graphlog: refactor out node symbols from GraphLog

Now as default and elided node symbols come from the config, the next logical
step is to use them directly bypassing GraphLog. Note that commands like `jj op
log` and `jj obslog` do not use the elided node symbol at all.

cli/src/commands/log.rs

@@ -118,8 +118,8 @@ pub(crate) fn cmd_log(
 
         if !args.no_graph {
             let mut graph = get_graphlog(command.settings(), formatter.raw());
-            let default_node_symbol = graph.default_node_symbol().to_owned();
-            let elided_node_symbol = graph.elided_node_symbol().to_owned();
+            let default_node_symbol = command.settings().default_node_symbol();
+            let elided_node_symbol = command.settings().elided_node_symbol();
             let forward_iter = TopoGroupedRevsetGraphIterator::new(revset.iter_graph());
             let iter: Box<dyn Iterator<Item = _>> = if args.reversed {
                 Box::new(ReverseRevsetGraphIterator::new(forward_iter))

cli/src/commands/obslog.rs

@@ -90,7 +90,7 @@ pub(crate) fn cmd_obslog(
     }
     if !args.no_graph {
         let mut graph = get_graphlog(command.settings(), formatter.raw());
-        let default_node_symbol = graph.default_node_symbol().to_owned();
+        let default_node_symbol = command.settings().default_node_symbol();
         for commit in commits {
             let mut edges = vec![];
             for predecessor in &commit.predecessors() {

cli/src/commands/operation.rs

@@ -177,7 +177,7 @@ fn cmd_op_log(
     let iter = op_walk::walk_ancestors(&head_ops).take(args.limit.unwrap_or(usize::MAX));
     if !args.no_graph {
         let mut graph = get_graphlog(command.settings(), formatter.raw());
-        let default_node_symbol = graph.default_node_symbol().to_owned();
+        let default_node_symbol = command.settings().default_node_symbol();
         for op in iter {
             let op = op?;
             let mut edges = vec![];

cli/src/graphlog.rs

@@ -37,18 +37,12 @@ pub trait GraphLog<K: Clone + Eq + Hash> {
         text: &str,
     ) -> io::Result<()>;
 
-    fn default_node_symbol(&self) -> &str;
-
-    fn elided_node_symbol(&self) -> &str;
-
     fn width(&self, id: &K, edges: &[Edge<K>]) -> usize;
 }
 
 pub struct SaplingGraphLog<'writer, R> {
     renderer: R,
     writer: &'writer mut dyn Write,
-    default_node_symbol: String,
-    elided_node_symbol: String,
 }
 
 impl<K: Clone> From<&Edge<K>> for Ancestor<K> {
@@ -83,14 +77,6 @@ where
         write!(self.writer, "{row}")
     }
 
-    fn default_node_symbol(&self) -> &str {
-        &self.default_node_symbol
-    }
-
-    fn elided_node_symbol(&self) -> &str {
-        &self.elided_node_symbol
-    }
-
     fn width(&self, id: &K, edges: &[Edge<K>]) -> usize {
         let parents = edges.iter().map_into().collect();
         let w: u64 = self.renderer.width(Some(id), Some(&parents));
@@ -102,8 +88,6 @@ impl<'writer, R> SaplingGraphLog<'writer, R> {
     pub fn create<K>(
         renderer: R,
         formatter: &'writer mut dyn Write,
-        default_node_symbol: &str,
-        elided_node_symbol: &str,
     ) -> Box<dyn GraphLog<K> + 'writer>
     where
         K: Clone + Eq + Hash + 'writer,
@@ -112,8 +96,6 @@ impl<'writer, R> SaplingGraphLog<'writer, R> {
         Box::new(SaplingGraphLog {
             renderer,
             writer: formatter,
-            default_node_symbol: default_node_symbol.to_owned(),
-            elided_node_symbol: elided_node_symbol.to_owned(),
         })
     }
 }
@@ -123,34 +105,13 @@ pub fn get_graphlog<'a, K: Clone + Eq + Hash + 'a>(
     formatter: &'a mut dyn Write,
 ) -> Box<dyn GraphLog<K> + 'a> {
     let builder = GraphRowRenderer::new().output().with_min_row_height(0);
-
-    let (default_node_symbol, elided_node_symbol) = settings.node_symbols();
-
     match settings.graph_style().as_str() {
-        "square" => SaplingGraphLog::create(
-            builder.build_box_drawing().with_square_glyphs(),
-            formatter,
-            &default_node_symbol,
-            &elided_node_symbol,
-        ),
-        "ascii" => SaplingGraphLog::create(
-            builder.build_ascii(),
-            formatter,
-            &default_node_symbol,
-            &elided_node_symbol,
-        ),
-        "ascii-large" => SaplingGraphLog::create(
-            builder.build_ascii_large(),
-            formatter,
-            &default_node_symbol,
-            &elided_node_symbol,
-        ),
+        "square" => {
+            SaplingGraphLog::create(builder.build_box_drawing().with_square_glyphs(), formatter)
+        }
+        "ascii" => SaplingGraphLog::create(builder.build_ascii(), formatter),
+        "ascii-large" => SaplingGraphLog::create(builder.build_ascii_large(), formatter),
         // "curved"
-        _ => SaplingGraphLog::create(
-            builder.build_box_drawing(),
-            formatter,
-            &default_node_symbol,
-            &elided_node_symbol,
-        ),
+        _ => SaplingGraphLog::create(builder.build_box_drawing(), formatter),
     }
 }

lib/src/settings.rs

@@ -242,19 +242,12 @@ impl UserSettings {
             .unwrap_or_else(|_| "curved".to_string())
     }
 
-    pub fn node_symbols(&self) -> (String, String) {
-        let default_node_symbol = self.config.get_string("ui.graph.default_node");
-        let elided_node_symbol = self.config.get_string("ui.graph.elided_node");
-        match self.graph_style().as_str() {
-            "ascii" | "ascii-large" => (
-                default_node_symbol.unwrap_or("o".to_owned()),
-                elided_node_symbol.unwrap_or(".".to_owned()),
-            ),
-            _ => (
-                default_node_symbol.unwrap_or("◉".to_owned()),
-                elided_node_symbol.unwrap_or("◌".to_owned()),
-            ),
-        }
+    pub fn default_node_symbol(&self) -> String {
+        self.node_symbol_for_key("ui.graph.default_node", "◉", "o")
+    }
+
+    pub fn elided_node_symbol(&self) -> String {
+        self.node_symbol_for_key("ui.graph.elided_node", "◌", ".")
     }
 
     pub fn max_new_file_size(&self) -> Result<u64, config::ConfigError> {
@@ -279,6 +272,14 @@ impl UserSettings {
     pub fn sign_settings(&self) -> SignSettings {
         SignSettings::from_settings(self)
     }
+
+    fn node_symbol_for_key(&self, key: &str, fallback: &str, ascii_fallback: &str) -> String {
+        let symbol = self.config.get_string(key);
+        match self.graph_style().as_str() {
+            "ascii" | "ascii-large" => symbol.unwrap_or_else(|_| ascii_fallback.to_owned()),
+            _ => symbol.unwrap_or_else(|_| fallback.to_owned()),
+        }
+    }
 }
 
 /// This Rng uses interior mutability to allow generating random values using an