Merge pull request #124 from lppedd/refactor/runtime

Port additional runtime fixes and apply minor cleanups

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/DefaultErrorStrategy.kt

@@ -133,10 +133,12 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    * that can follow the current rule.
    */
   override fun recover(recognizer: Parser, e: RecognitionException) {
+    var lastErrorStatesTemp = lastErrorStates
+
     if (
       lastErrorIndex == recognizer.tokenStream.index() &&
-      lastErrorStates != null &&
-      lastErrorStates!!.contains(recognizer.state)
+      lastErrorStatesTemp != null &&
+      lastErrorStatesTemp.contains(recognizer.state)
     ) {
       // Uh oh, another error at same token index and previously-visited
       // state in ATN; must be a case where LT(1) is in the recovery
@@ -147,11 +149,12 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
 
     lastErrorIndex = recognizer.tokenStream.index()
 
-    if (lastErrorStates == null) {
-      lastErrorStates = IntervalSet()
+    if (lastErrorStatesTemp == null) {
+      lastErrorStatesTemp = IntervalSet()
+      lastErrorStates = lastErrorStatesTemp
     }
 
-    lastErrorStates!!.add(recognizer.state)
+    lastErrorStatesTemp.add(recognizer.state)
 
     val followSet = getErrorRecoverySet(recognizer)
     consumeUntil(recognizer, followSet)
@@ -269,7 +272,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    *
    * @see reportError
    */
-  protected fun reportNoViableAlternative(recognizer: Parser, e: NoViableAltException) {
+  protected open fun reportNoViableAlternative(recognizer: Parser, e: NoViableAltException) {
     val tokens = recognizer.tokenStream
     val input = if (e.startToken!!.type == Token.EOF) {
       "<EOF>"
@@ -289,7 +292,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    *
    * @see reportError
    */
-  protected fun reportInputMismatch(recognizer: Parser, e: InputMismatchException) {
+  protected open fun reportInputMismatch(recognizer: Parser, e: InputMismatchException) {
     val tokenErrorDisplay = getTokenErrorDisplay(e.offendingToken)
     val expectedToken = e.expectedTokens!!.toString(recognizer.vocabulary)
     val msg = "mismatched input $tokenErrorDisplay expecting $expectedToken"
@@ -304,7 +307,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    *
    * @see reportError
    */
-  protected fun reportFailedPredicate(recognizer: Parser, e: FailedPredicateException) {
+  protected open fun reportFailedPredicate(recognizer: Parser, e: FailedPredicateException) {
     val ruleName = recognizer.ruleNames[recognizer.context!!.ruleIndex]
     val msg = "rule $ruleName ${e.message}"
     recognizer.notifyErrorListeners(e.offendingToken!!, msg, e)
@@ -327,7 +330,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    *
    * @param recognizer The parser instance
    */
-  protected fun reportUnwantedToken(recognizer: Parser) {
+  protected open fun reportUnwantedToken(recognizer: Parser) {
     if (inErrorRecoveryMode(recognizer)) {
       return
     }
@@ -357,7 +360,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    *
    * @param recognizer The parser instance
    */
-  protected fun reportMissingToken(recognizer: Parser) {
+  protected open fun reportMissingToken(recognizer: Parser) {
     if (inErrorRecoveryMode(recognizer)) {
       return
     }
@@ -462,8 +465,9 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    * @return `true` if single-token insertion is a viable recovery
    *   strategy for the current mismatched input, otherwise `false`
    */
-  protected fun singleTokenInsertion(recognizer: Parser): Boolean {
+  protected open fun singleTokenInsertion(recognizer: Parser): Boolean {
     val currentSymbolType = recognizer.tokenStream.LA(1)
+
     // If current token is consistent with what could come after current
     // ATN state, then we know we're missing a token; error recovery
     // is free to conjure up and insert the missing token
@@ -499,14 +503,14 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
    * @return The successfully matched [Token] instance if single-token
    *   deletion successfully recovers from the mismatched input, otherwise `null`
    */
-  protected fun singleTokenDeletion(recognizer: Parser): Token? {
+  protected open fun singleTokenDeletion(recognizer: Parser): Token? {
     val nextTokenType = recognizer.tokenStream.LA(2)
     val expecting = getExpectedTokens(recognizer)
 
     if (expecting.contains(nextTokenType)) {
       reportUnwantedToken(recognizer)
 
