Disallow comments in Genesis JSON file. (#49)

* Disallow comments in Genesis JSON file

Signed-off-by: Abdelhamid Bakhta <abdelhamid.bakhta@consensys.net>

config/src/main/java/org/hyperledger/besu/config/GenesisConfigFile.java

@@ -23,7 +23,6 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.stream.Stream;
 
-import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.collect.Streams;
 import com.google.common.io.Resources;
@@ -72,23 +71,7 @@ public class GenesisConfigFile {
   }
 
   public static GenesisConfigFile fromConfig(final String jsonString) {
-    try {
-      final ObjectNode rootNode = JsonUtil.objectNodeFromString(jsonString, false);
-      return fromConfig(rootNode);
-    } catch (final RuntimeException re) {
-      if (re.getCause() instanceof JsonParseException) {
-        // we had a runtime exception cause by a jsom parse exception.
-        // try again with comments enabled
-        final ObjectNode rootNode = JsonUtil.objectNodeFromString(jsonString, true);
-        // if we get here comments is what broke things, warn and move on.
-        LOG.warn(
-            "The provided genesis file contains comments. "
-                + "In a future release of Besu this will not be supported.");
-        return fromConfig(rootNode);
-      } else {
-        throw re;
-      }
-    }
+    return fromConfig(JsonUtil.objectNodeFromString(jsonString, false));
   }
 
   public static GenesisConfigFile fromConfig(final ObjectNode config) {

config/src/test/java/org/hyperledger/besu/config/GenesisConfigFileTest.java

@@ -24,6 +24,7 @@ import java.util.TreeMap;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import com.fasterxml.jackson.core.JsonParseException;
 import org.assertj.core.api.ThrowableAssert.ThrowingCallable;
 import org.junit.Test;
 
@@ -208,14 +209,13 @@ public class GenesisConfigFileTest {
   }
 
   @Test
-  public void acceptComments() {
-    // this test will change in the future to reject comments.
-    final GenesisConfigFile config =
-        GenesisConfigFile.fromConfig(
-            "{\"config\": { \"chainId\": 2017 }\n/* C comment }*/\n//C++ comment }\n}");
-
-    assertThat(config.getConfigOptions().getChainId()).contains(new BigInteger("2017"));
-    // Unfortunately there is no good (non-flakey) way to assert logs.
+  public void mustNotAcceptComments() {
+    assertThatThrownBy(
+            () ->
+                GenesisConfigFile.fromConfig(
+                    "{\"config\": { \"chainId\": 2017 }\n/* C comment }*/\n//C++ comment }\n}"))
+        .hasCauseInstanceOf(JsonParseException.class)
+        .hasMessageContaining("Unexpected character ('/'");
   }
 
   @Test