1 files changed, 106 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/checked_conversions.rs b/src/tools/clippy/tests/ui/checked_conversions.rs
new file mode 100644
index 00000000000..a643354e243
--- /dev/null
+++ b/src/tools/clippy/tests/ui/checked_conversions.rs
@@ -0,0 +1,106 @@
+// run-rustfix
+
+#![warn(clippy::checked_conversions)]
+#![allow(clippy::cast_lossless)]
+#![allow(dead_code)]
+use std::convert::TryFrom;
+
+// Positive tests
+
+// Signed to unsigned
+
+fn i64_to_u32(value: i64) -> Option<u32> {
+    if value <= (u32::max_value() as i64) && value >= 0 {
+        Some(value as u32)
+    } else {
+        None
+    }
+}
+
+fn i64_to_u16(value: i64) -> Option<u16> {
+    if value <= i64::from(u16::max_value()) && value >= 0 {
+        Some(value as u16)
+    } else {
+        None
+    }
+}
+
+fn isize_to_u8(value: isize) -> Option<u8> {
+    if value <= (u8::max_value() as isize) && value >= 0 {
+        Some(value as u8)
+    } else {
+        None
+    }
+}
+
+// Signed to signed
+
+fn i64_to_i32(value: i64) -> Option<i32> {
+    if value <= (i32::max_value() as i64) && value >= (i32::min_value() as i64) {
+        Some(value as i32)
+    } else {
+        None
+    }
+}
+
+fn i64_to_i16(value: i64) -> Option<i16> {
+    if value <= i64::from(i16::max_value()) && value >= i64::from(i16::min_value()) {
+        Some(value as i16)
+    } else {
+        None
+    }
+}
+
+// Unsigned to X
+
+fn u32_to_i32(value: u32) -> Option<i32> {
+    if value <= i32::max_value() as u32 {
+        Some(value as i32)
+    } else {
+        None
+    }
+}
+
+fn usize_to_isize(value: usize) -> isize {
+    if value <= isize::max_value() as usize && value as i32 == 5 {
+        5
+    } else {
+        1
+    }
+}
+
+fn u32_to_u16(value: u32) -> isize {
+    if value <= u16::max_value() as u32 && value as i32 == 5 {
+        5
+    } else {
+        1
+    }
+}
+
+// Negative tests
+
+fn no_i64_to_i32(value: i64) -> Option<i32> {
+    if value <= (i32::max_value() as i64) && value >= 0 {
+        Some(value as i32)
+    } else {
+        None
+    }
+}
+
+fn no_isize_to_u8(value: isize) -> Option<u8> {
+    if value <= (u8::max_value() as isize) && value >= (u8::min_value() as isize) {
+        Some(value as u8)
+    } else {
+        None
+    }
+}
+
+fn i8_to_u8(value: i8) -> Option<u8> {
+    if value >= 0 {
+        Some(value as u8)
+    } else {
+        None
+    }
+}
+
+fn main() {}