fix: support numeric/boolean properties and limit nesting depth

Author: vikksr

packages/cli/src/linter/model/handler.test.ts

@@ -631,4 +631,38 @@ describe('ModelHandler', () => {
       expect(card?.properties.get('disabled') as unknown).toBe(false);
     });
   });
+
+  describe('token nesting depth limit', () => {
+    it('emits error when token nesting depth exceeds 20', () => {
+      // 22 levels: Level 1..21 are objects, Level 22 is a leaf.
+      // forEachLeaf will be called for Level 22 with depth 21.
+      let obj: any = '#ffffff';
+      for (let i = 22; i >= 1; i--) {
+        obj = { [`level${i}`]: obj };
+      }
+
+      const result = handler.execute(makeParsed({
+        colors: obj,
+      }));
+      expect(result.findings.some((f) => f.message.includes('nesting depth'))).toBe(true);
+      expect(result.findings.find((f) => f.message.includes('nesting depth'))?.path).toBe('colors');
+    });
+
+    it('allows nesting up to depth 20', () => {
+      // 21 levels: Level 1..20 are objects, Level 21 is a leaf.
+      // forEachLeaf will be called for Level 21 with depth 20.
+      let obj: any = '#ffffff';
+      for (let i = 21; i >= 1; i--) {
+        obj = { [`level${i}`]: obj };
+      }
+
+      const result = handler.execute(makeParsed({
+        colors: obj,
+      }));
+      expect(result.findings.some((f) => f.message.includes('nesting depth'))).toBe(false);
+      // Construct the expected path: level1.level2...level21
+      const path = Array.from({ length: 21 }, (_, i) => `level${i + 1}`).join('.');
+      expect(result.designSystem.colors.has(path)).toBe(true);
+    });
+  });
 });

packages/cli/src/linter/model/handler.ts

@@ -29,6 +29,7 @@ import { isValidColor, isParseableDimension, isTokenReference, parseDimensionPar
 import { parseCssColor } from './color-parser.js';
 
 const MAX_REFERENCE_DEPTH = 10;
+const MAX_TOKEN_NESTING_DEPTH = 20;
 
 const SCHEMA_KEY_SET: ReadonlySet<string> = new Set(SCHEMA_KEYS);
 
@@ -68,7 +69,7 @@ export class ModelHandler implements ModelSpec {
             // Store as-is for fallback
             symbolTable.set(`colors.${name}`, raw);
           }
-        });
+        }, '', 0, findings, 'colors');
       }
 
       // Typography
@@ -106,7 +107,7 @@ export class ModelHandler implements ModelSpec {
               symbolTable.set(`rounded.${name}`, raw);
             }
           }
-        });
+        }, '', 0, findings, 'rounded');
       }
 
       // Spacing
@@ -119,7 +120,7 @@ export class ModelHandler implements ModelSpec {
           } else {
             symbolTable.set(`spacing.${name}`, raw);
           }
-        });
+        }, '', 0, findings, 'spacing');
       }
 
       // ── Phase 2: Resolve chained color references ──────────────────
@@ -396,11 +397,31 @@ export function contrastRatio(a: ResolvedColor, b: ResolvedColor): number {
  * Recursively iterate over an object and call a function for each leaf node.
  * Leaf node paths are dot-separated (e.g. "background.light").
  */
-function forEachLeaf(obj: Record<string, any>, fn: (path: string, value: any) => void, prefix = '') {
+function forEachLeaf(
+  obj: Record<string, any>,
+  fn: (path: string, value: any) => void,
+  prefix = '',
+  depth = 0,
+  findings?: Finding[],
+  rootPath?: string
+) {
+  if (depth > MAX_TOKEN_NESTING_DEPTH) {
+    if (findings && rootPath) {
+      // Check if we've already reported this rootPath to avoid spamming
+      if (!findings.some((f) => f.path === rootPath && f.message.includes('nesting depth'))) {
+        findings.push({
+          severity: 'error',
+          path: rootPath,
+          message: `Token nesting depth exceeds maximum allowed depth of ${MAX_TOKEN_NESTING_DEPTH}.`,
+        });
+      }
+    }
+    return;
+  }
   for (const [key, value] of Object.entries(obj)) {
     const fullPath = prefix ? `${prefix}.${key}` : key;
     if (value !== null && typeof value === 'object' && !Array.isArray(value)) {
-      forEachLeaf(value, fn, fullPath);
+      forEachLeaf(value, fn, fullPath, depth + 1, findings, rootPath);
     } else {
       fn(fullPath, value);
     }

packages/cli/src/linter/model/spec.ts

@@ -61,7 +61,7 @@ export interface ResolvedTypography {
   fontVariation?: string | undefined;
 }
 
-export type ResolvedValue = ResolvedColor | ResolvedDimension | ResolvedTypography | string;
+export type ResolvedValue = ResolvedColor | ResolvedDimension | ResolvedTypography | string | number | boolean;
 
 // ── Re-exported from spec-config (single source of truth) ─────────
 export const VALID_TYPOGRAPHY_PROPS = _VALID_TYPOGRAPHY_PROPS;
@@ -98,6 +98,7 @@ export const ModelErrorCode = z.enum([
   'UNRESOLVED_REFERENCE',
   'CIRCULAR_REFERENCE',
   'REFERENCE_TO_NON_PRIMITIVE',
+  'NESTING_DEPTH_EXCEEDED',
   'UNKNOWN_ERROR',
 ]);