Merge branch 'develop' into 6777-er-relationship-label-optional

on-behalf-of: @Mermaid-Chart <hello@mermaidchart.com>

.changeset/angry-trains-fall.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: Make relationship-label optional in ER diagrams

.changeset/big-tools-do.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Handle master/main merges correctly in GitGraph diagrams

.changeset/brave-baths-behave.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: Prevent HTML tags from being escaped in sandbox label rendering

.changeset/ten-plums-bet.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: Support ComponentQueue_Ext to prevent parsing error

cypress/helpers/util.ts

@@ -98,12 +98,21 @@ export const openURLAndVerifyRendering = (
 
   cy.visit(url);
   cy.window().should('have.property', 'rendered', true);
-  cy.get('svg').should('be.visible');
-  // cspell:ignore viewbox
-  cy.get('svg').should('not.have.attr', 'viewbox');
 
-  if (validation) {
-    cy.get('svg').should(validation);
+  // Handle sandbox mode where SVG is inside an iframe
+  if (options.securityLevel === 'sandbox') {
+    cy.get('iframe').should('be.visible');
+    if (validation) {
+      cy.get('iframe').should(validation);
+    }
+  } else {
+    cy.get('svg').should('be.visible');
+    // cspell:ignore viewbox
+    cy.get('svg').should('not.have.attr', 'viewbox');
+
+    if (validation) {
+      cy.get('svg').should(validation);
+    }
   }
 
   if (screenshot) {

cypress/integration/rendering/c4.spec.js

@@ -114,4 +114,28 @@ describe('C4 diagram', () => {
       {}
     );
   });
+  it('C4.6 should render C4Context diagram with ComponentQueue_Ext', () => {
+    imgSnapshotTest(
+      `
+      C4Context
+      title System Context diagram with ComponentQueue_Ext
+
+      Enterprise_Boundary(b0, "BankBoundary0") {
+          Person(customerA, "Banking Customer A", "A customer of the bank, with personal bank accounts.")
+
+          System(SystemAA, "Internet Banking System", "Allows customers to view information about their bank accounts, and make payments.")
+
+          Enterprise_Boundary(b1, "BankBoundary") {
+            ComponentQueue_Ext(msgQueue, "Message Queue", "RabbitMQ", "External message queue system for processing banking transactions")
+            System_Ext(SystemC, "E-mail system", "The internal Microsoft Exchange e-mail system.")
+          }
+        }
+
+      BiRel(customerA, SystemAA, "Uses")
+      Rel(SystemAA, msgQueue, "Sends messages to")
+      Rel(SystemAA, SystemC, "Sends e-mails", "SMTP")
+      `,
+      {}
+    );
+  });
 });

cypress/integration/rendering/erDiagram.spec.js

@@ -322,6 +322,18 @@ ORDER ||--|{ LINE-ITEM : contains
     );
   });
 
+  it('should render an ER diagram  without labels also', () => {
+    imgSnapshotTest(
+      `
+    erDiagram
+        BOOK }|..|{ AUTHOR 
+        BOOK }|..|{ GENRE
+        AUTHOR }|..|{ GENRE 
+      `,
+      { logLevel: 1 }
+    );
+  });
+
   it('should render relationship labels with line breaks', () => {
     imgSnapshotTest(
       `

cypress/integration/rendering/flowchart-v2.spec.js

@@ -79,6 +79,18 @@ describe('Flowchart v2', () => {
       { htmlLabels: true, flowchart: { htmlLabels: true }, securityLevel: 'loose' }
     );
   });
+  it('6a: should render complex HTML in labels with sandbox security', () => {
+    imgSnapshotTest(
+      `flowchart TD
+    A[Christmas] -->|Get money| B(Go shopping)
+    B --> C{Let me think}
+    C -->|One| D[Laptop]
+    C -->|Two| E[iPhone]
+    C -->|Three| F[fa:fa-car Car]
+      `,
+      { securityLevel: 'sandbox', flowchart: { htmlLabels: true } }
+    );
+  });
   it('7: should render a flowchart when useMaxWidth is true (default)', () => {
     renderGraph(
       `flowchart TD

