check if ranking is allowed rather than using unacceptable default

src/main/java/network/brightspots/rcv/BaseCvrReader.java

@@ -40,8 +40,8 @@ abstract void readCastVoteRecords(List<CastVoteRecord> castVoteRecords)
       throws CastVoteRecord.CvrParseException, IOException;
 
   // Individual contests may have a different value than what the config allows.
-  public Integer getMaxRankingsAllowed(String contestId) {
-    return config.getMaxRankingsAllowed();
+  public boolean isRankingAllowed(int rank, String contestId) {
+    return config.isRankingAllowed(rank);
   }
 
   // Any reader-specific validations can override this function.

src/main/java/network/brightspots/rcv/ClearBallotCvrReader.java

@@ -82,10 +82,10 @@ void readCastVoteRecords(List<CastVoteRecord> castVoteRecords)
           choiceName = Tabulator.UNDECLARED_WRITE_IN_OUTPUT_LABEL;
         }
         Integer rank = Integer.parseInt(choiceFields[RcvChoiceHeaderField.RANK.ordinal()]);
-        if (rank > this.config.getMaxRankingsAllowed()) {
+        if (!this.config.isRankingAllowed(rank)) {
           Logger.severe(
-              "Rank: %d exceeds max rankings allowed in config: %d",
-              rank, this.config.getMaxRankingsAllowed());
+              "Rank: %d exceeds max rankings allowed in config: %s",
+              rank, this.config.getMaxRankingsAllowedAsString());
           throw new CvrParseException();
         }
         columnIndexToRanking.put(columnIndex, new Pair<>(rank, choiceName));

src/main/java/network/brightspots/rcv/ContestConfig.java

@@ -678,9 +678,9 @@ private void validateRules() {
       Logger.severe("Invalid winnerElectionMode!");
     }
 
-    if (getMaxRankingsAllowed() == null
+    if (getMaxRankingsAllowedAsString() == null
         || (getNumDeclaredCandidates() >= 1
-            && getMaxRankingsAllowed() < MIN_MAX_RANKINGS_ALLOWED)) {
+            && !isRankingAllowed(MIN_MAX_RANKINGS_ALLOWED))) {
       validationErrors.add(ValidationError.RULES_MAX_RANKINGS_ALLOWED_INVALID);
       Logger.severe(
           "maxRankingsAllowed must either be \"%s\" or an integer from %d to %d!",
@@ -988,11 +988,38 @@ private String getMaxRankingsAllowedRaw() {
     return rawConfig.rules.maxRankingsAllowed;
   }
 
-  Integer getMaxRankingsAllowed() {
-    return stringToIntWithOption(
-        getMaxRankingsAllowedRaw(),
-        MAX_RANKINGS_ALLOWED_NUM_CANDIDATES_OPTION,
-        getNumDeclaredCandidates());
+  // Because the max rank can be set to "max", there's no reasonable value we can
+  // return outward. Returning MAX_VALUE could cause integer overflows if
+  // the caller tries to do arithmetic with the result (e.g. convert to a max column)
+  // Instead of returning the max rank, only allow checking via this function,
+  // or returning the value as a string for audit logging.
+  boolean isRankingAllowed(int rank) {
+    if (isMaxRankingsSetToMaximum()) {
+      return true;
+    }
+
+    return rank <= Integer.parseInt(getMaxRankingsAllowedRaw());
+  }
+
+  // There are times when it is necessary to grab the max ranking, though:
+  // notably, when writing outputs up until the max ranking, or when
+  // reading inputs where a "blank" indicates an undeclared write-in.
+  // Handle that, but ensure the caller has checked if it's set to "max"
+  Integer getMaxRankingsAllowedWhenNotSetToMaximum() {
+    if (isMaxRankingsSetToMaximum()) {
+      throw new RuntimeException(
+              "Do not call this function without first checking isMaxRankingsSetToMaximum!");
+    }
+
+    return Integer.parseInt(getMaxRankingsAllowedRaw());
+  }
+
+  boolean isMaxRankingsSetToMaximum() {
+    return getMaxRankingsAllowedRaw().equals(MAX_RANKINGS_ALLOWED_NUM_CANDIDATES_OPTION);
+  }
+
+  String getMaxRankingsAllowedAsString() {
+    return getMaxRankingsAllowedRaw();
   }
 
   boolean isBatchEliminationEnabled() {

src/main/java/network/brightspots/rcv/DominionCvrReader.java

@@ -175,8 +175,8 @@ public void runAdditionalValidations(List<CastVoteRecord> castVoteRecords)
   }
 
