Fix #1015: JsonFactory always respects CANONICALIZE_FIELD_NAMES (#1016

)

Previously a subset of methods did not check for
`CANONICALIZE_FIELD_NAMES` in the factory features configuration.

src/main/java/com/fasterxml/jackson/core/JsonFactory.java

@@ -1299,7 +1299,7 @@ public JsonParser createNonBlockingByteArrayParser() throws IOException
         //   for non-JSON input:
         _requireJSONFactory("Non-blocking source not (yet?) supported for this format (%s)");
         IOContext ctxt = _createNonBlockingContext(null);
-        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChild(_factoryFeatures);
+        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChildOrPlaceholder(_factoryFeatures);
         return new NonBlockingJsonParser(ctxt, _parserFeatures, can);
     }
 
@@ -1326,7 +1326,7 @@ public JsonParser createNonBlockingByteBufferParser() throws IOException
         //   for non-JSON input:
         _requireJSONFactory("Non-blocking source not (yet?) supported for this format (%s)");
         IOContext ctxt = _createNonBlockingContext(null);
-        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChild(_factoryFeatures);
+        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChildOrPlaceholder(_factoryFeatures);
         return new NonBlockingByteBufferJsonParser(ctxt, _parserFeatures, can);
     }
 
@@ -1849,7 +1849,7 @@ protected JsonParser _createParser(DataInput input, IOContext ctxt) throws IOExc
         // Also: while we can't do full bootstrapping (due to read-ahead limitations), should
         // at least handle possible UTF-8 BOM
         int firstByte = ByteSourceJsonBootstrapper.skipUTF8BOM(input);
-        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChild(_factoryFeatures);
+        ByteQuadsCanonicalizer can = _byteSymbolCanonicalizer.makeChildOrPlaceholder(_factoryFeatures);
         return new UTF8DataInputJsonParser(ctxt, _parserFeatures, input,
                 _objectCodec, can, firstByte);
     }

src/main/java/com/fasterxml/jackson/core/json/UTF8DataInputJsonParser.java

@@ -1933,6 +1933,10 @@ private final String addName(int[] quads, int qlen, int lastQuadBytes)
 
         // Ok. Now we have the character array, and can construct the String
         String baseName = new String(cbuf, 0, cix);
+        // 5-May-2023, ckozak: [core#1015] respect CANONICALIZE_FIELD_NAMES factory config.
+        if (!_symbols.isCanonicalizing()) {
+            return baseName;
+        }
         // And finally, un-align if necessary
         if (lastQuadBytes < 4) {
             quads[qlen-1] = lastQuad;

src/main/java/com/fasterxml/jackson/core/json/async/NonBlockingJsonParserBase.java

@@ -790,6 +790,10 @@ protected final String _addName(int[] quads, int qlen, int lastQuadBytes)
 
         // Ok. Now we have the character array, and can construct the String
         String baseName = new String(cbuf, 0, cix);
+        // 5-May-2023, ckozak: [core#1015] respect CANONICALIZE_FIELD_NAMES factory config.
+        if (!_symbols.isCanonicalizing()) {
+            return baseName;
+        }
         // And finally, un-align if necessary
         if (lastQuadBytes < 4) {
             quads[qlen-1] = lastQuad;

src/test/java/com/fasterxml/jackson/core/json/JsonFactoryTest.java

@@ -1,9 +1,11 @@
 package com.fasterxml.jackson.core.json;
 
 import java.io.*;
+import java.nio.charset.StandardCharsets;
 import java.util.Iterator;
 
 import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.core.json.async.NonBlockingJsonParser;
 import com.fasterxml.jackson.core.type.ResolvedType;
 import com.fasterxml.jackson.core.type.TypeReference;
 
@@ -288,4 +290,65 @@ public void testRootValues() throws Exception
         g.close();
         assertEquals("1/2/3", w.toString());
     }
+
+    public void testCanonicalizationEnabled() throws Exception {
+        doCanonicalizationTest(false);
+    }
+
+    public void testCanonicalizationDisabled() throws Exception {
+        doCanonicalizationTest(false);
+    }
+
+    // Configure the JsonFactory as expected, and verify across common shapes of input
+    // to cover common JsonParser implementations.
+    private void doCanonicalizationTest(boolean canonicalize) throws Exception {
+        String contents = "{\"a\":true,\"a\":true}";
+        JsonFactory factory = JsonFactory.builder()
+                .configure(JsonFactory.Feature.CANONICALIZE_FIELD_NAMES, canonicalize)
+                .build();
+        try (JsonParser parser = factory.createParser(contents)) {
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+        try (JsonParser parser = factory.createParser(contents.getBytes(StandardCharsets.UTF_8))) {
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+        try (JsonParser parser = factory.createParser(
+                new ByteArrayInputStream(contents.getBytes(StandardCharsets.UTF_8)))) {
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+        try (JsonParser parser = factory.createParser(new StringReader(contents))) {
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+        try (JsonParser parser = factory.createParser((DataInput) new DataInputStream(
+                new ByteArrayInputStream(contents.getBytes(StandardCharsets.UTF_8))))) {
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+        try (NonBlockingJsonParser parser = (NonBlockingJsonParser) factory.createNonBlockingByteArrayParser()) {
+            byte[] data = contents.getBytes(StandardCharsets.UTF_8);
+            parser.feedInput(data, 0, data.length);
+            parser.endOfInput();
+            verifyCanonicalizationTestResult(parser, canonicalize);
+        }
+    }
+
+    private void verifyCanonicalizationTestResult(JsonParser parser, boolean canonicalize) throws Exception {
+        assertToken(JsonToken.START_OBJECT, parser.nextToken());
+        String field1 = parser.nextFieldName();
+        assertEquals("a", field1);
+        assertToken(JsonToken.VALUE_TRUE, parser.nextToken());
+        String field2 = parser.nextFieldName();
+        assertEquals("a", field2);
+        if (canonicalize) {
+            assertSame(field1, field2);
+        } else {
+            // n.b. It's possible that this may flake if a garbage collector with string deduplication
+            // enabled is used. Such a failure is unlikely because younger GC generations are typically
+            // not considered for deduplication due to high churn, but under heavy memory pressure it
+            // may be possible. I've left this comment in an attempt to simplify investigation in the
+            // off-chance that such flakes eventually occur.
+            assertNotSame(field1, field2);
+        }
+        assertToken(JsonToken.VALUE_TRUE, parser.nextToken());
+        assertToken(JsonToken.END_OBJECT, parser.nextToken());
+    }
 }