cypress/integration/rendering/gitGraph.spec.js

@@ -1569,14 +1569,4 @@ gitGraph TB:
       {}
     );
   });
-  it('77: should render a gitGraph merging main into a newly created branch', () => {
-    imgSnapshotTest(
-      `gitGraph
-    commit
-    branch stable
-    checkout stable
-    merge main`,
-      {}
-    );
-  });
 });

docs/syntax/entityRelationshipDiagram.md

@@ -135,6 +135,44 @@ erDiagram
     "This **is** _Markdown_"
 ```
 
+#### Optional Relationship Labels (v\<MERMAID_RELEASE_VERSION>+)
+
+The relationship label in ER diagrams is optional. You can define relationships without specifying a label, and the diagram will render correctly.
+
+For example, the following is valid:
+
+```mermaid-example
+erDiagram
+    BOOK }|..|{ AUTHOR
+    BOOK }|..|{ GENRE
+    AUTHOR }|..|{ GENRE
+```
+
+```mermaid
+erDiagram
+    BOOK }|..|{ AUTHOR
+    BOOK }|..|{ GENRE
+    AUTHOR }|..|{ GENRE
+```
+
+This will show the relationships between the entities without any labels on the connecting lines.
+
+You can still add a label if you want to describe the relationship:
+
+```mermaid-example
+erDiagram
+    BOOK }|..|{ AUTHOR : written_by
+    BOOK }|..|{ GENRE : categorized_as
+    AUTHOR }|..|{ GENRE : specializes_in
+```
+
+```mermaid
+erDiagram
+    BOOK }|..|{ AUTHOR : written_by
+    BOOK }|..|{ GENRE : categorized_as
+    AUTHOR }|..|{ GENRE : specializes_in
+```
+
 ### Relationship Syntax
 
 The `relationship` part of each statement can be broken down into three sub-components:

package.json

@@ -63,8 +63,8 @@
     ]
   },
   "devDependencies": {
-    "@applitools/eyes-cypress": "^3.55.4",
-    "@argos-ci/cypress": "^6.1.5",
+    "@applitools/eyes-cypress": "^3.56.3",
+    "@argos-ci/cypress": "^6.2.1",
     "@changesets/changelog-github": "^0.5.1",
     "@changesets/cli": "^2.29.7",
     "@cspell/eslint-plugin": "^9.3.0",
@@ -77,7 +77,7 @@
     "@types/jsdom": "^21.1.7",
     "@types/lodash": "^4.17.20",
     "@types/mdast": "^4.0.4",
-    "@types/node": "^22.18.13",
+    "@types/node": "^22.19.0",
     "@types/rollup-plugin-visualizer": "^5.0.3",
     "@vitest/coverage-v8": "^3.2.4",
     "@vitest/spy": "^3.2.4",
@@ -88,7 +88,7 @@
     "cors": "^2.8.5",
     "cpy-cli": "^5.0.0",
     "cross-env": "^7.0.3",
-    "cspell": "^9.2.2",
+    "cspell": "^9.3.0",
     "cypress": "^14.5.4",
     "cypress-image-snapshot": "^4.0.1",
     "cypress-split": "^1.24.25",
@@ -127,7 +127,7 @@
     "tsx": "^4.20.6",
     "typescript": "~5.7.3",
     "typescript-eslint": "^8.38.0",
-    "vite": "^7.0.7",
+    "vite": "^7.0.8",
     "vite-plugin-istanbul": "^7.0.0",
     "vitest": "^3.2.4"
   },

packages/mermaid/package.json

@@ -78,7 +78,7 @@
     "d3-sankey": "^0.12.3",
     "dagre-d3-es": "7.0.13",
     "dayjs": "^1.11.19",
-    "dompurify": "^3.2.7",
+    "dompurify": "^3.3.0",
     "katex": "^0.16.25",
     "khroma": "^2.1.0",
     "lodash-es": "^4.17.21",

packages/mermaid/src/diagrams/c4/parser/c4Component.spec.js

@@ -0,0 +1,58 @@
+import c4Db from '../c4Db.js';
+import c4 from './c4Diagram.jison';
+import { setConfig } from '../../../config.js';
+
+setConfig({
+  securityLevel: 'strict',
+});
+
+describe.each([
+  ['Component', 'component'],
+  ['ComponentDb', 'component_db'],
+  ['ComponentQueue', 'component_queue'],
+  ['Component_Ext', 'external_component'],
+  ['ComponentDb_Ext', 'external_component_db'],
+  ['ComponentQueue_Ext', 'external_component_queue'],
+])('parsing a C4 %s', function (macroName, elementName) {
+  beforeEach(function () {
+    c4.parser.yy = c4Db;
+    c4.parser.yy.clear();
+  });
+
+  it('should parse a C4 diagram with one Component correctly', function () {
