java/com/google/gerrit/server/notedb/ChangeNotesParseApprovalUtil.java - gerrit/ - Git at Google

 // Copyright (C) 2022 The Android Open Source Project
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 package com.google.gerrit.server.notedb;

 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_COPIED_LABEL;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_LABEL;

 import com.google.auto.value.AutoValue;
 import com.google.common.base.Splitter;
 import com.google.common.base.Strings;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.revwalk.FooterKey;

 /**
  * Util to extract {@link com.google.gerrit.entities.PatchSetApproval} from {@link
  * ChangeNoteFooters#FOOTER_LABEL} or {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}.
  */
 public class ChangeNotesParseApprovalUtil {
   private static final String LABEL_VOTE_UUID_SEPARATOR = ", ";

   /**
    * {@link com.google.gerrit.entities.PatchSetApproval}, parsed from {@link
    * ChangeNoteFooters#FOOTER_LABEL} or {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}.
    *
    * <p>In comparison to {@link com.google.gerrit.entities.PatchSetApproval}, this entity represent
    * the raw fields, parsed from the NoteDB footer line, without any interpretation of the parsed
    * values. See {@link #parseApproval} and {@link #parseCopiedApproval} for the valid {@link
    * #footerLine} values.
    */
   @AutoValue
   public abstract static class ParsedPatchSetApproval {

     /** The original footer value, that this entity was parsed from. */
     public abstract String footerLine();

     public abstract boolean isRemoval();

     /** Either <LABEL>=VOTE or <LABEL> for {@link #isRemoval}. */
     public abstract String labelVote();

     public abstract Optional<String> uuid();

     public abstract Optional<String> accountIdent();

     public abstract Optional<String> realAccountIdent();

     public abstract Optional<String> tag();

     public static Builder builder() {
       return new AutoValue_ChangeNotesParseApprovalUtil_ParsedPatchSetApproval.Builder();
     }

     @AutoValue.Builder
     public abstract static class Builder {

       abstract Builder footerLine(String labelLine);

       abstract Builder isRemoval(boolean isRemoval);

       abstract Builder labelVote(String labelVote);

       abstract Builder uuid(Optional<String> uuid);

       abstract Builder accountIdent(Optional<String> accountIdent);

       abstract Builder realAccountIdent(Optional<String> realAccountIdent);

       abstract Builder tag(Optional<String> tag);

       abstract ParsedPatchSetApproval build();
     }
   }

   /**
    * Delegates parsing of {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL}
    * line to dedicated methods: {@link #parseAddedApproval} and {@link #parseRemovedApproval}
    * correspondingly.
    */
   public static ParsedPatchSetApproval parseApproval(String footerLine)
       throws ConfigInvalidException {
     try {
       return footerLine.startsWith("-")
           ? parseRemovedApproval(footerLine)
           : parseAddedApproval(footerLine);
     } catch (StringIndexOutOfBoundsException ex) {
       throw parseException(FOOTER_LABEL, footerLine, ex);
     }
   }

   /**
    * Parses added {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL} line.
    *
    * <p>Valid added approval footer examples:
    *
    * <ul>
    *   <li>Label: &lt;LABEL&gt;=VOTE
    *   <li>Label: &lt;LABEL&gt;=VOTE &lt;Gerrit Account&gt;
    *   <li>Label: &lt;LABEL&gt;=VOTE, &lt;UUID&gt;
    *   <li>Label: &lt;LABEL&gt;=VOTE, &lt;UUID&gt; &lt;Gerrit Account&gt;
    * </ul>
    *
    * <p>&lt;UUID&gt; is optional, since the approval might have been granted before {@link
    * com.google.gerrit.entities.PatchSetApproval.UUID} was introduced.
    *
    * <p><Gerrit Account> is only persisted in cases, when the account, that granted the vote does
    * not match the account, that issued {@link ChangeUpdate} (created this NoteDB commit).
    */
   private static ParsedPatchSetApproval parseAddedApproval(String footerLine)
       throws ConfigInvalidException {
     ParsedPatchSetApproval.Builder rawPatchSetApproval =
         ParsedPatchSetApproval.builder().footerLine(footerLine);
     rawPatchSetApproval.isRemoval(false);
     // We need some additional logic to differentiate between labels that have a UUID and those that
     // have a user with a comma. This allows us to separate the following cases (note that the
     // leading `Label: ` has been elided at this point):
     //   Label: <LABEL>=VOTE, <UUID> <Gerrit Account>
     //   Label: <LABEL>=VOTE <Gerrit, Account>
     int reviewerStartOffset = 0;
     int scoreStart = footerLine.indexOf('=') + 1;
     StringBuilder labelNameScore = new StringBuilder(footerLine.substring(0, scoreStart));
     for (int i = scoreStart; i < footerLine.length(); i++) {
       char currentChar = footerLine.charAt(i);

