Fix #93: handle split surrogate for PI writes too (#94)

Author: cowtowncoder

release-notes/VERSION

@@ -12,6 +12,8 @@ Project: aalto-xml
 #90: Update stax2-api dep to 4.2.2 (from 4.2)
 #91: Multi-byte characters are split in `writeComment()` if first byte sits
   right at the end of the buffer
+#93: Multi-byte characters are split in `writePI()` if first byte sits
+  right at the end of the buffer
 
 1.3.2 (25-Apr-2022)
 

src/main/java/com/fasterxml/aalto/out/ByteXmlWriter.java

@@ -1193,7 +1193,7 @@ public int writeComment(String data) throws IOException, XMLStreamException
 
     /**
      * Note: the only way to fix comment contents is to inject a space
-     * to split up consequtive '--' (or '-' that ends a comment).
+     * to split up consecutive '--' (or '-' that ends a comment).
      */
     protected int writeCommentContents(char[] cbuf, int offset, int len)
         throws IOException, XMLStreamException
@@ -1293,6 +1293,14 @@ public void writeDTD(WName rootName, String systemId, String publicId,
     protected int writePIData(char[] cbuf, int offset, int len)
         throws IOException, XMLStreamException
     {
+        if (_surrogate != 0) {
+            outputSurrogates(_surrogate, cbuf[offset]);
+            // reset the temporary surrogate storage
+            _surrogate = 0;
+            ++offset;
+            --len;
+        }
+
         // Unlike with writeCharacters() and fastWriteName(), let's not
         // worry about split buffers here: this is unlikely to become
         // performance bottleneck. This allows keeping it simple; and

src/test/java/com/fasterxml/aalto/sax/TestSaxWriter.java

@@ -7,6 +7,19 @@
 
 public class TestSaxWriter extends base.BaseTestCase
 {
+    private final String TEXT_WITH_SURROGATE;
+    {
+        StringBuilder testText = new StringBuilder(1025);
+        for (int i = 0; i < 511; i++) {
+            testText.append('x');
+        }
+        testText.append("\uD835\uDFCE");
+        for (int i = 0; i < 512; i++) {
+            testText.append('x');
+        }
+        TEXT_WITH_SURROGATE = testText.toString();
+    }
+
     public void testSplitSurrogateWithAttributeValue() throws Exception
     {
         // This test aims to produce the
@@ -16,19 +29,11 @@ public void testSplitSurrogateWithAttributeValue() throws Exception
         // to also fill the next two internal reading buffers. Then, the code would try to fuse the first byte
         // of the original multi-byte character with the first character in the third buffer because
         // ByteXmlWriter#_surrogate was not set back to 0 after writing the original multi-byte character.
-        StringBuilder testText = new StringBuilder();
-        for (int i = 0; i < 511; i++) {
-            testText.append('x');
-        }
-        testText.append("\uD835\uDFCE");
-        for (int i = 0; i < 512; i++) {
-            testText.append('x');
-        }
         WriterConfig writerConfig = new WriterConfig();
         ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
         Utf8XmlWriter writer = new Utf8XmlWriter(writerConfig, byteArrayOutputStream);
         writer.writeStartTagStart(writer.constructName("testelement"));
-        writer.writeAttribute(writer.constructName("testattr"), testText.toString());
+        writer.writeAttribute(writer.constructName("testattr"), TEXT_WITH_SURROGATE);
         writer.writeStartTagEnd();
         writer.writeEndTag(writer.constructName("testelement"));
         writer.close(false);
@@ -61,43 +66,37 @@ public void testSplitSurrogateWithAttributeValue2() throws Exception
     public void testSplitSurrogateWithCData() throws Exception
     {
         // Modification of "testSplitSurrogateWithAttributeValue()" but for CDATA
-        StringBuilder testText = new StringBuilder();
-        for (int i = 0; i < 511; i++) {
-            testText.append('x');
-        }
-        testText.append("\uD835\uDFCE");
-        for (int i = 0; i < 512; i++) {
-            testText.append('x');
-        }
-
         WriterConfig writerConfig = new WriterConfig();
         ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
         Utf8XmlWriter writer = new Utf8XmlWriter(writerConfig, byteArrayOutputStream);
         writer.writeStartTagStart(writer.constructName("testelement"));
-        writer.writeCData(testText.toString());
+        writer.writeCData(TEXT_WITH_SURROGATE);
         writer.writeStartTagEnd();
         writer.writeEndTag(writer.constructName("testelement"));
         writer.close(false);
     }
 
-
     public void testSplitSurrogateWithComment() throws Exception
     {
         // Modification of "testSplitSurrogateWithAttributeValue()" but for Comment
-        StringBuilder testText = new StringBuilder();
-        for (int i = 0; i < 511; i++) {
-            testText.append('x');
-        }
-        testText.append("\uD835\uDFCE");
-        for (int i = 0; i < 512; i++) {
-            testText.append('x');
-        }
+        WriterConfig writerConfig = new WriterConfig();
+        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
+        Utf8XmlWriter writer = new Utf8XmlWriter(writerConfig, byteArrayOutputStream);
+        writer.writeStartTagStart(writer.constructName("testelement"));
+        writer.writeComment(TEXT_WITH_SURROGATE);
+        writer.writeStartTagEnd();
+        writer.writeEndTag(writer.constructName("testelement"));
+        writer.close(false);
+    }
 
+    public void testSplitSurrogateWithPI() throws Exception
+    {
+        // Modification of "testSplitSurrogateWithAttributeValue()" but for Processing instructions
         WriterConfig writerConfig = new WriterConfig();
         ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
         Utf8XmlWriter writer = new Utf8XmlWriter(writerConfig, byteArrayOutputStream);
         writer.writeStartTagStart(writer.constructName("testelement"));
-        writer.writeComment(testText.toString());
+        writer.writePI(writer.constructName("target"), TEXT_WITH_SURROGATE);
         writer.writeStartTagEnd();
         writer.writeEndTag(writer.constructName("testelement"));
         writer.close(false);