Fix blank line rendering.

packages/js/core/dist/parser.cjs

@@ -1 +1 @@
-"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});function f(e="",r=" "){return{line:e,indent:r,type:0,level:0,offsetHead:0,offsetTail:0}}function o(e){if(typeof e!="object"||!e||typeof e.type!="number"||typeof e.level!="number")throw new Error("'lineData' must be an object with 'line' string, and 'type' and 'level' integer properties");if(typeof e.indent!="string"||e.indent.length===0||e.indent.length>1)throw new Error("'lineData.indent' must be a single-character string");if(typeof e.line!="string")throw new Error("'lineData.line' must be a string");let r=0,t=0;if(!e.line.length)e.type===1&&(t+=1),e.type===0&&(t=e.level),e.type=r,e.level=t,e.offsetHead=0,e.offsetTail=0;else{for(r=1;e.line[t]===e.indent&&t<=e.level+1;)++t;for(e.type=r,e.level=t,e.offsetHead=t,e.offsetTail=t;e.line[e.offsetTail]&&e.line[e.offsetTail]!==" ";)++e.offsetTail}return e}exports.createLineData=f;exports.parseLine=o;
+"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});function f(e="",r=" "){return{line:e,indent:r,type:0,level:0,offsetHead:0,offsetTail:0}}function o(e){if(typeof e!="object"||!e||typeof e.type!="number"||typeof e.level!="number")throw new Error("'lineData' must be an object with 'line' string, and 'type' and 'level' integer properties");if(typeof e.indent!="string"||e.indent.length===0||e.indent.length>1)throw new Error("'lineData.indent' must be a single-character string");if(typeof e.line!="string")throw new Error("'lineData.line' must be a string");let r=0,t=0;if(!e.line.length)e.type===1&&(t=e.level+1),e.type===0&&(t=e.level),e.type=r,e.level=t,e.offsetHead=0,e.offsetTail=0;else{for(r=1;e.line[t]===e.indent&&t<=e.level+1;)++t;for(e.type=r,e.level=t,e.offsetHead=t,e.offsetTail=t;e.line[e.offsetTail]&&e.line[e.offsetTail]!==" ";)++e.offsetTail}return e}exports.createLineData=f;exports.parseLine=o;

packages/js/core/dist/parser.js

@@ -10,7 +10,7 @@ function o(e) {
     throw new Error("'lineData.line' must be a string");
   let r = 0, f = 0;
   if (!e.line.length)
-    e.type === 1 && (f += 1), e.type === 0 && (f = e.level), e.type = r, e.level = f, e.offsetHead = 0, e.offsetTail = 0;
+    e.type === 1 && (f = e.level + 1), e.type === 0 && (f = e.level), e.type = r, e.level = f, e.offsetHead = 0, e.offsetTail = 0;
   else {
     for (r = 1; e.line[f] === e.indent && f <= e.level + 1; )
       ++f;

packages/js/core/src/parser.ts

@@ -1,3 +1,8 @@
+enum LineType {
+  BLANK,
+  NORMAL,
+}
+
 export type LineData = {
   line: string;
   indent: string;
@@ -16,19 +21,21 @@ export function parseLine(lineData: LineData): LineData {
   if (typeof lineData.indent !== 'string' || lineData.indent.length === 0 || lineData.indent.length > 1) throw new Error(`'lineData.indent' must be a single-character string`)
   if (typeof lineData.line !== 'string') throw new Error(`'lineData.line' must be a string`)
 
-  let type = 0
+  let type = LineType.BLANK
   let level = 0
 
   if (!lineData.line.length) {
-    if (lineData.type === 1) level += 1
+    // TODO: Not sure if this is necessary. If the previous line was a normal line, it makes the blank line a child of the normal line.
-    if (lineData.type === 0) level = lineData.level
+    // If the previous line was a blank line, the blank line retains the same level.
+    if (lineData.type === LineType.NORMAL) level = lineData.level + 1
+    if (lineData.type === LineType.BLANK) level = lineData.level
 
     lineData.type = type
     lineData.level = level
     lineData.offsetHead = 0
     lineData.offsetTail = 0
   } else {
-    type = 1
+    type = LineType.NORMAL
 
     while (lineData.line[level] === lineData.indent && level <= lineData.level + 1) ++level
     lineData.type = type