editor: Expand selection to word under cursor before expanding to next enclosing syntax node (#28864)

Closes #27995

For strings in any language and Markdown, `select_larger_syntax_node`
will first select the word and then expand from there if:
- The cursor is on the word.
- The selection is inside the word.

It will not select the word and will directly proceed to expand if:
- The word is already selected.
- Multiple partial words are selected.

Todo:
- [x] Tests

Release Notes:

- Fixed `select_larger_syntax_node` to first expand to the word within a
string, and then to the larger syntax node.

crates/editor/src/editor.rs

@@ -12519,6 +12519,45 @@ impl Editor {
             .iter()
             .map(|selection| {
                 let old_range = selection.start..selection.end;
+
+                if let Some((node, _)) = buffer.syntax_ancestor(old_range.clone()) {
+                    // manually select word at selection
+                    if ["string_content", "inline"].contains(&node.kind()) {
+                        let word_range = {
+                            let display_point = buffer
+                                .offset_to_point(old_range.start)
+                                .to_display_point(&display_map);
+                            let Range { start, end } =
+                                movement::surrounding_word(&display_map, display_point);
+                            start.to_point(&display_map).to_offset(&buffer)
+                                ..end.to_point(&display_map).to_offset(&buffer)
+                        };
+                        // ignore if word is already selected
+                        if !word_range.is_empty() && old_range != word_range {
+                            let last_word_range = {
+                                let display_point = buffer
+                                    .offset_to_point(old_range.end)
+                                    .to_display_point(&display_map);
+                                let Range { start, end } =
+                                    movement::surrounding_word(&display_map, display_point);
+                                start.to_point(&display_map).to_offset(&buffer)
+                                    ..end.to_point(&display_map).to_offset(&buffer)
+                            };
+                            // only select word if start and end point belongs to same word
+                            if word_range == last_word_range {
+                                selected_larger_node = true;
+                                return Selection {
+                                    id: selection.id,
+                                    start: word_range.start,
+                                    end: word_range.end,
+                                    goal: SelectionGoal::None,
+                                    reversed: selection.reversed,
+                                };
+                            }
+                        }
+                    }
+                }
+
                 let mut new_range = old_range.clone();
                 let mut new_node = None;
                 while let Some((node, containing_range)) = buffer.syntax_ancestor(new_range.clone())

crates/editor/src/editor_tests.rs

@@ -6309,7 +6309,187 @@ async fn test_select_larger_smaller_syntax_node(cx: &mut TestAppContext) {
                 use mod1::mod2::«{mod3, mod4}ˇ»;
 
                 fn fn_1«ˇ(param1: bool, param2: &str)» {
-                    «ˇlet var1 = "text";»
+                    let var1 = "«ˇtext»";
+                }
+            "#},
+            cx,
+        );
+    });
+}
+
+#[gpui::test]
+async fn test_select_larger_smaller_syntax_node_for_string(cx: &mut TestAppContext) {
+    init_test(cx, |_| {});
+
+    let language = Arc::new(Language::new(
+        LanguageConfig::default(),
+        Some(tree_sitter_rust::LANGUAGE.into()),
+    ));
+
+    let text = r#"
+        use mod1::mod2::{mod3, mod4};
+
+        fn fn_1(param1: bool, param2: &str) {
+            let var1 = "hello world";
+        }
+    "#
+    .unindent();
+
+    let buffer = cx.new(|cx| Buffer::local(text, cx).with_language(language, cx));
+    let buffer = cx.new(|cx| MultiBuffer::singleton(buffer, cx));
+    let (editor, cx) = cx.add_window_view(|window, cx| build_editor(buffer, window, cx));
+
+    editor
+        .condition::<crate::EditorEvent>(cx, |editor, cx| !editor.buffer.read(cx).is_parsing(cx))
+        .await;
+
+    // Test 1: Cursor on a letter of a string word
+    editor.update_in(cx, |editor, window, cx| {
+        editor.change_selections(None, window, cx, |s| {
+            s.select_display_ranges([
+                DisplayPoint::new(DisplayRow(3), 17)..DisplayPoint::new(DisplayRow(3), 17)
+            ]);
+        });
+    });
+    editor.update_in(cx, |editor, window, cx| {
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "hˇello world";
+                }
+            "#},
+            cx,
+        );
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "«ˇhello» world";
+                }
+            "#},
+            cx,
+        );
+    });
+
+    // Test 2: Partial selection within a word
+    editor.update_in(cx, |editor, window, cx| {
+        editor.change_selections(None, window, cx, |s| {
+            s.select_display_ranges([
+                DisplayPoint::new(DisplayRow(3), 17)..DisplayPoint::new(DisplayRow(3), 19)
+            ]);
+        });
+    });
+    editor.update_in(cx, |editor, window, cx| {
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "h«elˇ»lo world";
+                }
+            "#},
+            cx,
+        );
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "«ˇhello» world";
+                }
+            "#},
+            cx,
+        );
+    });
+
+    // Test 3: Complete word already selected
+    editor.update_in(cx, |editor, window, cx| {
+        editor.change_selections(None, window, cx, |s| {
+            s.select_display_ranges([
+                DisplayPoint::new(DisplayRow(3), 16)..DisplayPoint::new(DisplayRow(3), 21)
+            ]);
+        });
+    });
+    editor.update_in(cx, |editor, window, cx| {
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "«helloˇ» world";
+                }
+            "#},
+            cx,
+        );
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "«hello worldˇ»";
+                }
+            "#},
+            cx,
+        );
+    });
+
+    // Test 4: Selection spanning across words
+    editor.update_in(cx, |editor, window, cx| {
+        editor.change_selections(None, window, cx, |s| {
+            s.select_display_ranges([
+                DisplayPoint::new(DisplayRow(3), 19)..DisplayPoint::new(DisplayRow(3), 24)
+            ]);
+        });
+    });
+    editor.update_in(cx, |editor, window, cx| {
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "hel«lo woˇ»rld";
+                }
+            "#},
+            cx,
+        );
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    let var1 = "«ˇhello world»";
+                }
+            "#},
+            cx,
+        );
+    });
+
+    // Test 5: Expansion beyond string
+    editor.update_in(cx, |editor, window, cx| {
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        editor.select_larger_syntax_node(&SelectLargerSyntaxNode, window, cx);
+        assert_text_with_selections(
+            editor,
+            indoc! {r#"
+                use mod1::mod2::{mod3, mod4};
+
+                fn fn_1(param1: bool, param2: &str) {
+                    «ˇlet var1 = "hello world";»
                 }
             "#},
             cx,