From 1be82f02e2c6967ff90ec154d2f6434d0e96e7cb Mon Sep 17 00:00:00 2001
From: SamyaDaleh <samya.daleh@freenet.de>
Date: Tue, 12 Dec 2023 13:00:50 +0100
Subject: [PATCH] #301 fix tree generation

---
 .../cltoolbox/chartparsing/Deduction.java     | 31 +++++++++++++------
 .../cfg/shiftreduce/CfgBottomUpReduce.java    | 18 +++++++++--
 2 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/Deduction.java b/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/Deduction.java
index 5a05ec1..3c52a67 100644
--- a/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/Deduction.java
+++ b/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/Deduction.java
@@ -546,21 +546,32 @@ private static void mergeTrees(BottomUpChartItem oldItem,
       Map<Integer, List<Tree>> oldTreeMap = oldStackState.get(i).getSecond();
       Map<Integer, List<Tree>> newTreeMap = newStackState.get(i).getSecond();
 
-      for (Map.Entry<Integer, List<Tree>> newTreeEntry : newTreeMap.entrySet()) {
-        oldTreeMap.merge(newTreeEntry.getKey(), newTreeEntry.getValue(),
-            (oldTrees, newTrees) -> {
-              for (Tree newTree : newTrees) {
-                if (!oldTrees.contains(newTree)) {
-                  oldTrees.add(newTree);
-                }
-              }
-              return oldTrees;
-            });
+      combineMaps(oldTreeMap, newTreeMap);
+    }
+  }
+
+  private static void combineMaps(
+      Map<Integer, List<Tree>> oldTreeMap,
+      Map<Integer, List<Tree>> newTreeMap) {
+    for (Map.Entry<Integer, List<Tree>> newTreeEntry
+        : newTreeMap.entrySet()) {
+      Integer key = newTreeEntry.getKey();
+      List<Tree> newTrees = newTreeEntry.getValue();
+      if (oldTreeMap.containsKey(key)) {
+        List<Tree> oldTrees = oldTreeMap.get(key);
+        for (Tree newTree : newTrees) {
+          if (!oldTrees.contains(newTree)) {
+            oldTrees.add(newTree);
+          }
+        }
+      } else {
+        oldTreeMap.put(key, newTrees);
       }
     }
   }
 
 
+
   /**
    * Pretty-prints rows of the parsing process by filling up all columns up to a
    * specific length with spaces..
diff --git a/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/cfg/shiftreduce/CfgBottomUpReduce.java b/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/cfg/shiftreduce/CfgBottomUpReduce.java
index ae66548..098f6cc 100644
--- a/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/cfg/shiftreduce/CfgBottomUpReduce.java
+++ b/src/main/java/com/github/samyadaleh/cltoolbox/chartparsing/cfg/shiftreduce/CfgBottomUpReduce.java
@@ -42,7 +42,8 @@ public CfgBottomUpReduce(CfgProductionRule rule) {
     }
     BottomUpChartItem consequence = createConsequence(i, gamma);
     List<Pair<String, Map<Integer, List<Tree>>>> derivedTrees =
-        new ArrayList<>(((BottomUpChartItem) antecedences.get(0)).getStackState());
+        duplicateStackState((
+            (BottomUpChartItem) antecedences.get(0)).getStackState());
     try {
       Tree derivedTreeBase = new Tree(rule);
       if (derivedTrees.size() == 0) {
@@ -80,6 +81,19 @@ public CfgBottomUpReduce(CfgProductionRule rule) {
     return consequences;
   }
 
+  private List<Pair<String, Map<Integer, List<Tree>>>> duplicateStackState(
+      List<Pair<String, Map<Integer, List<Tree>>>> stackState) {
+    List<Pair<String, Map<Integer, List<Tree>>>> duplicateStackState =
+        new ArrayList<>();
+    for (Pair<String, Map<Integer, List<Tree>>> pair : stackState) {
+      Map<Integer, List<Tree>> mapCopy = pair.getSecond();
+      Pair<String, Map<Integer, List<Tree>>> dupPair =
+          new Pair<>(pair.getFirst(), mapCopy);
+      duplicateStackState.add(dupPair);
+    }
+    return duplicateStackState;
+  }
+
   private void handleDerivedTreeBaseList(
       List<Pair<String, Map<Integer, List<Tree>>>> derivedTrees,
       Tree derivedTreeBase) {
@@ -97,7 +111,7 @@ private RhsTreesListAndRequiredLength getRhsTreesListAndRequiredLength(
     List<Pair<String, Map<Integer, List<Tree>>>> rhsTreesLists = new ArrayList<>();
     List<String> rhsSymbols = Arrays.asList(rule.getRhs());
 
-    int rhsIndex = rhsSymbols.size()-1;
+    int rhsIndex = rhsSymbols.size() - 1;
     int terminalsBetween = 0;
     int requiredLength = 0;
     for (Pair<String, Map<Integer, List<Tree>>> treePair : derivedTrees) {