create indent-plugin

app/syntax/indent-plugins.ts

@@ -0,0 +1,79 @@
+import { indentWithTab } from "@codemirror/commands";
+import { indentService, indentUnit, syntaxTree } from "@codemirror/language";
+import {
+  type DecorationSet,
+  type EditorView,
+  type ViewUpdate,
+  Decoration,
+  ViewPlugin,
+  WidgetType,
+  keymap,
+} from "@codemirror/view";
+
+class IndentWidget extends WidgetType {
+  constructor(readonly bullet: boolean) {
+    super();
+  }
+  toDOM() {
+    const indent = document.createElement("span");
+    indent.textContent = this.bullet ? "•" : " ";
+    indent.style.paddingInline = "0.5em";
+    return indent;
+  }
+}
+
+function indentDecorations(view: EditorView) {
+  const decorations: Array<{
+    from: number;
+    to: number;
+    value: Decoration;
+  }> = [];
+  for (const { from, to } of view.visibleRanges) {
+    syntaxTree(view.state).iterate({
+      from,
+      to,
+      enter(node) {
+        if (node.name === "Indent") {
+          const next = view.state.doc.sliceString(node.to, node.to + 1);
+          const decoration = Decoration.widget({
+            widget: new IndentWidget(/^[^ \t]?$/.test(next)),
+          });
+          decorations.push(decoration.range(node.from));
+        }
+      },
+    });
+  }
+  return Decoration.set(decorations);
+}
+
+const indentDecorationsPlugin = ViewPlugin.fromClass(
+  class {
+    decorations: DecorationSet;
+    constructor(view: EditorView) {
+      this.decorations = indentDecorations(view);
+    }
+    update(update: ViewUpdate) {
+      if (update.docChanged || update.viewportChanged) {
+        this.decorations = indentDecorations(update.view);
+      }
+    }
+  },
+  {
+    decorations(v) {
+      return v.decorations;
+    },
+  }
+);
+
+const indentPlugins = [
+  keymap.of([indentWithTab]),
+  indentUnit.of(" "),
+  indentService.of((context, pos) => {
+    const previousLine = context.lineAt(pos, -1).text;
+    if (previousLine.trim() === "") return null;
+    return /^[ \t]*/.exec(previousLine)?.[0]?.length ?? null;
+  }),
+  indentDecorationsPlugin,
+];
+
+export default indentPlugins;

app/syntax/quot.ts

@@ -11,7 +11,6 @@ export const quotLanguage = LRLanguage.define({
     props: [
       styleTags({
         Heading: t.heading,
-        Indent: t.separator,
         AutoLink: t.link,
         Code: t.monospace,
       }),
@@ -27,14 +26,6 @@ export const quotHighlighting = syntaxHighlighting(
       fontSize: "1.25em",
       marginBlockEnd: "0.5em",
     },
-    {
-      tag: t.separator,
-      letterSpacing: "1.5em",
-      "&:last-child:after": {
-        content: `"•"`,
-        marginInline: "-0.9em",
-      },
-    },
     {
       tag: t.link,
       class: "auto-link",

app/views/components/editor.tsx

@@ -1,11 +1,11 @@
 import { onCleanup, onMount } from "solid-js";
 import { minimalSetup } from "codemirror";
-import { emacsStyleKeymap, indentWithTab } from "@codemirror/commands";
+import { emacsStyleKeymap } from "@codemirror/commands";
-import { indentService, indentUnit } from "@codemirror/language";
 import { EditorView, keymap } from "@codemirror/view";
 import type Pages from "../../protocol/pages";
 import "./editor.css";
 import { quotHighlighting, quotLanguage } from "../../syntax/quot";
+import indentPlugins from "../../syntax/indent-plugins";
 
 export default (props: {
   id: number;
@@ -36,19 +36,11 @@ export default (props: {
           props.onUpdatePage({ id: props.id, title, text });
         }),
         EditorView.lineWrapping,
-        indentUnit.of(" "),
+        keymap.of(emacsStyleKeymap.filter(({ key }) => key !== "Ctrl-v")),
-        indentService.of((context, pos) => {
-          const previousLine = context.lineAt(pos, -1).text;
-          if (previousLine.trim() === "") return null;
-          return /^[ \t]*/.exec(previousLine)?.[0]?.length ?? null;
-        }),
-        keymap.of([
-          indentWithTab,
-          ...emacsStyleKeymap.filter(({ key }) => key !== "Ctrl-v"),
-        ]),
         minimalSetup,
         quotLanguage,
         quotHighlighting,
+        ...indentPlugins,
       ],
     });
     ref.addEventListener("click", (e) => {