+    c4.parser.parse(`C4Component
+title Component diagram for Internet Banking Component
+${macroName}(ComponentAA, "Internet Banking Component", "Technology", "Allows customers to view information about their bank accounts, and make payments.")`);
+
+    const yy = c4.parser.yy;
+
+    const shapes = yy.getC4ShapeArray();
+    expect(shapes.length).toBe(1);
+    const onlyShape = shapes[0];
+
+    expect(onlyShape).toMatchObject({
+      alias: 'ComponentAA',
+      descr: {
+        text: 'Allows customers to view information about their bank accounts, and make payments.',
+      },
+      label: {
+        text: 'Internet Banking Component',
+      },
+      techn: {
+        text: 'Technology',
+      },
+      typeC4Shape: {
+        text: elementName,
+      },
+    });
+  });
+
+  it('should handle a trailing whitespaces after Component', function () {
+    const whitespace = ' ';
+    const rendered = c4.parser.parse(`C4Component${whitespace}
+title Component diagram for Internet Banking Component${whitespace}
+${macroName}(ComponentAA, "Internet Banking Component", "Technology", "Allows customers to view information about their bank accounts, and make payments.")${whitespace}`);
+
+    expect(rendered).toBe(true);
+  });
+});

packages/mermaid/src/diagrams/c4/parser/c4Diagram.jison

@@ -158,10 +158,10 @@ accDescr\s*"{"\s*                         { this.begin("acc_descr_multiline");}
 "UpdateRelStyle"                          { this.begin("update_rel_style"); return 'UPDATE_REL_STYLE';}
 "UpdateLayoutConfig"                      { this.begin("update_layout_config"); return 'UPDATE_LAYOUT_CONFIG';}
 
-<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config><<EOF>>                return "EOF_IN_STRUCT";
-<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config>[(][ ]*[,]             { this.begin("attribute"); return "ATTRIBUTE_EMPTY";}
-<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config>[(]                    { this.begin("attribute"); }
-<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config,attribute>[)]          { this.popState();this.popState();}
+<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext_queue,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config><<EOF>>                return "EOF_IN_STRUCT";
+<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext_queue,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config>[(][ ]*[,]             { this.begin("attribute"); return "ATTRIBUTE_EMPTY";}
+<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext_queue,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config>[(]                    { this.begin("attribute"); }
+<person,person_ext,system_ext_queue,system_ext_db,system_ext,system_queue,system_db,system,boundary,enterprise_boundary,system_boundary,container_ext_db,container_ext_queue,container_ext,container_queue,container_db,container,container_boundary,component_ext_db,component_ext_queue,component_ext,component_queue,component_db,component,node,node_l,node_r,rel,birel,rel_u,rel_d,rel_l,rel_r,rel_b,rel_index,update_el_style,update_rel_style,update_layout_config,attribute>[)]          { this.popState();this.popState();}
 
 <attribute>",,"                           { return 'ATTRIBUTE_EMPTY';}
 <attribute>","                            { }

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

@@ -70,6 +70,31 @@ describe('Sanitize text', () => {
     });
     expect(result).not.toContain('javascript:alert(1)');
   });
+
+  it('should allow HTML tags in sandbox mode', () => {
+    const htmlStr = '<p>This is a <strong>bold</strong> text</p>';
