fix fixed_array slice ommit high_value (#8025)

vlib/v/gen/cgen.v

@@ -3894,6 +3894,10 @@ fn (mut g Gen) index_expr(node ast.IndexExpr) {
 			g.write(', ')
 			if node.index.has_high {
 				g.expr(node.index.high)
+			} else if sym.kind == .array_fixed {
+				g.write('_ARR_LEN(')
+				g.expr(node.left)
+				g.write(')')
 			} else {
 				g.expr(node.left)
 				g.write('.len')

vlib/v/tests/array_slice_test.v

@@ -29,3 +29,11 @@ fn test_access_slice_attribute() {
 	assert access_slice_attribute(mut arr) == 4
 }
 
+fn test_fixed_array_slice() {
+	fixed_array1 := [1, 2, 3]!
+	arr1 := fixed_array1[0..]
+	assert arr1 == [1, 2, 3]
+	fixed_array2 := [[1, 2], [2, 3], [3, 4],[4, 5]]!
+	arr2 := fixed_array2[0..]
+	assert arr2 == [[1, 2], [2, 3], [3, 4],[4, 5]]
+}