-      // simply delete extra token
+      // Simply delete extra token
       recognizer.consume()
 
       // We want to return the token we're actually matching
@@ -564,7 +568,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
     }
 
     return recognizer.tokenFactory.create(
-      Pair(current.tokenSource, current.tokenSource!!.inputStream),
+      Pair(current.tokenSource, current.inputStream),
       expectedTokenType,
       tokenText,
       Token.DEFAULT_CHANNEL,
@@ -596,7 +600,7 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
       return "<no token>"
     }
 
-    var s: String? = getSymbolText(t)
+    var s = getSymbolText(t)
 
     if (s == null) {
       s = if (getSymbolType(t) == Token.EOF) {
@@ -609,8 +613,8 @@ public open class DefaultErrorStrategy : ANTLRErrorStrategy {
     return escapeWSAndQuote(s)
   }
 
-  protected open fun getSymbolText(symbol: Token): String =
-    symbol.text!!
+  protected open fun getSymbolText(symbol: Token): String? =
+    symbol.text
 
   protected open fun getSymbolType(symbol: Token): Int =
     symbol.type

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/ParserInterpreter.kt

@@ -400,7 +400,7 @@ public open class ParserInterpreter(
         }
 
         val errToken = tokenFactory.create(
-          Pair(tok!!.tokenSource!!, tok.tokenSource!!.inputStream!!),
+          Pair(tok!!.tokenSource, tok.inputStream),
           expectedTokenType,
           tok.text,
           Token.DEFAULT_CHANNEL,
@@ -415,7 +415,7 @@ public open class ParserInterpreter(
         // NoViableAlt
         val tok = e.offendingToken
         val errToken = tokenFactory.create(
-          Pair(tok!!.tokenSource!!, tok.tokenSource!!.inputStream!!),
+          Pair(tok!!.tokenSource, tok.inputStream),
           Token.INVALID_TYPE,
           tok.text,
           Token.DEFAULT_CHANNEL,

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/ParserRuleContext.kt

@@ -11,7 +11,6 @@ import org.antlr.v4.kotlinruntime.tree.*
 import kotlin.jvm.JvmStatic
 import kotlin.reflect.KClass
 
-
 /**
  * A rule invocation record for parsing.
  *
@@ -160,11 +159,14 @@ public open class ParserRuleContext : RuleContext {
    * @since 4.7
    */
   public fun <T : ParseTree> addAnyChild(t: T): T {
-    if (children == null) {
-      children = ArrayList()
+    var childrenTemp = children
+
+    if (childrenTemp == null) {
+      childrenTemp = ArrayList()
+      children = childrenTemp
     }
 
-    children!!.add(t)
+    childrenTemp.add(t)
     return t
   }
 
@@ -291,44 +293,36 @@ public open class ParserRuleContext : RuleContext {
 
   public fun getTokens(ttype: Int): List<TerminalNode> {
     val tempChildren = children ?: return emptyList()
-    var tokens: MutableList<TerminalNode>? = null
+    val tokens = ArrayList<TerminalNode>()
 
     for (o in tempChildren) {
       if (o is TerminalNode) {
         val symbol = o.symbol
 
         if (symbol!!.type == ttype) {
-          if (tokens == null) {
-            tokens = ArrayList()
-          }
-
           tokens.add(o)
         }
       }
     }
 
-    return tokens ?: emptyList()
+    return tokens
   }
 
   public fun <T : ParserRuleContext> getRuleContext(ctxType: KClass<T>, i: Int): T? =
     getChild(ctxType, i)
 
   public fun <T : ParserRuleContext> getRuleContexts(ctxType: KClass<T>): List<T> {
     val tempChildren = children ?: return emptyList()
-    var contexts: MutableList<T>? = null
+    val contexts = ArrayList<T>()
 
     for (o in tempChildren) {
       if (ctxType.isInstance(o)) {
-        if (contexts == null) {
-          contexts = ArrayList()
-        }
-
         @Suppress("UNCHECKED_CAST")
         contexts.add(o as T)
       }
     }
 
-    return contexts ?: emptyList()
+    return contexts
   }
 
   /**

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/atn/DecisionInfo.kt

@@ -237,6 +237,6 @@ public class DecisionInfo(public val decision: Int) {
       append(LL_TotalLook)
       append(", LL_ATNTransitions=")
       append(LL_ATNTransitions)
-      append('}')
+      append("}")
     }
 }