       // If we hit ',' before ' ' we have a UUID
       if (currentChar == ',') {
         labelNameScore.append(footerLine, scoreStart, i);
         int uuidStart = i + LABEL_VOTE_UUID_SEPARATOR.length();
         int uuidEnd = footerLine.indexOf(' ', uuidStart);
         String uuid = footerLine.substring(uuidStart, uuidEnd > 0 ? uuidEnd : footerLine.length());
         checkFooter(!Strings.isNullOrEmpty(uuid), FOOTER_LABEL, footerLine);
         rawPatchSetApproval.uuid(Optional.of(uuid));
         reviewerStartOffset = uuidStart + uuid.length();
         break;
       }

       // Otherwise we don't
       if (currentChar == ' ') {
         labelNameScore.append(footerLine, scoreStart, i);
         break;
       }

       // If we hit neither we're defensive assign the whole line
       if (i == footerLine.length() - 1) {
         labelNameScore = new StringBuilder(footerLine);
         break;
       }
     }

     rawPatchSetApproval.labelVote(labelNameScore.toString());

     int reviewerStart = footerLine.indexOf(' ', reviewerStartOffset);
     if (reviewerStart > 0) {
       String ident = footerLine.substring(reviewerStart + 1);
       rawPatchSetApproval.accountIdent(Optional.of(ident));
     }
     return rawPatchSetApproval.build();
   }

   /**
    * Parses removed {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL} line.
    *
    * <p>Valid removed approval footer examples:
    *
    * <ul>
    *   <li>-&lt;LABEL&gt;
    *   <li>-&lt;LABEL&gt; &lt;Gerrit Account&gt;
    * </ul>
    *
    * <p>&lt;Gerrit Account&gt; is only persisted in cases, when the account, that granted the vote
    * does not match the account, that issued {@link ChangeUpdate} (created this NoteDB commit).
    */
   private static ParsedPatchSetApproval parseRemovedApproval(String footerLine) {
     ParsedPatchSetApproval.Builder rawPatchSetApproval =
         ParsedPatchSetApproval.builder().footerLine(footerLine);
     rawPatchSetApproval.isRemoval(true);
     int labelStart = 1;
     int reviewerStart = footerLine.indexOf(' ', labelStart);

     rawPatchSetApproval.labelVote(
         reviewerStart != -1
             ? footerLine.substring(labelStart, reviewerStart)
             : footerLine.substring(labelStart));

     if (reviewerStart > 0) {
       String ident = footerLine.substring(reviewerStart + 1);
       rawPatchSetApproval.accountIdent(Optional.of(ident));
     }
     return rawPatchSetApproval.build();
   }

