {
+	rlock foo, bar, baz, qux, quux {
 		assert foo['q'] == 20
 		assert bar['asd'] == 12.5
 		assert baz['wer'] == 12
 		assert qux['abc'] == -17.0625
+		assert quux['tzu'] == 1.125
+		assert quux['yxc'] == 9.125
 	}
 }
+
+fn new_map() map[string]f64 {
+	m := { 'qwe': 34.25, 'yxc': 9.125, 'tzu': -7.5 }
+	return m
+}