   @Override
-  public Integer getMaxRankingsAllowed(String contestId) {
-    return contests.get(contestId).getMaxRanks();
+  public boolean isRankingAllowed(int rank, String contestId) {
+    return rank <= contests.get(contestId).getMaxRanks();
   }
 
   private void validateNamesAreInContest(List<CastVoteRecord> castVoteRecords)

src/main/java/network/brightspots/rcv/ResultsWriter.java

@@ -542,7 +542,8 @@ void generateOverallSummaryFiles(
   // returns the filepath written
   String writeGenericCvrCsv(
       List<CastVoteRecord> castVoteRecords,
-      Integer numRanks,
+      CvrSource source,
+      BaseCvrReader reader,
       String csvOutputFolder,
       String inputFilepath,
       String contestId,
@@ -581,7 +582,11 @@ String writeGenericCvrCsv(
       csvPrinter.print("Record Id");
       csvPrinter.print("Precinct");
       csvPrinter.print("Precinct Portion");
-      for (int rank = 1; rank <= numRanks; rank++) {
+      int maxRank = 0;
+      for (CastVoteRecord castVoteRecord : castVoteRecords) {
+        maxRank = Math.max(maxRank, castVoteRecord.candidateRankings.maxRankingNumber());
+      }
+      for (int rank = 1; rank <= maxRank; rank++) {
         String label = String.format("Rank %d", rank);
         csvPrinter.print(label);
       }
@@ -602,7 +607,7 @@ String writeGenericCvrCsv(
         } else {
           csvPrinter.print(castVoteRecord.getPrecinctPortion());
         }
-        printRankings(undeclaredWriteInLabel, numRanks, csvPrinter, castVoteRecord);
+        printRankings(undeclaredWriteInLabel, maxRank, reader, source, csvPrinter, castVoteRecord);
         csvPrinter.println();
       }
       // finalize the file
@@ -624,12 +629,17 @@ String writeGenericCvrCsv(
   private void printRankings(
       String undeclaredWriteInLabel,
       Integer maxRanks,
+      BaseCvrReader reader,
+      CvrSource source,
       CSVPrinter csvPrinter,
       CastVoteRecord castVoteRecord)
       throws IOException {
     // for each rank determine what candidate id, overvote, or undervote occurred and print it
     for (int rank = 1; rank <= maxRanks; rank++) {
       if (castVoteRecord.candidateRankings.hasRankingAt(rank)) {
+        if (reader.isRankingAllowed(rank, source.getContestId())) {
+          break;
+        }
         CandidatesAtRanking candidates = castVoteRecord.candidateRankings.get(rank);
         if (candidates.count() == 1) {
           String selection = candidates.get(0);

src/main/java/network/brightspots/rcv/StreamingCvrReader.java

@@ -166,7 +166,9 @@ private void beginCvr() {
   // complete construction of new CVR object
   private void endCvr() {
     // handle any empty cells which may appear at the end of this row
-    handleEmptyCells(config.getMaxRankingsAllowed() + 1);
+    if (!config.isMaxRankingsSetToMaximum()) {
+      handleEmptyCells(config.getMaxRankingsAllowedWhenNotSetToMaximum() + 1);
+    }
     String computedCastVoteRecordId =
         String.format("%s-%d", ResultsWriter.sanitizeStringForOutput(excelFileName), cvrIndex);
 
@@ -215,7 +217,7 @@ private void cvrCell(int col, String cellData) {
 
     // see if this column is in the ranking range
     if (col >= firstVoteColumnIndex
-        && col < firstVoteColumnIndex + config.getMaxRankingsAllowed()) {
+        && config.isRankingAllowed(col - firstVoteColumnIndex)) {
       int currentRank = col - firstVoteColumnIndex + 1;
       // handle any empty cells which may exist between this cell and any previous one
       handleEmptyCells(currentRank);

src/main/java/network/brightspots/rcv/Tabulator.java

@@ -1132,8 +1132,8 @@ && isCandidateContinuing(cvr.getCurrentRecipientOfVote())) {
         // if this is the last ranking we are out of rankings and must exhaust this cvr
         // determine if the reason is skipping too many ranks, or no continuing candidates
         if (rank == cvr.candidateRankings.maxRankingNumber()) {
-          if (config.getMaxSkippedRanksAllowed() != Integer.MAX_VALUE
-              && config.getMaxRankingsAllowed() - rank > config.getMaxSkippedRanksAllowed()) {
+          if (!config.isMaxRankingsSetToMaximum()
+              && config.getMaxRankingsAllowedWhenNotSetToMaximum() - rank > config.getMaxSkippedRanksAllowed()) {
             recordSelectionForCastVoteRecord(
                 cvr, roundTally, null, StatusForRound.INACTIVE_BY_UNDERVOTE, "");
           } else {

src/main/java/network/brightspots/rcv/TabulatorSession.java

@@ -306,7 +306,8 @@ private List<CastVoteRecord> parseCastVoteRecords(ContestConfig config) {
           this.convertedFilePath =
               writer.writeGenericCvrCsv(
                   castVoteRecords,
-                  reader.getMaxRankingsAllowed(source.getContestId()),
+                  source,
+                  reader,
                   config.getOutputDirectory(),
                   source.getFilePath(),
                   source.getContestId(),