+    const result = sanitizeText(htmlStr, {
+      securityLevel: 'sandbox',
+      flowchart: { htmlLabels: true },
+    });
+    expect(result).toContain('<p>');
+    expect(result).toContain('<strong>');
+    expect(result).toContain('</strong>');
+    expect(result).toContain('</p>');
+  });
+
+  it('should remove script tags in sandbox mode', () => {
+    const maliciousStr = '<p>Hello <script>alert(1)</script> world</p>';
+    const result = sanitizeText(maliciousStr, {
+      securityLevel: 'sandbox',
+      flowchart: { htmlLabels: true },
+    });
+    expect(result).not.toContain('<script>');
+    expect(result).not.toContain('alert(1)');
+    expect(result).toContain('<p>');
+    expect(result).toContain('Hello');
+    expect(result).toContain('world');
+  });
 });
 
 describe('generic parser', () => {

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

@@ -66,7 +66,7 @@ export const removeScript = (txt: string): string => {
 const sanitizeMore = (text: string, config: MermaidConfig) => {
   if (config.flowchart?.htmlLabels !== false) {
     const level = config.securityLevel;
-    if (level === 'antiscript' || level === 'strict') {
+    if (level === 'antiscript' || level === 'strict' || level === 'sandbox') {
       text = removeScript(text);
     } else if (level !== 'loose') {
       text = breakToPlaceholder(text);

packages/mermaid/src/diagrams/er/parser/erDiagram.jison

@@ -99,6 +99,22 @@ start
     : 'ER_DIAGRAM' document 'EOF' { /*console.log('finished parsing');*/ }
     ;
 
+relationship
+  : ENTITY relationType ENTITY maybeRole
+    {
+      yy.addRelationship($1, $4, $3, $2);
+    };
+
+maybeRole
+  : COLON role
+    {
+      $$ = $2;
+    }
+  | /* empty */
+    {
+      $$ = '';
+    };
+
 document
 	: /* empty */ { $$ = [] }
 	| document line {$1.push($2);$$ = $1}
@@ -113,32 +129,34 @@ line
 
 
 statement
-    : entityName relSpec entityName COLON role
+    : entityName relSpec entityName maybeRole
       {
           yy.addEntity($1);
           yy.addEntity($3);
-          yy.addRelationship($1, $5, $3, $2);
+          yy.addRelationship($1, $4, $3, $2);
       }
-    | entityName STYLE_SEPARATOR idList relSpec entityName STYLE_SEPARATOR idList COLON role
+    | entityName STYLE_SEPARATOR idList relSpec entityName STYLE_SEPARATOR idList maybeRole
+
       {
           yy.addEntity($1);
           yy.addEntity($5);
-          yy.addRelationship($1, $9, $5, $4);
+          yy.addRelationship($1, $8, $5, $4);
           yy.setClass([$1], $3);
           yy.setClass([$5], $7);
       }
-    | entityName STYLE_SEPARATOR idList relSpec entityName COLON role
+    | entityName STYLE_SEPARATOR idList relSpec entityName maybeRole
+
       {
           yy.addEntity($1);
           yy.addEntity($5);
-          yy.addRelationship($1, $7, $5, $4);
+          yy.addRelationship($1, $6, $5, $4);
           yy.setClass([$1], $3);
       }
-    | entityName relSpec entityName STYLE_SEPARATOR idList COLON role
+    | entityName relSpec entityName STYLE_SEPARATOR idList maybeRole
       {
           yy.addEntity($1);
           yy.addEntity($3);
-          yy.addRelationship($1, $7, $3, $2);
+          yy.addRelationship($1, $6, $3, $2);
           yy.setClass([$3], $5);
       }
     | entityName BLOCK_START attributes BLOCK_STOP

packages/mermaid/src/diagrams/er/parser/erDiagram.spec.js

@@ -981,6 +981,12 @@ describe('when parsing ER diagram it...', function () {
       expect(rels[0].roleA).toBe('places');
     });
 
+    it('should allow label as optional', function () {
+      erDiagram.parser.parse('erDiagram\nCUSTOMER ||--|{ ORDER');