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/atn/SemanticContext.kt

@@ -15,7 +15,6 @@ import org.antlr.v4.kotlinruntime.atn.SemanticContext.*
 import org.antlr.v4.kotlinruntime.misc.MurmurHash
 import kotlin.jvm.JvmStatic
 
-
 /**
  * A tree structure used to record the semantic context in which
  * an ATN configuration is valid.
@@ -70,23 +69,19 @@ public abstract class SemanticContext {
     }
 
     private fun filterPrecedencePredicates(collection: MutableCollection<out SemanticContext>): List<PrecedencePredicate> {
-      var result: ArrayList<PrecedencePredicate>? = null
+      val result = ArrayList<PrecedencePredicate>()
       val iterator = collection.iterator()
 
       while (iterator.hasNext()) {
         val context = iterator.next()
 
         if (context is PrecedencePredicate) {
-          if (result == null) {
-            result = ArrayList()
-          }
-
           result.add(context)
           iterator.remove()
         }
       }
 
-      return result ?: emptyList()
+      return result
     }
   }
 
@@ -223,7 +218,7 @@ public abstract class SemanticContext {
         return true
       }
 
-      return this.precedence == other.precedence
+      return precedence == other.precedence
     }
 
     override fun toString(): String =
@@ -258,7 +253,7 @@ public abstract class SemanticContext {
       get() = opnds.asList()
 
     init {
-      val operands = HashSet<SemanticContext>()
+      val operands = LinkedHashSet<SemanticContext>()
 
       if (a is AND) {
         operands.addAll(a.opnds.asList())
@@ -351,7 +346,7 @@ public abstract class SemanticContext {
     }
 
     override fun toString(): String =
-      opnds.asList().joinToString("&&")
+      opnds.joinToString("&&")
   }
 
   /**
@@ -365,7 +360,7 @@ public abstract class SemanticContext {
       get() = opnds.asList()
 
     init {
-      val operands = HashSet<SemanticContext>()
+      val operands = LinkedHashSet<SemanticContext>()
 
       if (a is OR) {
         operands.addAll(a.opnds.asList())
@@ -458,6 +453,6 @@ public abstract class SemanticContext {
     }
 
     override fun toString(): String =
-      opnds.asList().joinToString("||")
+      opnds.joinToString("||")
   }
 }

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/dfa/DFASerializer.kt

@@ -50,7 +50,7 @@ public open class DFASerializer(
           buf.append(getEdgeLabel(i))
           buf.append("->")
           buf.append(getStateString(t))
-          buf.append('\n')
+          buf.append("\n")
         }
       }
     }

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/misc/Array2DHashSet.kt

@@ -418,7 +418,7 @@ public open class Array2DHashSet<T>(
     }
 
     val buf = StringBuilder()
-    buf.append('{')
+    buf.append("{")
 
     var first = true
 
@@ -440,10 +440,11 @@ public open class Array2DHashSet<T>(
       }
     }
 
-    buf.append('}')
+    buf.append("}")
     return buf.toString()
   }
 
+  @Suppress("DuplicatedCode")
   public fun toTableString(): String {
     val buf = StringBuilder()
 
@@ -453,7 +454,7 @@ public open class Array2DHashSet<T>(
         continue
       }
 
-      buf.append('[')
+      buf.append("[")
       var first = true
 
       for (o in bucket) {

antlr-kotlin-runtime/src/commonMain/kotlin/org/antlr/v4/kotlinruntime/misc/FlexibleHashMap.kt

@@ -217,7 +217,7 @@ public open class FlexibleHashMap<K, V>(
 
     var first = true
     val buf = StringBuilder()
-    buf.append('{')
+    buf.append("{")
 
     for (bucket in buckets) {
       if (bucket == null) {
@@ -239,10 +239,11 @@ public open class FlexibleHashMap<K, V>(
       }
     }
 
-    buf.append('}')
+    buf.append("}")
     return buf.toString()
   }
 
+  @Suppress("DuplicatedCode")
   public fun toTableString(): String {
     val buf = StringBuilder()
 
@@ -252,7 +253,7 @@ public open class FlexibleHashMap<K, V>(
         continue
       }
 
-      buf.append('[')
+      buf.append("[")
       var first = true
 
       for (e in bucket) {