Passing tests

packages/parser/src/language/treemap/treemap-validator.ts

@@ -0,0 +1,77 @@
+import type { ValidationAcceptor, ValidationChecks } from 'langium';
+import type { MermaidAstType, TreemapDoc, TreemapRow } from '../generated/ast.js';
+import type { TreemapServices } from './module.js';
+
+/**
+ * Register custom validation checks.
+ */
+export function registerValidationChecks(services: TreemapServices) {
+  const validator = services.validation.TreemapValidator;
+  const registry = services.validation.ValidationRegistry;
+  if (registry) {
+    // Use any to bypass type checking since we know TreemapDoc is part of the AST
+    // but the type system is having trouble with it
+    const checks: ValidationChecks<MermaidAstType> = {
+      TreemapDoc: validator.checkSingleRoot.bind(validator),
+      TreemapRow: (node: TreemapRow, accept: ValidationAcceptor) => {
+        validator.checkSingleRootRow(node, accept);
+      },
+    };
+    registry.register(checks, validator);
+  }
+}
+
+/**
+ * Implementation of custom validations.
+ */
+export class TreemapValidator {
+  constructor() {
+    // eslint-disable-next-line no-console
+    console.debug('TreemapValidator constructor');
+  }
+  checkSingleRootRow(_node: TreemapRow, _accept: ValidationAcceptor): void {
+    // eslint-disable-next-line no-console
+    console.debug('CHECKING SINGLE ROOT Row');
+  }
+
+  /**
+   * Validates that a treemap has only one root node.
+   * A root node is defined as a node that has no indentation.
+   */
+  checkSingleRoot(doc: TreemapDoc, accept: ValidationAcceptor): void {
+    // eslint-disable-next-line no-console
+    console.debug('CHECKING SINGLE ROOT');
+    let rootNodeIndentation;
+
+    for (const row of doc.TreemapRows) {
+      // Skip non-node items (e.g., class decorations, icon decorations)
+      if (
+        !row.item ||
+        row.item.$type === 'ClassDecoration' ||
+        row.item.$type === 'IconDecoration'
+      ) {
+        continue;
+      }
+      if (
+        rootNodeIndentation === undefined && // Check if this is a root node (no indentation)
+        row.indent === undefined
+      ) {
+        rootNodeIndentation = 0;
+      } else if (row.indent === undefined) {
+        // If we've already found a root node, report an error
+        accept('error', 'Multiple root nodes are not allowed in a treemap.', {
+          node: row,
+          property: 'item',
+        });
+      } else if (
+        rootNodeIndentation !== undefined &&
+        rootNodeIndentation >= parseInt(row.indent, 10)
+      ) {
+        accept('error', 'Multiple root nodes are not allowed in a treemap.', {
+          node: row,
+          property: 'item',
+        });
+      }
+    }
+  }
+}