+      const rels = erDb.getRelationships();
+      expect(rels[0].roleA).toBe('');
+    });
+
     it('should represent parent-child relationship correctly', function () {
       erDiagram.parser.parse('erDiagram\nPROJECT u--o{ TEAM_MEMBER : "parent"');
       const rels = erDb.getRelationships();
@@ -989,6 +995,20 @@ describe('when parsing ER diagram it...', function () {
       expect(rels[0].relSpec.cardB).toBe(erDb.Cardinality.MD_PARENT);
       expect(rels[0].relSpec.cardA).toBe(erDb.Cardinality.ZERO_OR_MORE);
     });
+
+    it('should handle whitespace-only relationship labels', function () {
+      erDiagram.parser.parse('erDiagram\nBOOK }|..|{ AUTHOR : "   "');
+      let rels = erDb.getRelationships();
+      expect(rels[rels.length - 1].roleA).toBe('   ');
+
+      erDiagram.parser.parse('erDiagram\nBOOK }|..|{ GENRE : "\t"');
+      rels = erDb.getRelationships();
+      expect(rels[rels.length - 1].roleA).toBe('\t');
+
+      erDiagram.parser.parse('erDiagram\nAUTHOR }|..|{ GENRE : "      "');
+      rels = erDb.getRelationships();
+      expect(rels[rels.length - 1].roleA).toBe('      ');
+    });
   });
 
   describe('prototype properties', function () {

packages/mermaid/src/diagrams/git/gitGraph.spec.ts

@@ -1,7 +1,6 @@
 import { log } from '../../logger.js';
 import { db } from './gitGraphAst.js';
 import { parser } from './gitGraphParser.js';
-import { commitType } from './gitGraphTypes.js';
 
 describe('when parsing a gitGraph', function () {
   beforeEach(function () {
@@ -844,39 +843,6 @@ describe('when parsing a gitGraph', function () {
       expect(db.getBranchesAsObjArray()).toStrictEqual([{ name: 'main' }, { name: 'testBranch' }]);
     });
 
-    it('should handle merging the same branch multiple times', async () => {
-      const str = `gitGraph:
-        commit
-        branch stable
-        checkout stable
-        merge main
-        checkout main
-        commit
-        commit
-        checkout stable
-        merge main
-        `;
-
-      await parser.parse(str);
-      const commits = db.getCommits();
-      expect(commits.size).toBe(5);
-      expect(db.getCurrentBranch()).toBe('stable');
-      expect(db.getDirection()).toBe('LR');
-      expect(db.getBranches().size).toBe(2);
-
-      const commitsArray = db.getCommitsArray();
-      expect(commitsArray[0].branch).toBe('main');
-      expect(commitsArray[0].parents).toStrictEqual([]);
-      expect(commitsArray[1].branch).toBe('stable');
-      expect(commitsArray[1].type).toBe(commitType.MERGE);
-      expect(commitsArray[1].parents.length).toBe(2);
-      expect(commitsArray[2].branch).toBe('main');
-      expect(commitsArray[3].branch).toBe('main');
-      expect(commitsArray[4].branch).toBe('stable');
-      expect(commitsArray[4].type).toBe(commitType.MERGE);
-      expect(commitsArray[4].parents.length).toBe(2);
-    });
-
     it('should handle merge with custom ids, tags and type', async () => {
       const str = `gitGraph:
           commit
@@ -1270,7 +1236,7 @@ describe('when parsing a gitGraph', function () {
         );
       }
     });
-    it('should allow merging branches having same heads', async () => {
+    it('should throw error when trying to merge branches having same heads', async () => {
       const str = `gitGraph
         commit
         branch testBranch
@@ -1278,19 +1244,13 @@ describe('when parsing a gitGraph', function () {
         merge testBranch
         `;
 
-      await parser.parse(str);
-      const commits = db.getCommits();
-      expect(commits.size).toBe(2);
-      expect(db.getCurrentBranch()).toBe('main');
-