   /**
    * Parses copied {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}
    * line.
    *
    * <p>Footer example: Copied-Label: <LABEL>=VOTE, <UUID> <Gerrit Account>,<Gerrit Real Account>
    * :"<TAG>"
    *
    * <ul>
    *   <li>":<"TAG>"" is optional.
    *   <li><Gerrit Real Account> is also optional, if it was not set.
    *   <li><UUID> is optional, since the approval might have been granted before {@link
    *       com.google.gerrit.entities.PatchSetApproval.UUID} was introduced.
    *   <li>The label, vote, and the Gerrit account are mandatory (unlike FOOTER_LABEL where Gerrit
    *       Account is also optional since by default it's the committer).
    * </ul>
    *
    * <p>Footer example for removal: Copied-Label: -<LABEL> <Gerrit Account>,<Gerrit Real Account>
    *
    * <ul>
    *   <li><Gerrit Real Account> is also optional, if it was not set.
    * </ul>
    */
   public static ParsedPatchSetApproval parseCopiedApproval(String labelLine)
       throws ConfigInvalidException {
     try {
       ParsedPatchSetApproval.Builder rawPatchSetApproval =
           ParsedPatchSetApproval.builder().footerLine(labelLine);

       boolean isRemoval = labelLine.startsWith("-");
       rawPatchSetApproval.isRemoval(isRemoval);
       int labelStart = isRemoval ? 1 : 0;
       int tagStart = isRemoval ? -1 : labelLine.indexOf(":\"");
       int uuidStart = parseCopiedApprovalUuidStart(labelLine, tagStart);

       checkFooter(!isRemoval || uuidStart == -1, FOOTER_LABEL, labelLine);

       // Weird tag that contains uuid delimiter. The uuid is actually not present.
       if (tagStart != -1 && uuidStart > tagStart) {
         uuidStart = -1;
       }

       int identitiesStart =
           labelLine.indexOf(
               ' ', uuidStart != -1 ? uuidStart + LABEL_VOTE_UUID_SEPARATOR.length() : 0);
       checkFooter(
           identitiesStart != -1 && identitiesStart < labelLine.length(),
           FOOTER_COPIED_LABEL,
           labelLine);

       String labelVoteStr =
           labelLine.substring(labelStart, uuidStart != -1 ? uuidStart : identitiesStart);
       rawPatchSetApproval.labelVote(labelVoteStr);
       if (uuidStart != -1) {
         String uuid = labelLine.substring(uuidStart + 2, identitiesStart);
         checkFooter(!Strings.isNullOrEmpty(uuid), FOOTER_COPIED_LABEL, labelLine);
         rawPatchSetApproval.uuid(Optional.of(uuid));
       }
       // The first account is the accountId, and second (if applicable) is the realAccountId.
       List<String> identities =
           parseIdentities(
               labelLine.substring(
                   identitiesStart + 1, tagStart == -1 ? labelLine.length() : tagStart));

       rawPatchSetApproval.accountIdent(Optional.of(identities.get(0)));

       if (identities.size() > 1) {
         rawPatchSetApproval.realAccountIdent(Optional.of(identities.get(1)));
       }

       if (tagStart != -1) {
         // tagStart+2 skips ":\"" to parse the actual tag. Tags are in brackets.
         // line.length()-1 skips the last ".
         String tag = labelLine.substring(tagStart + 2, labelLine.length() - 1);
         rawPatchSetApproval.tag(Optional.of(tag));
       }
       return rawPatchSetApproval.build();
     } catch (StringIndexOutOfBoundsException ex) {
       throw parseException(FOOTER_COPIED_LABEL, labelLine, ex);
     }
   }

   // Return the UUID start index or -1 if no UUID is present
   private static int parseCopiedApprovalUuidStart(String line, int tagStart) {
     int separatorIndex = line.indexOf(LABEL_VOTE_UUID_SEPARATOR);

     // The first part of the condition checks whether the footer has the following format:
     //   Copied-Label: <LABEL>=VOTE <Gerrit Account>,<Gerrit Real Account> :"<TAG>"
     //   Weird tag that contains uuid delimiter. The uuid is actually not present.
     if ((tagStart != -1 && separatorIndex > tagStart)
         ||

         // The second part of the condition allows us to distinguish the following two lines:
         //   Label2=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>
         //   Label2=+1 User Name (company_name, department) <2@gerrit>
         (line.indexOf(' ') < separatorIndex)) {
       return -1;
     }
     return separatorIndex;
   }

