1 files changed, 87 insertions, 0 deletions
diff --git a/helix-term/tests/integration/helpers.rs b/helix-term/tests/integration/helpers.rs
new file mode 100644
index 00000000..d22bcc3c
--- /dev/null
+++ b/helix-term/tests/integration/helpers.rs
@@ -0,0 +1,87 @@
+use crossterm::event::{Event, KeyEvent};
+use helix_core::{test, Selection, Transaction};
+use helix_term::{application::Application, args::Args, config::Config};
+use helix_view::{doc, input::parse_macro};
+
+#[derive(Clone, Debug)]
+pub struct TestCase {
+    pub in_text: String,
+    pub in_selection: Selection,
+    pub in_keys: String,
+    pub out_text: String,
+    pub out_selection: Selection,
+}
+
+impl<S: Into<String>> From<(S, S, S)> for TestCase {
+    fn from((input, keys, output): (S, S, S)) -> Self {
+        let (in_text, in_selection) = test::print(&input.into());
+        let (out_text, out_selection) = test::print(&output.into());
+
+        TestCase {
+            in_text,
+            in_selection,
+            in_keys: keys.into(),
+            out_text,
+            out_selection,
+        }
+    }
+}
+
+pub fn test_key_sequence<T: Into<TestCase>>(
+    app: Option<Application>,
+    test_case: T,
+    test_fn: &dyn Fn(&mut Application),
+) -> anyhow::Result<()> {
+    let test_case = test_case.into();
+    let mut app =
+        app.unwrap_or_else(|| Application::new(Args::default(), Config::default()).unwrap());
+
+    let (view, doc) = helix_view::current!(app.editor);
+    let sel = doc.selection(view.id).clone();
+
+    // replace the initial text with the input text
+    doc.apply(
+        &Transaction::change_by_selection(&doc.text(), &sel, |_| {
+            (0, doc.text().len_chars(), Some((&test_case.in_text).into()))
+        })
+        .with_selection(test_case.in_selection.clone()),
+        view.id,
+    );
+
+    let input_keys = parse_macro(&test_case.in_keys)?
+        .into_iter()
+        .map(|key_event| Event::Key(KeyEvent::from(key_event)));
+
+    for key in input_keys {
+        app.handle_terminal_events(Ok(key));
+    }
+
+    test_fn(&mut app);
+
+    Ok(())
+}
+
+/// Use this for very simple test cases where there is one input
+/// document, selection, and sequence of key presses, and you just
+/// want to verify the resulting document and selection.
+pub fn test_key_sequence_text_result<T: Into<TestCase>>(
+    args: Args,
+    config: Config,
+    test_case: T,
+) -> anyhow::Result<()> {
+    let test_case = test_case.into();
+    let app = Application::new(args, config).unwrap();
+
+    test_key_sequence(Some(app), test_case.clone(), &|app| {
+        let doc = doc!(app.editor);
+        assert_eq!(&test_case.out_text, doc.text());
+
+        let mut selections: Vec<_> = doc.selections().values().cloned().collect();
+        assert_eq!(1, selections.len());
+
+        let sel = selections.pop().unwrap();
+        assert_eq!(test_case.out_selection, sel);
+    })?;
+
+    Ok(())
+}