1 files changed, 93 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/manual_while_let_some.rs b/src/tools/clippy/tests/ui/manual_while_let_some.rs
new file mode 100644
index 00000000000..85a0a084a42
--- /dev/null
+++ b/src/tools/clippy/tests/ui/manual_while_let_some.rs
@@ -0,0 +1,93 @@
+//@run-rustfix
+
+#![allow(unused)]
+#![warn(clippy::manual_while_let_some)]
+
+struct VecInStruct {
+    numbers: Vec<i32>,
+    unrelated: String,
+}
+
+struct Foo {
+    a: i32,
+    b: i32,
+}
+
+fn accept_i32(_: i32) {}
+fn accept_optional_i32(_: Option<i32>) {}
+fn accept_i32_tuple(_: (i32, i32)) {}
+
+fn main() {
+    let mut numbers = vec![1, 2, 3, 4, 5];
+    while !numbers.is_empty() {
+        let number = numbers.pop().unwrap();
+    }
+
+    let mut val = VecInStruct {
+        numbers: vec![1, 2, 3, 4, 5],
+        unrelated: String::new(),
+    };
+    while !val.numbers.is_empty() {
+        let number = val.numbers.pop().unwrap();
+    }
+
+    while !numbers.is_empty() {
+        accept_i32(numbers.pop().unwrap());
+    }
+
+    while !numbers.is_empty() {
+        accept_i32(numbers.pop().expect(""));
+    }
+
+    // This should not warn. It "conditionally" pops elements.
+    while !numbers.is_empty() {
+        if true {
+            accept_i32(numbers.pop().unwrap());
+        }
+    }
+
+    // This should also not warn. It conditionally pops elements.
+    while !numbers.is_empty() {
+        if false {
+            continue;
+        }
+        accept_i32(numbers.pop().unwrap());
+    }
+
+    // This should not warn. It pops elements, but does not unwrap it.
+    // Might handle the Option in some other arbitrary way.
+    while !numbers.is_empty() {
+        accept_optional_i32(numbers.pop());
+    }
+
+    let unrelated_vec: Vec<String> = Vec::new();
+    // This should not warn. It pops elements from a different vector.
+    while !unrelated_vec.is_empty() {
+        accept_i32(numbers.pop().unwrap());
+    }
+
+    macro_rules! generate_loop {
+        () => {
+            while !numbers.is_empty() {
+                accept_i32(numbers.pop().unwrap());
+            }
+        };
+    }
+    // Do not warn if the loop comes from a macro.
+    generate_loop!();
+
+    // Try other kinds of patterns
+    let mut numbers = vec![(0, 0), (1, 1), (2, 2)];
+    while !numbers.is_empty() {
+        let (a, b) = numbers.pop().unwrap();
+    }
+
+    while !numbers.is_empty() {
+        accept_i32_tuple(numbers.pop().unwrap());
+    }
+
+    let mut results = vec![Foo { a: 1, b: 2 }, Foo { a: 3, b: 4 }];
+    while !results.is_empty() {
+        let Foo { a, b } = results.pop().unwrap();
+    }
+}