add jump-label-follow-blacklist, an option that allows removing certain key combinations from the possible jump labels.

book/src/editor.md

@@ -51,6 +51,7 @@
 | `popup-border` | Draw border around `popup`, `menu`, `all`, or `none` | `none` |
 | `indent-heuristic` | How the indentation for a newly inserted line is computed: `simple` just copies the indentation level from the previous line, `tree-sitter` computes the indentation based on the syntax tree and `hybrid` combines both approaches. If the chosen heuristic is not available, a different one will be used as a fallback (the fallback order being `hybrid` -> `tree-sitter` -> `simple`). | `hybrid`
 | `jump-label-alphabet` | The characters that are used to generate two character jump labels. Characters at the start of the alphabet are used first. | `"abcdefghijklmnopqrstuvwxyz"`
+| `jump-label-follow-blacklist` | Used to remove jump label combinations that are hard to type. For example, to make the labels "fj" and "fy" not used, set this option to `{ f = "jy" }` | `{}`
 | `end-of-line-diagnostics` | Minimum severity of diagnostics to render at the end of the line. Set to `disable` to disable entirely. Refer to the setting about `inline-diagnostics` for more details | "disable"
 
 ### `[editor.statusline]` Section

helix-term/src/commands.rs

@@ -6152,15 +6152,52 @@ fn extend_to_word(cx: &mut Context) {
 }
 
 fn jump_to_label(cx: &mut Context, labels: Vec<Range>, behaviour: Movement) {
-    let doc = doc!(cx.editor);
-    let alphabet = &cx.editor.config().jump_label_alphabet;
     if labels.is_empty() {
         return;
     }
-    let alphabet_char = |i| {
-        let mut res = Tendril::new();
-        res.push(alphabet[i]);
-        res
+
+    let doc = doc!(cx.editor);
+    let alphabet = &cx.editor.config().jump_label_alphabet;
+    let follow_blacklist = &cx.editor.config().jump_label_follow_blacklist;
+    let jump_label_lookup = follow_blacklist.get_allow_list(alphabet);
+    let partial_sums = jump_label_lookup
+        .alphabet
+        .iter()
+        .map(|c| jump_label_lookup.follow_whitelist.get(c).unwrap())
+        .map(|v| v.len())
+        .fold(vec![0], |mut acc, curr| {
+            acc.push(acc.last().unwrap() + curr);
+            acc
+        });
+
+    let make_jump_label = |i| {
+        // finding, based on the total number of overlays generated so far, what the index into the
+        // first characters and second characters respectively should be.
+        let first_i = partial_sums.iter().take_while(|p| p <= &&i).count() - 1;
+
+        let second_i = i - partial_sums
+            .get(first_i)
+            .unwrap_or_else(|| panic!("first_i outside of partial_sums indices."));
+
+        let first = *jump_label_lookup.alphabet.get(first_i).unwrap_or_else(|| {
+            panic!(
+                "alphabet_char called with i ({}) greater than the number of valid pairs ({}).",
+                i,
+                partial_sums.last().unwrap()
+            )
+        });
+
+        let second = jump_label_lookup.follow_whitelist.get(&first)
+                .unwrap_or_else(|| {
+                    panic!("there should not be any first chars created which don't have entries in follow_whitelist.")
+                })[second_i];
+
+        let mut first_res = Tendril::new();
+        let mut second_res = Tendril::new();
+
+        first_res.push(first);
+        second_res.push(second);
+        (first_res, second_res)
     };
 
     // Add label for each jump candidate to the View as virtual text.
@@ -6169,15 +6206,18 @@ fn jump_to_label(cx: &mut Context, labels: Vec<Range>, behaviour: Movement) {
         .iter()
         .enumerate()
         .flat_map(|(i, range)| {
+            let (first_grapheme, second_grapheme) = make_jump_label(i);
+
             [
-                Overlay::new(range.from(), alphabet_char(i / alphabet.len())),
+                Overlay::new(range.from(), first_grapheme),
                 Overlay::new(
                     graphemes::next_grapheme_boundary(text, range.from()),
-                    alphabet_char(i % alphabet.len()),
+                    second_grapheme,
                 ),
             ]
         })
         .collect();
+
     overlays.sort_unstable_by_key(|overlay| overlay.char_idx);
     let (view, doc) = current!(cx.editor);
     doc.set_jump_labels(view.id, overlays);
@@ -6188,15 +6228,17 @@ fn jump_to_label(cx: &mut Context, labels: Vec<Range>, behaviour: Movement) {
     let view = view.id;
     let doc = doc.id();
     cx.on_next_key(move |cx, event| {
-        let alphabet = &cx.editor.config().jump_label_alphabet;
-        let Some(i) = event
-            .char()
-            .and_then(|ch| alphabet.iter().position(|&it| it == ch))
-        else {
+        let Some((first_ch, i)) = event.char().and_then(|ch| {
+            jump_label_lookup
+                .alphabet
+                .iter()
+                .position(|&it| it == ch)
+                .map(|i| (ch, i))
+        }) else {
             doc_mut!(cx.editor, &doc).remove_jump_labels(view);
             return;
         };
-        let outer = i * alphabet.len();
+        let outer = partial_sums[i];
         // Bail if the given character cannot be a jump label.
         if outer > labels.len() {
             doc_mut!(cx.editor, &doc).remove_jump_labels(view);
@@ -6204,13 +6246,17 @@ fn jump_to_label(cx: &mut Context, labels: Vec<Range>, behaviour: Movement) {
         }
         cx.on_next_key(move |cx, event| {
             doc_mut!(cx.editor, &doc).remove_jump_labels(view);
-            let alphabet = &cx.editor.config().jump_label_alphabet;
-            let Some(inner) = event
-                .char()
-                .and_then(|ch| alphabet.iter().position(|&it| it == ch))
-            else {
+            let Some(inner) = event.char().and_then(|ch| {
+                jump_label_lookup
+                    .follow_whitelist
+                    .get(&first_ch)
+                    .unwrap_or(&vec![])
+                    .iter()
+                    .position(|&it| it == ch)
+            }) else {
                 return;
             };
+
             if let Some(mut range) = labels.get(outer + inner).copied() {
                 range = if behaviour == Movement::Extend {
                     let anchor = if range.anchor < range.head {
@@ -6242,7 +6288,13 @@ fn jump_to_word(cx: &mut Context, behaviour: Movement) {
     // Calculate the jump candidates: ranges for any visible words with two or
     // more characters.
     let alphabet = &cx.editor.config().jump_label_alphabet;
-    let jump_label_limit = alphabet.len() * alphabet.len();
+    let follow_blacklist = &cx.editor.config().jump_label_follow_blacklist;
+    let jump_label_lookup = follow_blacklist.get_allow_list(alphabet);
+    let jump_label_limit = jump_label_lookup
+        .follow_whitelist
+        .values()
+        .map(|v| v.len())
+        .sum();
     let mut words = Vec::with_capacity(jump_label_limit);
     let (view, doc) = current_ref!(cx.editor);
     let text = doc.text().slice(..);

