feat: add @mermaid-js/parser package and info langium parser

.build/common.ts

@@ -2,6 +2,11 @@
  * Shared common options for both ESBuild and Vite
  */
 export const packageOptions = {
+  parser: {
+    name: 'mermaid-parser',
+    packageName: 'parser',
+    file: 'index.ts',
+  },
   mermaid: {
     name: 'mermaid',
     packageName: 'mermaid',

.build/generateLangium.ts

@@ -0,0 +1,5 @@
+import { generate } from 'langium-cli';
+
+export async function generateLangium() {
+  await generate({ file: `./packages/parser/langium-config.json` });
+}

.build/langium-cli.d.ts

@@ -0,0 +1,9 @@
+declare module 'langium-cli' {
+  export interface GenerateOptions {
+    file?: string;
+    mode?: 'development' | 'production';
+    watch?: boolean;
+  }
+
+  export function generate(options: GenerateOptions): Promise<boolean>;
+}

.esbuild/build.ts

@@ -2,6 +2,7 @@ import { build } from 'esbuild';
 import { mkdir, writeFile } from 'node:fs/promises';
 import { MermaidBuildOptions, defaultOptions, getBuildConfig } from './util.js';
 import { packageOptions } from '../.build/common.js';
+import { generateLangium } from '../.build/generateLangium.js';
 
 const shouldVisualize = process.argv.includes('--visualize');
 
@@ -52,9 +53,13 @@ const handler = (e) => {
 };
 
 const main = async () => {
+  await generateLangium();
   await mkdir('stats').catch(() => {});
   const packageNames = Object.keys(packageOptions) as (keyof typeof packageOptions)[];
-  await Promise.allSettled(packageNames.map((pkg) => buildPackage(pkg).catch(handler)));
+  // it should build `parser` before `mermaid` because it's a dependecy
+  for (const pkg of packageNames) {
+    await buildPackage(pkg).catch(handler);
+  }
 };
 
 void main();

.esbuild/server.ts

@@ -4,7 +4,11 @@ import cors from 'cors';
 import { getBuildConfig, defaultOptions } from './util.js';
 import { context } from 'esbuild';
 import chokidar from 'chokidar';
+import { generateLangium } from '../.build/generateLangium.js';
 
+const parserCtx = await context(
+  getBuildConfig({ ...defaultOptions, minify: false, core: false, entryName: 'parser' })
+);
 const mermaidCtx = await context(
   getBuildConfig({ ...defaultOptions, minify: false, core: false, entryName: 'mermaid' })
 );
@@ -28,7 +32,7 @@ const externalCtx = await context(
 const zenumlCtx = await context(
   getBuildConfig({ ...defaultOptions, minify: false, core: false, entryName: 'mermaid-zenuml' })
 );
-const contexts = [mermaidCtx, mermaidIIFECtx, externalCtx, zenumlCtx];
+const contexts = [parserCtx, mermaidCtx, mermaidIIFECtx, externalCtx, zenumlCtx];
 
 const rebuildAll = async () => {
   console.time('Rebuild time');
@@ -75,10 +79,11 @@ function sendEventsToAll() {
 }
 
 async function createServer() {
+  await generateLangium();
   handleFileChange();
   const app = express();
   chokidar
-    .watch('**/src/**/*.{js,ts,yaml,json}', {
+    .watch('**/src/**/*.{js,ts,langium,yaml,json}', {
       ignoreInitial: true,
       ignored: [/node_modules/, /dist/, /docs/, /coverage/],
     })
@@ -87,12 +92,16 @@ async function createServer() {
       if (!['add', 'change'].includes(event)) {
         return;
       }
+      if (/\.langium$/.test(path)) {
+        await generateLangium();
+      }
       console.log(`${path} changed. Rebuilding...`);
       handleFileChange();
     });
 
   app.use(cors());
   app.get('/events', eventsHandler);
+  app.use(express.static('./packages/parser/dist'));
   app.use(express.static('./packages/mermaid/dist'));
   app.use(express.static('./packages/mermaid-zenuml/dist'));
   app.use(express.static('./packages/mermaid-example-diagram/dist'));