   // Splitting on "," breaks for identities containing commas. The below re-implements splitting on
   // "(?<=>),", but it's 3-5x faster, as performance matters here.
   private static List<String> parseIdentities(String line) {
     List<String> idents = Splitter.on(',').splitToList(line);
     List<String> identitiesList = new ArrayList<>();
     for (int i = 0; i < idents.size(); i++) {
       if (i == 0 || idents.get(i - 1).endsWith(">")) {
         identitiesList.add(idents.get(i));
       } else {
         int lastIndex = identitiesList.size() - 1;
         identitiesList.set(lastIndex, identitiesList.get(lastIndex) + "," + idents.get(i));
       }
     }
     return identitiesList;
   }

   private static void checkFooter(boolean expr, FooterKey footer, String actual)
       throws ConfigInvalidException {
     if (!expr) {
       throw parseException(footer, actual, /*cause=*/ null);
     }
   }

   private static ConfigInvalidException parseException(
       FooterKey footer, String actual, Throwable cause) {
     return new ConfigInvalidException(
         String.format("invalid %s: %s", footer.getName(), actual), cause);
   }
 }
	// Copyright (C) 2022 The Android Open Source Project
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	package com.google.gerrit.server.notedb;

	import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_COPIED_LABEL;
	import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_LABEL;

	import com.google.auto.value.AutoValue;
	import com.google.common.base.Splitter;
	import com.google.common.base.Strings;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.Optional;
	import org.eclipse.jgit.errors.ConfigInvalidException;
	import org.eclipse.jgit.revwalk.FooterKey;

	/**
	* Util to extract {@link com.google.gerrit.entities.PatchSetApproval} from {@link
	* ChangeNoteFooters#FOOTER_LABEL} or {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}.
	*/
	public class ChangeNotesParseApprovalUtil {
	private static final String LABEL_VOTE_UUID_SEPARATOR = ", ";

	/**
	* {@link com.google.gerrit.entities.PatchSetApproval}, parsed from {@link
	* ChangeNoteFooters#FOOTER_LABEL} or {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}.
	*
	* <p>In comparison to {@link com.google.gerrit.entities.PatchSetApproval}, this entity represent
	* the raw fields, parsed from the NoteDB footer line, without any interpretation of the parsed
	* values. See {@link #parseApproval} and {@link #parseCopiedApproval} for the valid {@link
	* #footerLine} values.
	*/
	@AutoValue
	public abstract static class ParsedPatchSetApproval {

	/** The original footer value, that this entity was parsed from. */
	public abstract String footerLine();

	public abstract boolean isRemoval();

	/** Either <LABEL>=VOTE or <LABEL> for {@link #isRemoval}. */
	public abstract String labelVote();

	public abstract Optional<String> uuid();

	public abstract Optional<String> accountIdent();

	public abstract Optional<String> realAccountIdent();

	public abstract Optional<String> tag();

	public static Builder builder() {
	return new AutoValue_ChangeNotesParseApprovalUtil_ParsedPatchSetApproval.Builder();
	}

	@AutoValue.Builder
	public abstract static class Builder {

	abstract Builder footerLine(String labelLine);

	abstract Builder isRemoval(boolean isRemoval);

	abstract Builder labelVote(String labelVote);

	abstract Builder uuid(Optional<String> uuid);

	abstract Builder accountIdent(Optional<String> accountIdent);

	abstract Builder realAccountIdent(Optional<String> realAccountIdent);

	abstract Builder tag(Optional<String> tag);

	abstract ParsedPatchSetApproval build();
	}
	}

	/**
	* Delegates parsing of {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL}
	* line to dedicated methods: {@link #parseAddedApproval} and {@link #parseRemovedApproval}
	* correspondingly.
	*/
	public static ParsedPatchSetApproval parseApproval(String footerLine)
	throws ConfigInvalidException {
	try {
	return footerLine.startsWith("-")
	? parseRemovedApproval(footerLine)
	: parseAddedApproval(footerLine);
	} catch (StringIndexOutOfBoundsException ex) {
	throw parseException(FOOTER_LABEL, footerLine, ex);
	}
	}

