GTK Shell: Manually get/set textual data in clipboard

CHANGELOG.md

@@ -48,6 +48,7 @@ You can find its changes [documented below](#070---2021-01-01).
 ### Fixed
 - `Notification`s will not be delivered to the widget that sends them ([#1640] by [@cmyr])
 - `TextBox` can handle standard keyboard shortcuts without needing menus ([#1660] by [@cmyr])
+- GTK Shell: Prevent mangling of newline characters in clipboard ([#1695] by [@ForLoveOfCats])
 
 
 - Fixed docs of derived Lens ([#1523] by [@Maan2003])
@@ -661,6 +662,7 @@ Last release without a changelog :(
 [#1662]: https://github.com/linebender/druid/pull/1662
 [#1677]: https://github.com/linebender/druid/pull/1677
 [#1698]: https://github.com/linebender/druid/pull/1698
+[#1695]: https://github.com/linebender/druid/pull/1695
 
 [Unreleased]: https://github.com/linebender/druid/compare/v0.7.0...master
 [0.7.0]: https://github.com/linebender/druid/compare/v0.6.0...v0.7.0

druid-shell/src/platform/gtk/clipboard.rs

@@ -19,16 +19,36 @@ use gtk::{TargetEntry, TargetFlags};
 
 use crate::clipboard::{ClipboardFormat, FormatId};
 
+const CLIPBOARD_TARGETS: [&str; 5] = [
+    "UTF8_STRING",
+    "TEXT",
+    "STRING",
+    "text/plain;charset=utf-8",
+    "text/plain",
+];
+
 /// The system clipboard.
 #[derive(Debug, Clone)]
 pub struct Clipboard;
 
 impl Clipboard {
     /// Put a string onto the system clipboard.
-    pub fn put_string(&mut self, s: impl AsRef<str>) {
+    pub fn put_string(&mut self, string: impl AsRef<str>) {
+        let string = string.as_ref().to_string();
+
         let display = gdk::Display::get_default().unwrap();
         let clipboard = gtk::Clipboard::get_default(&display).unwrap();
-        clipboard.set_text(s.as_ref())
+
+        let targets: Vec<TargetEntry> = CLIPBOARD_TARGETS
+            .iter()
+            .enumerate()
+            .map(|(i, target)| TargetEntry::new(target, TargetFlags::all(), i as u32))
+            .collect();
+
+        clipboard.set_with_data(&targets, move |_, selection, _| {
+            const STRIDE_BITS: i32 = 8;
+            selection.set(&selection.get_target(), STRIDE_BITS, string.as_bytes());
+        });
     }
 
     /// Put multi-format data on the system clipboard.
@@ -62,7 +82,15 @@ impl Clipboard {
     pub fn get_string(&self) -> Option<String> {
         let display = gdk::Display::get_default().unwrap();
         let clipboard = gtk::Clipboard::get_default(&display).unwrap();
-        clipboard.wait_for_text().map(|s| s.to_string())
+
+        for target in &CLIPBOARD_TARGETS {
+            let atom = Atom::intern(target);
+            if let Some(selection) = clipboard.wait_for_contents(&atom) {
+                return String::from_utf8(selection.get_data()).ok();
+            }
+        }
+
+        None
     }
 
     /// Given a list of supported clipboard types, returns the supported type which has