Add initial vim mode mode switching

Co-authored-by: Nathan Sobo <nathan@zed.dev>

crates/vim/src/vim_tests.rs

@@ -0,0 +1,152 @@
+use std::ops::Deref;
+
+use editor::{display_map::ToDisplayPoint, DisplayPoint};
+use gpui::{json::json, keymap::Keystroke, AppContext, ViewHandle};
+use language::{Point, Selection};
+use workspace::{WorkspaceHandle, WorkspaceParams};
+
+use crate::*;
+
+#[gpui::test]
+async fn test_insert_mode(cx: &mut gpui::TestAppContext) {
+    let mut cx = VimTestAppContext::new(cx, "").await;
+    assert_eq!(cx.mode(), Mode::Normal);
+    cx.simulate_keystroke("i");
+    assert_eq!(cx.mode(), Mode::Insert);
+    cx.simulate_keystrokes(&["T", "e", "s", "t"]);
+    assert_eq!(cx.editor_text(), "Test".to_owned());
+    cx.simulate_keystroke("escape");
+    assert_eq!(cx.mode(), Mode::Normal);
+}
+
+#[gpui::test]
+async fn test_normal_hjkl(cx: &mut gpui::TestAppContext) {
+    let mut cx = VimTestAppContext::new(cx, "Test\nTestTest\nTest").await;
+    assert_eq!(cx.mode(), Mode::Normal);
+    cx.simulate_keystroke("l");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(0, 1));
+    cx.simulate_keystroke("h");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(0, 0));
+    cx.simulate_keystroke("j");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(1, 0));
+    cx.simulate_keystroke("k");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(0, 0));
+
+    cx.simulate_keystroke("j");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(1, 0));
+
+    // When moving left, cursor does not wrap to the previous line
+    cx.simulate_keystroke("h");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(1, 0));
+
+    // When moving right, cursor does not reach the line end or wrap to the next line
+    for _ in 0..9 {
+        cx.simulate_keystroke("l");
+    }
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(1, 7));
+
+    // Goal column respects the inability to reach the end of the line
+    cx.simulate_keystroke("k");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(0, 3));
+    cx.simulate_keystroke("j");
+    assert_eq!(cx.newest_selection().head(), DisplayPoint::new(1, 7));
+}
+
+struct VimTestAppContext<'a> {
+    cx: &'a mut gpui::TestAppContext,
+    window_id: usize,
+    editor: ViewHandle<Editor>,
+}
+
+impl<'a> VimTestAppContext<'a> {
+    async fn new(
+        cx: &'a mut gpui::TestAppContext,
+        initial_editor_text: &str,
+    ) -> VimTestAppContext<'a> {
+        cx.update(|cx| {
+            editor::init(cx);
+            crate::init(cx);
+        });
+        let params = cx.update(WorkspaceParams::test);
+        params
+            .fs
+            .as_fake()
+            .insert_tree(
+                "/root",
+                json!({ "dir": { "test.txt": initial_editor_text } }),
+            )
+            .await;
+
+        let (window_id, workspace) = cx.add_window(|cx| Workspace::new(&params, cx));
+        params
+            .project
+            .update(cx, |project, cx| {
+                project.find_or_create_local_worktree("/root", true, cx)
+            })
+            .await
+            .unwrap();
+        cx.read(|cx| workspace.read(cx).worktree_scans_complete(cx))
+            .await;
+
+        let file = cx.read(|cx| workspace.file_project_paths(cx)[0].clone());
+        let item = workspace
+            .update(cx, |workspace, cx| workspace.open_path(file, cx))
+            .await
+            .expect("Could not open test file");
+
+        let editor = cx.update(|cx| {
+            item.act_as::<Editor>(cx)
+                .expect("Opened test file wasn't an editor")
+        });
+        editor.update(cx, |_, cx| cx.focus_self());
+
+        Self {
+            cx,
+            window_id,
+            editor,
+        }
+    }
+
+    fn newest_selection(&mut self) -> Selection<DisplayPoint> {
+        self.editor.update(self.cx, |editor, cx| {
+            let snapshot = editor.snapshot(cx);
+            editor
+                .newest_selection::<Point>(cx)
+                .map(|point| point.to_display_point(&snapshot.display_snapshot))
+        })
+    }
+
+    fn mode(&mut self) -> Mode {
+        self.cx.update(|cx| cx.global::<VimState>().mode)
+    }
+
+    fn editor_text(&mut self) -> String {
+        self.editor
+            .update(self.cx, |editor, cx| editor.snapshot(cx).text())
+    }
+
+    fn simulate_keystroke(&mut self, keystroke_text: &str) {
+        let keystroke = Keystroke::parse(keystroke_text).unwrap();
+        let input = if keystroke.modified() {
+            None
+        } else {
+            Some(keystroke.key.clone())
+        };
+        self.cx
+            .dispatch_keystroke(self.window_id, keystroke, input, false);
+    }
+
+    fn simulate_keystrokes(&mut self, keystroke_texts: &[&str]) {
+        for keystroke_text in keystroke_texts.into_iter() {
+            self.simulate_keystroke(keystroke_text);
+        }
+    }
+}
+
+impl<'a> Deref for VimTestAppContext<'a> {
+    type Target = gpui::TestAppContext;
+
+    fn deref(&self) -> &Self::Target {
+        self.cx
+    }
+}