More test cases for DTD validation (#115)

jameslan · web-flow · commit 0c52afbbbd2f · 2025-08-06T23:05:34.000-07:00
diff --git a/src/document.mts b/src/document.mts
@@ -132,15 +132,22 @@ function parse<Input>(
         xmlOptions,
     );
     try {
-        if (!xml) {
-            const errDetails = error.storage.get(errIndex);
+        const errDetails = error.storage.get(errIndex);
+        if (errDetails.length > 0) {
+            if (!xml) {
+                xmlFreeDoc(xml);
+            }
             throw new XmlParseError(errDetails!.map((d) => d.message).join(''), errDetails!);
         }
     } finally {
         error.storage.free(errIndex);
         xmlFreeParserCtxt(ctxt);
     }
 
+    if (!xml) {
+        // no error from libxml2, but failed to parse. Usually due to invalid input.
+        throw new XmlParseError('Failed to parse XML', []);
+    }
     const xmlDocument = XmlDocument.getInstance(xml);
     if (xmlOptions & ParseOption.XML_PARSE_XINCLUDE) {
         xmlDocument.processXInclude();
diff --git a/test/crossplatform/document.spec.mts b/test/crossplatform/document.spec.mts
@@ -1,11 +1,13 @@
 import { expect } from 'chai';
 import {
+    ParseOption,
     XmlBufferInputProvider,
     xmlCleanupInputProvider,
     XmlDocument,
     XmlElement,
     XmlError,
     XmlNode,
+    XmlParseError,
     xmlRegisterInputProvider,
 } from '@libxml2-wasm/lib/index.mjs';
 import { XmlStringOutputBufferHandler } from '@libxml2-wasm/lib/utils.mjs';
@@ -201,6 +203,25 @@ describe('XmlDocument', () => {
             using xml = XmlDocument.fromString('<docs><doc/></docs>');
             expect(xml.dtd).to.be.null;
         });
+
+        it('should validate dtd', () => {
+            // missing element heading and body
+            expect(() => XmlDocument.fromString(
+                `<?xml version="1.0"?>
+<!DOCTYPE note [
+<!ELEMENT note (to,from,heading,body)>
+<!ELEMENT to (#PCDATA)>
+<!ELEMENT from (#PCDATA)>
+<!ELEMENT heading (#PCDATA)>
+<!ELEMENT body (#PCDATA)>
+]>
+<note>
+<to>Tove</to>
+<from>Jani</from>
+</note>`,
+                { option: ParseOption.XML_PARSE_DTDVALID },
+            )).to.throw(XmlParseError);
+        });
     });
 
     describe('eval', () => {
diff --git a/test/crossplatform/dtd.spec.mts b/test/crossplatform/dtd.spec.mts
@@ -1,9 +1,14 @@
 import { expect } from 'chai';
 import {
     DtdValidator,
+    ParseOption,
+    XmlBufferInputProvider,
+    xmlCleanupInputProvider,
     XmlDocument,
     XmlDtd,
     XmlParseError,
+    xmlRegisterInputProvider,
+    XmlValidateError,
 } from '@libxml2-wasm/lib/index.mjs';
 
 describe('XmlDtd', () => {
@@ -105,4 +110,57 @@ describe('XmlDtd', () => {
 <ELEMENT from (#PCDATA)>
 `)).to.throw(XmlParseError, 'Content error in the external subset');
     });
+
+    it('fails DTD validation when document does not conform', () => {
+        using dtd = XmlDtd.fromString(`
+<!ELEMENT note (to,from,heading,body)>
+<!ELEMENT to (#PCDATA)>
+<!ELEMENT from (#PCDATA)>
+<!ELEMENT heading (#PCDATA)>
+<!ELEMENT body (#PCDATA)>
+`);
+        using validator = new DtdValidator(dtd);
+
+        // XML document missing required 'heading' and 'body' elements
+        using xml = XmlDocument.fromString(`\
+<?xml version="1.0"?>
+<note>
+<to>Tove</to>
+<from>Jani</from>
+</note>`);
+
+        expect(() => validator.validate(xml)).to.throw(XmlValidateError);
+    });
+
+    describe('load external subset', () => {
+        afterEach(() => {
+            xmlCleanupInputProvider();
+        });
+
+        it('validate with external subset', () => {
+            const buffers = new XmlBufferInputProvider({
+                'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd': new TextEncoder().encode(`\
+<!ELEMENT note (to,from,heading,body)>
+<!ELEMENT to (#PCDATA)>
+<!ELEMENT from (#PCDATA)>
+<!ELEMENT heading (#PCDATA)>
+<!ELEMENT body (#PCDATA)>
+`),
+            });
+            xmlRegisterInputProvider(buffers);
+
+            // missing element heading and body
+            using xml = XmlDocument.fromString(`\
+<?xml version="1.0"?>
+<!DOCTYPE html PUBLIC
+  "-//W3C//DTD XHTML 1.0 Transitional//EN"
+  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<note>
+<to>Tove</to>
+<from>Jani</from>
+</note>`, { option: ParseOption.XML_PARSE_DTDLOAD }); // this option is required to load external subset
+            using validator = new DtdValidator(xml.dtd!);
+            expect(() => validator.validate(xml)).to.throw(XmlValidateError);
+        });
+    });
 });