-      const commitsArray = db.getCommitsArray();
-      expect(commitsArray[0].branch).toBe('main');
-      expect(commitsArray[0].parents).toStrictEqual([]);
-      expect(commitsArray[1].branch).toBe('main');
-      expect(commitsArray[1].type).toBe(commitType.MERGE);
-      expect(commitsArray[1].parents.length).toBe(2);
-      expect(commitsArray[1].parents[0]).toBe(commitsArray[0].id);
-      expect(commitsArray[1].parents[1]).toBe(commitsArray[0].id);
+      try {
+        await parser.parse(str);
+        // Fail test if above expression doesn't throw anything.
+        expect(true).toBe(false);
+      } catch (e: any) {
+        expect(e.message).toBe('Incorrect usage of "merge". Both branches have same head');
+      }
     });
     it('should throw error when trying to merge branch which has no commits', async () => {
       const str = `gitGraph

packages/mermaid/src/diagrams/git/gitGraphAst.ts

@@ -167,6 +167,9 @@ export const merge = (mergeDB: MergeDB): void => {
   const otherCommit: Commit | undefined = otherBranchCheck
     ? state.records.commits.get(otherBranchCheck)
     : undefined;
+  if (currentCommit && otherCommit && currentCommit.branch === otherBranch) {
+    throw new Error(`Cannot merge branch '${otherBranch}' into itself.`);
+  }
   if (state.records.currBranch === otherBranch) {
     const error: any = new Error('Incorrect usage of "merge". Cannot merge a branch to itself');
     error.hash = {
@@ -209,6 +212,15 @@ export const merge = (mergeDB: MergeDB): void => {
     };
     throw error;
   }
+  if (currentCommit === otherCommit) {
+    const error: any = new Error('Incorrect usage of "merge". Both branches have same head');
+    error.hash = {
+      text: `merge ${otherBranch}`,
+      token: `merge ${otherBranch}`,
+      expected: ['branch abc'],
+    };
+    throw error;
+  }
   if (customId && state.records.commits.has(customId)) {
     const error: any = new Error(
       'Incorrect usage of "merge". Commit with id:' +

packages/mermaid/src/docs/package.json

@@ -21,19 +21,19 @@
     "font-awesome": "^4.7.0",
     "jiti": "^2.4.2",
     "mermaid": "workspace:^",
-    "vue": "^3.5.23"
+    "vue": "^3.5.24"
   },
   "devDependencies": {
     "@iconify-json/carbon": "^1.2.14",
-    "@unocss/reset": "^66.5.4",
+    "@unocss/reset": "^66.5.5",
     "@vite-pwa/vitepress": "^1.0.1",
     "@vitejs/plugin-vue": "^6.0.1",
     "fast-glob": "^3.3.3",
     "https-localhost": "^4.7.1",
     "pathe": "^2.0.3",
-    "unocss": "^66.5.4",
+    "unocss": "^66.5.5",
     "unplugin-vue-components": "^28.8.0",
-    "vite": "^7.0.7",
+    "vite": "^7.0.8",
     "vite-plugin-pwa": "^1.0.3",
     "vitepress": "1.6.4",
     "workbox-window": "^7.3.0"

packages/mermaid/src/docs/syntax/entityRelationshipDiagram.md

@@ -89,6 +89,30 @@ erDiagram
     "This **is** _Markdown_"
 ```
 
+#### Optional Relationship Labels (v<MERMAID_RELEASE_VERSION>+)
+
+The relationship label in ER diagrams is optional. You can define relationships without specifying a label, and the diagram will render correctly.
+
+For example, the following is valid:
+
+```mermaid-example
+erDiagram
+    BOOK }|..|{ AUTHOR
+    BOOK }|..|{ GENRE
+    AUTHOR }|..|{ GENRE
+```
+
+This will show the relationships between the entities without any labels on the connecting lines.
+
+You can still add a label if you want to describe the relationship:
+
+```mermaid-example
+erDiagram
+    BOOK }|..|{ AUTHOR : written_by
+    BOOK }|..|{ GENRE : categorized_as
+    AUTHOR }|..|{ GENRE : specializes_in
+```
+
 ### Relationship Syntax
 
 The `relationship` part of each statement can be broken down into three sub-components: