From 274053ce7aad940af455f430a5e59fd8ced07454 Mon Sep 17 00:00:00 2001
From: Justin Greywolf <jgreywolf@users.noreply.github.com>
Date: Sat, 11 Oct 2025 14:33:47 -0700
Subject: [PATCH] fix: Support multiple stereotypes on class diagrams (#6680)

- Modified JISON grammar to support consecutive annotations like <<interface>><<injected>>
- Updated addAnnotation method to create classes if they don't exist
- Added comprehensive tests for multiple annotation scenarios
- Maintains backward compatibility with existing single annotation syntax

Fixes #6680
---
 .../mermaid/src/diagrams/class/classDb.ts     |  1 +
 .../src/diagrams/class/classDiagram.spec.ts   | 22 +++++++++++++++++++
 .../diagrams/class/parser/classDiagram.jison  |  7 +++++-
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/packages/mermaid/src/diagrams/class/classDb.ts b/packages/mermaid/src/diagrams/class/classDb.ts
index e3d4e0bcf..5deb383f7 100644
--- a/packages/mermaid/src/diagrams/class/classDb.ts
+++ b/packages/mermaid/src/diagrams/class/classDb.ts
@@ -237,6 +237,7 @@ export class ClassDB implements DiagramDB {
    * @public
    */
   public addAnnotation(className: string, annotation: string) {
+    this.addClass(className);
     const validatedClassName = this.splitClassNameAndType(className).className;
     this.classes.get(validatedClassName)!.annotations.push(annotation);
   }
diff --git a/packages/mermaid/src/diagrams/class/classDiagram.spec.ts b/packages/mermaid/src/diagrams/class/classDiagram.spec.ts
index aa5e514e0..544a25a46 100644
--- a/packages/mermaid/src/diagrams/class/classDiagram.spec.ts
+++ b/packages/mermaid/src/diagrams/class/classDiagram.spec.ts
@@ -922,6 +922,28 @@ foo()
       expect(actual.methods.length).toBe(1);
       expect(actual.annotations[0]).toBe('interface');
     });
+
+    it('should handle multiple consecutive annotations on a single class', function () {
+      const str = 'classDiagram\n' + '<<interface>><<injected>> Class1';
+
+      parser.parse(str);
+
+      const actual = parser.yy.getClass('Class1');
+      expect(actual.annotations.length).toBe(2);
+      expect(actual.annotations).toContain('interface');
+      expect(actual.annotations).toContain('injected');
+    });
+
+    it('should handle multiple separate annotations on a single class', function () {
+      const str = 'classDiagram\n' + '<<interface>> Class1\n' + '<<injected>> Class1';
+
+      parser.parse(str);
+
+      const actual = parser.yy.getClass('Class1');
+      expect(actual.annotations.length).toBe(2);
+      expect(actual.annotations).toContain('interface');
+      expect(actual.annotations).toContain('injected');
+    });
   });
 });
 
diff --git a/packages/mermaid/src/diagrams/class/parser/classDiagram.jison b/packages/mermaid/src/diagrams/class/parser/classDiagram.jison
index 9a1f991a7..ad3670582 100644
--- a/packages/mermaid/src/diagrams/class/parser/classDiagram.jison
+++ b/packages/mermaid/src/diagrams/class/parser/classDiagram.jison
@@ -310,7 +310,12 @@ emptyBody
     ;
 
 annotationStatement
-    : ANNOTATION_START alphaNumToken ANNOTATION_END className  { yy.addAnnotation($4,$2); }
+    : annotationList className  { for(const annotation of $1) { yy.addAnnotation($2, annotation); } }
+    ;
+
+annotationList
+    : ANNOTATION_START alphaNumToken ANNOTATION_END { $$ = [$2]; }
+    | annotationList ANNOTATION_START alphaNumToken ANNOTATION_END { $1.push($3); $$ = $1; }
     ;
 
 members