helix-view/src/editor.rs

@@ -21,7 +21,7 @@ use helix_lsp::{Call, LanguageServerId};
 use tokio_stream::wrappers::UnboundedReceiverStream;
 
 use std::{
-    borrow::Cow,
+    borrow::{Borrow, Cow},
     cell::Cell,
     collections::{BTreeMap, HashMap, HashSet},
     fs,
@@ -342,11 +342,117 @@ pub struct Config {
         deserialize_with = "deserialize_alphabet"
     )]
     pub jump_label_alphabet: Vec<char>,
+    // characters not allowed to follow each starting character
+    pub jump_label_follow_blacklist: JumpLabelFollowBlacklist,
     /// Display diagnostic below the line they occur.
     pub inline_diagnostics: InlineDiagnosticsConfig,
     pub end_of_line_diagnostics: DiagnosticFilter,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct JumpLabelFollowBlacklist(HashMap<char, Vec<char>>);
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct JumpLabelLookup {
+    pub alphabet: Vec<char>,
+    pub follow_whitelist: HashMap<char, Vec<char>>,
+}
+
+impl JumpLabelFollowBlacklist {
+    pub fn get(&self, c: char) -> Option<&Vec<char>> {
+        self.0.get(&c)
+    }
+
+    pub fn get_allow_list(&self, alphabet: &Vec<char>) -> JumpLabelLookup {
+        let follow_whitelist: HashMap<_, _> = alphabet
+            .iter()
+            .filter_map(|c| {
+                let unique_chars: HashSet<_> = alphabet.iter().copied().collect();
+                let blacklist_chars: Option<HashSet<_>> =
+                    self.get(*c).and_then(|v| Some(v.iter().copied().collect()));
+
+                let whitelist_chars = if let Some(blacklist_chars) = blacklist_chars {
+                    unique_chars
+                        .symmetric_difference(&blacklist_chars)
+                        .map(|c| *c)
+                        .collect()
+                } else {
+                    alphabet.clone()
+                };
+
+                if whitelist_chars.len() > 0 {
+                    Some((*c, whitelist_chars))
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        let alphabet = alphabet
+            .iter()
+            .filter_map(|c| {
+                if follow_whitelist.contains_key(c) {
+                    Some(*c)
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        JumpLabelLookup {
+            alphabet,
+            follow_whitelist,
+        }
+    }
+}
+
+impl Serialize for JumpLabelFollowBlacklist {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        self.0
+            .iter()
+            .map(|(k, v)| (*k, v.iter().collect::<String>()))
+            .collect::<HashMap<_, _>>()
+            .serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for JumpLabelFollowBlacklist {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        use serde::de::Error;
+
+        let map = HashMap::<char, String>::deserialize(deserializer)?;
+
+        let map = map
+            .into_iter()
+            .map(|(k, v)| {
+                let chars: Vec<_> = v.chars().collect();
+                let unique_chars: HashSet<_> = chars.iter().copied().collect();
+                if unique_chars.len() != chars.len() {
+                    return Err(<D::Error as Error>::custom(
+                        "jump-label-follow-blacklist lists must contain unique characters",
+                    ));
+                }
+
+                Ok((k, chars))
+            })
+            .collect::<Result<HashMap<_, _>, _>>()?;
+
+        Ok(Self(map))
+    }
+}
+
+impl Default for JumpLabelFollowBlacklist {
+    fn default() -> Self {
+        Self(HashMap::new())
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Deserialize, Serialize, Eq, PartialOrd, Ord)]
 #[serde(rename_all = "kebab-case", default)]
 pub struct SmartTabConfig {
@@ -980,6 +1086,7 @@ impl Default for Config {
             popup_border: PopupBorderConfig::None,
             indent_heuristic: IndentationHeuristic::default(),
             jump_label_alphabet: ('a'..='z').collect(),
+            jump_label_follow_blacklist: JumpLabelFollowBlacklist::default(),
             inline_diagnostics: InlineDiagnosticsConfig::default(),
             end_of_line_diagnostics: DiagnosticFilter::Disable,
         }