[testing] serial testing preserving terminal

Cargo.toml

@@ -75,6 +75,7 @@ futures = "0.3"
 futures-timer = "3.0"
 async-std = "1.12"
 serde_json = "1.0"
+serial_test = "2.0.0"
 
 #
 # Examples

src/cursor/sys/windows.rs

@@ -207,13 +207,18 @@ impl From<Handle> for ScreenBufferCursor {
 
 #[cfg(test)]
 mod tests {
+    use serial_test::serial;
     use super::{
         move_down, move_left, move_right, move_to, move_to_column, move_to_next_line,
         move_to_previous_line, move_to_row, move_up, position, restore_position, save_position,
     };
+    use crate::terminal::sys::temp_screen_buffer;
 
     #[test]
+    #[serial]
     fn test_move_to_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         let (saved_x, saved_y) = position().unwrap();
 
         move_to(saved_x + 1, saved_y + 1).unwrap();
@@ -224,14 +229,20 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_right_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         let (saved_x, saved_y) = position().unwrap();
         move_right(1).unwrap();
         assert_eq!(position().unwrap(), (saved_x + 1, saved_y));
     }
 
     #[test]
+    #[serial]
     fn test_move_left_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(2, 0).unwrap();
 
         move_left(2).unwrap();
@@ -240,7 +251,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_up_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 2).unwrap();
 
         move_up(2).unwrap();
@@ -249,7 +263,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_to_next_line_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 2).unwrap();
 
         move_to_next_line(2).unwrap();
@@ -258,7 +275,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_to_previous_line_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 2).unwrap();
 
         move_to_previous_line(2).unwrap();
@@ -267,7 +287,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_to_column_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 2).unwrap();
 
         move_to_column(12).unwrap();
@@ -276,7 +299,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_to_row_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 2).unwrap();
 
         move_to_row(5).unwrap();
@@ -285,7 +311,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_move_down_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         move_to(0, 0).unwrap();
 
         move_down(2).unwrap();
@@ -294,7 +323,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_save_restore_position_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         let (saved_x, saved_y) = position().unwrap();
 
         save_position().unwrap();

src/style/types/color.rs

@@ -366,6 +366,7 @@ mod tests {
     }
 }
 
+
 #[cfg(test)]
 #[cfg(feature = "serde")]
 mod serde_tests {

src/terminal/sys.rs

@@ -13,6 +13,10 @@ pub(crate) use self::windows::{
     clear, disable_raw_mode, enable_raw_mode, is_raw_mode_enabled, scroll_down, scroll_up,
     set_size, set_window_title, size,
 };
+#[cfg(all(windows, test))]
+pub(crate) use self::windows::{
+    temp_screen_buffer,
+};
 
 #[cfg(windows)]
 mod windows;

src/terminal/sys/windows.rs

@@ -341,21 +341,54 @@ fn clear_winapi(
     Ok(())
 }
 
+#[cfg(test)]
+// Create a new screen buffer to avoid changing the terminal the test
+// is running within.
+pub fn temp_screen_buffer() -> std::io::Result<ScreenBuffer> {
+    let alternate_screen = ScreenBuffer::create()?;
+    alternate_screen.show().unwrap();
+    Ok(alternate_screen)
+}
+
 #[cfg(test)]
 mod tests {
     use std::{ffi::OsString, os::windows::ffi::OsStringExt};
 
     use crossterm_winapi::ScreenBuffer;
+    use serial_test::serial;
     use winapi::um::wincon::GetConsoleTitleW;
 
-    use super::{scroll_down, scroll_up, set_size, set_window_title, size};
+    use super::{scroll_down, scroll_up, set_size, set_window_title, size, temp_screen_buffer};
 
     #[test]
-    fn test_resize_winapi() {
+    #[serial]
+    fn test_resize_winapi_20_21() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         let (width, height) = size().unwrap();
 
-        set_size(30, 30).unwrap();
-        assert_eq!((30, 30), size().unwrap());
+        // The values 20 and 21 are arbitrary and different from each other
+        // just to see they're not crossed over.
+        set_size(20, 21).unwrap();
+        assert_eq!((20, 21), size().unwrap());
+
+        // reset to previous size
+        set_size(width, height).unwrap();
+        assert_eq!((width, height), size().unwrap());
+    }
+
+    // This is similar to test_resize_winapi_20_21() above. This verifies that
+    // another test of similar functionality runs independently (that a testing
+    // race condition has been addressed).
+    #[test]
+    #[serial]
+    fn test_resize_winapi_30_31() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
+        let (width, height) = size().unwrap();
+
+        set_size(30, 31).unwrap();
+        assert_eq!((30, 31), size().unwrap());
 
         // reset to previous size
         set_size(width, height).unwrap();
@@ -410,7 +443,10 @@ mod tests {
     }
 
     #[test]
+    #[serial]
     fn test_set_title_winapi() {
+        let _test_screen = temp_screen_buffer().unwrap();
+
         let test_title = "this is a crossterm test title";
         set_window_title(test_title).unwrap();