.eslintignore

@@ -6,3 +6,6 @@ cypress/plugins/index.js
 coverage
 *.json
 node_modules
+
+# autogenereated by langium-cli
+generated/

.gitignore

@@ -47,3 +47,6 @@ stats/
 demos/dev/**
 !/demos/dev/example.html
 !/demos/dev/reload.js
+
+# autogenereated by langium-cli
+generated/

.prettierignore

@@ -10,3 +10,6 @@ stats
 .nyc_output
 # Autogenerated by `pnpm run --filter mermaid types:build-config`
 packages/mermaid/src/config.type.ts
+
+# autogenereated by langium-cli
+generated/

.vite/build.ts

@@ -8,6 +8,7 @@ import { visualizer } from 'rollup-plugin-visualizer';
 import type { TemplateType } from 'rollup-plugin-visualizer/dist/plugin/template-types.js';
 import istanbul from 'vite-plugin-istanbul';
 import { packageOptions } from '../.build/common.js';
+import { generateLangium } from '../.build/generateLangium.js';
 
 const visualize = process.argv.includes('--visualize');
 const watch = process.argv.includes('--watch');
@@ -82,7 +83,7 @@ export const getBuildConfig = ({ minify, core, watch, entryName }: BuildOptions)
       // @ts-expect-error According to the type definitions, rollup plugins are incompatible with vite
       typescript({ compilerOptions: { declaration: false } }),
       istanbul({
-        exclude: ['node_modules', 'test/', '__mocks__'],
+        exclude: ['node_modules', 'test/', '__mocks__', 'generated'],
         extension: ['.js', '.ts'],
         requireEnv: true,
         forceBuildInstrument: coverage,
@@ -106,18 +107,24 @@ const buildPackage = async (entryName: keyof typeof packageOptions) => {
 
 const main = async () => {
   const packageNames = Object.keys(packageOptions) as (keyof typeof packageOptions)[];
-  for (const pkg of packageNames.filter((pkg) => !mermaidOnly || pkg === 'mermaid')) {
+  for (const pkg of packageNames.filter(
+    (pkg) => !mermaidOnly || pkg === 'mermaid' || pkg === 'parser'
+  )) {
     await buildPackage(pkg);
   }
 };
 
+await generateLangium();
+
 if (watch) {
+  await build(getBuildConfig({ minify: false, watch, core: false, entryName: 'parser' }));
   build(getBuildConfig({ minify: false, watch, core: false, entryName: 'mermaid' }));
   if (!mermaidOnly) {
     build(getBuildConfig({ minify: false, watch, entryName: 'mermaid-example-diagram' }));
     build(getBuildConfig({ minify: false, watch, entryName: 'mermaid-zenuml' }));
   }
 } else if (visualize) {
+  await build(getBuildConfig({ minify: false, watch, core: false, entryName: 'parser' }));
   await build(getBuildConfig({ minify: false, core: true, entryName: 'mermaid' }));
   await build(getBuildConfig({ minify: false, core: false, entryName: 'mermaid' }));
 } else {

.vite/server.ts

@@ -14,6 +14,7 @@ async function createServer() {
   });
 
   app.use(cors());
+  app.use(express.static('./packages/parser/dist'));
   app.use(express.static('./packages/mermaid/dist'));
   app.use(express.static('./packages/mermaid-zenuml/dist'));
   app.use(express.static('./packages/mermaid-example-diagram/dist'));

cSpell.json

@@ -71,6 +71,7 @@
     "knut",
     "knutsveidqvist",
     "laganeckas",
+    "langium",
     "linetype",
     "lintstagedrc",
     "logmsg",

package.json

@@ -15,11 +15,11 @@
     "git graph"
   ],
   "scripts": {
-    "build": "pnpm run -r clean && pnpm build:esbuild && pnpm build:types",
+    "build": "pnpm build:esbuild && pnpm build:types",
     "build:esbuild": "pnpm run -r clean && ts-node-esm --transpileOnly .esbuild/build.ts",
     "build:mermaid": "pnpm build:esbuild --mermaid",
     "build:viz": "pnpm build:esbuild --visualize",
-    "build:types": "tsc -p ./packages/mermaid/tsconfig.json --emitDeclarationOnly && tsc -p ./packages/mermaid-zenuml/tsconfig.json --emitDeclarationOnly && tsc -p ./packages/mermaid-example-diagram/tsconfig.json --emitDeclarationOnly",
+    "build:types": "tsc -p ./packages/parser/tsconfig.json --emitDeclarationOnly && tsc -p ./packages/mermaid/tsconfig.json --emitDeclarationOnly && tsc -p ./packages/mermaid-zenuml/tsconfig.json --emitDeclarationOnly && tsc -p ./packages/mermaid-example-diagram/tsconfig.json --emitDeclarationOnly",
     "dev": "ts-node-esm --transpileOnly .esbuild/server.ts",
     "dev:vite": "ts-node-esm --transpileOnly .vite/server.ts",
     "dev:coverage": "pnpm coverage:cypress:clean && VITE_COVERAGE=true pnpm dev:vite",
@@ -107,6 +107,7 @@
     "jison": "^0.4.18",
     "js-yaml": "^4.1.0",
     "jsdom": "^22.0.0",
+    "langium-cli": "2.0.1",
     "lint-staged": "^13.2.1",
     "nyc": "^15.1.0",
     "path-browserify": "^1.0.1",

packages/mermaid-zenuml/src/parser.ts

@@ -5,7 +5,6 @@
  * This is a dummy parser that satisfies the mermaid API logic.
  */
 export default {
-  parser: { yy: {} },
   parse: () => {
     // no op
   },

packages/mermaid/package.json

@@ -72,6 +72,7 @@
     "khroma": "^2.0.0",
     "lodash-es": "^4.17.21",
     "mdast-util-from-markdown": "^1.3.0",
+    "mermaid-parser": "workspace:^",
     "stylis": "^4.1.3",
     "ts-dedent": "^2.2.0",
     "uuid": "^9.0.0"

packages/mermaid/src/Diagram.ts

@@ -50,7 +50,10 @@ export class Diagram {
     this.parser.parse = (text: string) =>
       originalParse(cleanupComments(extractFrontMatter(text, this.db, configApi.addDirective)));
 
-    this.parser.parser.yy = this.db;
+    if (this.parser.parser !== undefined) {
+      // The parser.parser.yy is only present in JISON parsers. So, we'll only set if required.
+      this.parser.parser.yy = this.db;
+    }
     this.init = diagram.init;
     this.parse();
   }

packages/mermaid/src/diagram-api/diagram-orchestration.ts

@@ -45,7 +45,6 @@ export const addDiagrams = () => {
       styles: {}, // should never be used
       renderer: {}, // should never be used
       parser: {
-        parser: { yy: {} },
         parse: () => {
           throw new Error(
             'Diagrams beginning with --- are not valid. ' +

packages/mermaid/src/diagram-api/diagramAPI.spec.ts

@@ -39,7 +39,6 @@ describe('DiagramAPI', () => {
           parse: (_text) => {
             return;
           },
-          parser: { yy: {} },
         },
         renderer: {},
         styles: {},

packages/mermaid/src/diagram-api/types.ts

@@ -80,7 +80,7 @@ export type DrawDefinition = (
 
 export interface ParserDefinition {
   parse: (text: string) => void;
-  parser: { yy: DiagramDB };
+  parser?: { yy: DiagramDB };
 }
 
 /**

packages/mermaid/src/diagram.spec.ts

@@ -30,9 +30,6 @@ describe('diagram detection', () => {
               parse: () => {
                 // no-op
               },
-              parser: {
-                yy: {},
-              },
             },
             renderer: {},
             styles: {},

packages/mermaid/src/diagrams/common/populateCommonDb.ts

@@ -0,0 +1,15 @@
+import type { DiagramAST } from 'mermaid-parser';
+
+import type { DiagramDB } from '../../diagram-api/types.js';
+
+export function populateCommonDb(ast: DiagramAST, db: DiagramDB) {
+  if (ast.accDescr) {
+    db.setAccDescription?.(ast.accDescr);
+  }
+  if (ast.accTitle) {
+    db.setAccTitle?.(ast.accTitle);
+  }
+  if (ast.title) {
+    db.setDiagramTitle?.(ast.title);
+  }
+}

packages/mermaid/src/diagrams/error/errorDiagram.ts

@@ -5,7 +5,6 @@ const diagram: DiagramDefinition = {
   db: {},
   renderer,
   parser: {
-    parser: { yy: {} },
     parse: (): void => {
       return;
     },

packages/mermaid/src/diagrams/info/info.spec.ts

@@ -1,24 +1,31 @@
-// @ts-ignore - jison doesn't export types
-import { parser } from './parser/info.jison';
-import { db } from './infoDb.js';
-
-describe('info diagram', () => {
-  beforeEach(() => {
-    parser.yy = db;
-    parser.yy.clear();
-  });
+import { parser } from './infoParser.js';
 
+describe('info', () => {
   it('should handle an info definition', () => {
     const str = `info`;
-    parser.parse(str);
-
-    expect(db.getInfo()).toBeFalsy();
+    expect(() => {
+      parser.parse(str);
+    }).not.toThrow();
   });
 
   it('should handle an info definition with showInfo', () => {
     const str = `info showInfo`;
-    parser.parse(str);
+    expect(() => {
+      parser.parse(str);
+    }).not.toThrow();
+  });
+
+  it('should throw because of unsupported info grammar', () => {
+    const str = `info unsupported`;
+    expect(() => {
+      parser.parse(str);
+    }).toThrow('Parsing failed: unexpected character: ->u<- at offset: 5, skipped 11 characters.');
+  });
 
-    expect(db.getInfo()).toBeTruthy();
+  it('should throw because of unsupported info grammar', () => {
+    const str = `info unsupported`;
+    expect(() => {
+      parser.parse(str);
+    }).toThrow('Parsing failed: unexpected character: ->u<- at offset: 5, skipped 11 characters.');
   });
 });

packages/mermaid/src/diagrams/info/infoDb.ts

@@ -1,23 +1,10 @@
 import type { InfoFields, InfoDB } from './infoTypes.js';
+import { version } from '../../../package.json';
 
-export const DEFAULT_INFO_DB: InfoFields = {
-  info: false,
-} as const;
+export const DEFAULT_INFO_DB: InfoFields = { version } as const;
 
-let info: boolean = DEFAULT_INFO_DB.info;
-
-export const setInfo = (toggle: boolean): void => {
-  info = toggle;
-};
-
-export const getInfo = (): boolean => info;
-
-const clear = (): void => {
-  info = DEFAULT_INFO_DB.info;
-};
+export const getVersion = (): string => DEFAULT_INFO_DB.version;
 
 export const db: InfoDB = {
-  clear,
-  setInfo,
-  getInfo,
+  getVersion,
 };

packages/mermaid/src/diagrams/info/infoDiagram.ts

@@ -1,6 +1,5 @@
 import type { DiagramDefinition } from '../../diagram-api/types.js';
-// @ts-ignore - jison doesn't export types
-import parser from './parser/info.jison';
+import { parser } from './infoParser.js';
 import { db } from './infoDb.js';
 import { renderer } from './infoRenderer.js';
 

packages/mermaid/src/diagrams/info/infoParser.ts

@@ -0,0 +1,12 @@
+import type { Info } from 'mermaid-parser';
+import { parse } from 'mermaid-parser';
+
+import { log } from '../../logger.js';
+import type { ParserDefinition } from '../../diagram-api/types.js';
+
+export const parser: ParserDefinition = {
+  parse: (input: string): void => {
+    const ast: Info = parse('info', input);
+    log.debug(ast);
+  },
+};

packages/mermaid/src/diagrams/info/infoTypes.ts

@@ -1,11 +1,9 @@
 import type { DiagramDB } from '../../diagram-api/types.js';
 
 export interface InfoFields {
-  info: boolean;
+  version: string;
 }
 
 export interface InfoDB extends DiagramDB {
-  clear: () => void;
-  setInfo: (info: boolean) => void;
-  getInfo: () => boolean;
+  getVersion: () => string;
 }