--- /dev/null
+use std::iter::repeat;
+
+fn main() {
+ resize_vector();
+ extend_vector();
+ mixed_extend_resize_vector();
+}
+
+fn extend_vector() {
+ // Extend with constant expression
+ let len = 300;
+ let mut vec1 = Vec::with_capacity(len);
+ vec1.extend(repeat(0).take(len));
+
+ // Extend with len expression
+ let mut vec2 = Vec::with_capacity(len - 10);
+ vec2.extend(repeat(0).take(len - 10));
+
+ // Extend with mismatching expression should not be warned
+ let mut vec3 = Vec::with_capacity(24322);
+ vec3.extend(repeat(0).take(2));
+}
+
+fn mixed_extend_resize_vector() {
+ // Mismatching len
+ let mut mismatching_len = Vec::with_capacity(30);
+ mismatching_len.extend(repeat(0).take(40));
+
+ // Slow initialization
+ let mut resized_vec = Vec::with_capacity(30);
+ resized_vec.resize(30, 0);
+
+ let mut extend_vec = Vec::with_capacity(30);
+ extend_vec.extend(repeat(0).take(30));
+}
+
+fn resize_vector() {
+ // Resize with constant expression
+ let len = 300;
+ let mut vec1 = Vec::with_capacity(len);
+ vec1.resize(len, 0);
+
+ // Resize mismatch len
+ let mut vec2 = Vec::with_capacity(200);
+ vec2.resize(10, 0);
+
+ // Resize with len expression
+ let mut vec3 = Vec::with_capacity(len - 10);
+ vec3.resize(len - 10, 0);
+
+ // Reinitialization should be warned
+ vec1 = Vec::with_capacity(10);
+ vec1.resize(10, 0);
+}
+
+fn do_stuff(vec: &mut Vec<u8>) {}
+
+fn extend_vector_with_manipulations_between() {
+ let len = 300;
+ let mut vec1: Vec<u8> = Vec::with_capacity(len);
+ do_stuff(&mut vec1);
+ vec1.extend(repeat(0).take(len));
+}