	/**
	* Parses added {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL} line.
	*
	* <p>Valid added approval footer examples:
	*
	* <ul>
	* <li>Label: <LABEL>=VOTE
	* <li>Label: <LABEL>=VOTE <Gerrit Account>
	* <li>Label: <LABEL>=VOTE, <UUID>
	* <li>Label: <LABEL>=VOTE, <UUID> <Gerrit Account>
	* </ul>
	*
	* <p><UUID> is optional, since the approval might have been granted before {@link
	* com.google.gerrit.entities.PatchSetApproval.UUID} was introduced.
	*
	* <p><Gerrit Account> is only persisted in cases, when the account, that granted the vote does
	* not match the account, that issued {@link ChangeUpdate} (created this NoteDB commit).
	*/
	private static ParsedPatchSetApproval parseAddedApproval(String footerLine)
	throws ConfigInvalidException {
	ParsedPatchSetApproval.Builder rawPatchSetApproval =
	ParsedPatchSetApproval.builder().footerLine(footerLine);
	rawPatchSetApproval.isRemoval(false);
	// We need some additional logic to differentiate between labels that have a UUID and those that
	// have a user with a comma. This allows us to separate the following cases (note that the
	// leading `Label: ` has been elided at this point):
	// Label: <LABEL>=VOTE, <UUID> <Gerrit Account>
	// Label: <LABEL>=VOTE <Gerrit, Account>
	int reviewerStartOffset = 0;
	int scoreStart = footerLine.indexOf('=') + 1;
	StringBuilder labelNameScore = new StringBuilder(footerLine.substring(0, scoreStart));
	for (int i = scoreStart; i < footerLine.length(); i++) {
	char currentChar = footerLine.charAt(i);

	// If we hit ',' before ' ' we have a UUID
	if (currentChar == ',') {
	labelNameScore.append(footerLine, scoreStart, i);
	int uuidStart = i + LABEL_VOTE_UUID_SEPARATOR.length();
	int uuidEnd = footerLine.indexOf(' ', uuidStart);
	String uuid = footerLine.substring(uuidStart, uuidEnd > 0 ? uuidEnd : footerLine.length());
	checkFooter(!Strings.isNullOrEmpty(uuid), FOOTER_LABEL, footerLine);
	rawPatchSetApproval.uuid(Optional.of(uuid));
	reviewerStartOffset = uuidStart + uuid.length();
	break;
	}

	// Otherwise we don't
	if (currentChar == ' ') {
	labelNameScore.append(footerLine, scoreStart, i);
	break;
	}

	// If we hit neither we're defensive assign the whole line
	if (i == footerLine.length() - 1) {
	labelNameScore = new StringBuilder(footerLine);
	break;
	}
	}

	rawPatchSetApproval.labelVote(labelNameScore.toString());

	int reviewerStart = footerLine.indexOf(' ', reviewerStartOffset);
	if (reviewerStart > 0) {
	String ident = footerLine.substring(reviewerStart + 1);
	rawPatchSetApproval.accountIdent(Optional.of(ident));
	}
	return rawPatchSetApproval.build();
	}

	/**
	* Parses removed {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_LABEL} line.
	*
	* <p>Valid removed approval footer examples:
	*
	* <ul>
	* <li>-<LABEL>
	* <li>-<LABEL> <Gerrit Account>
	* </ul>
	*
	* <p><Gerrit Account> is only persisted in cases, when the account, that granted the vote
	* does not match the account, that issued {@link ChangeUpdate} (created this NoteDB commit).
	*/
	private static ParsedPatchSetApproval parseRemovedApproval(String footerLine) {
	ParsedPatchSetApproval.Builder rawPatchSetApproval =
	ParsedPatchSetApproval.builder().footerLine(footerLine);
	rawPatchSetApproval.isRemoval(true);
	int labelStart = 1;
	int reviewerStart = footerLine.indexOf(' ', labelStart);

	rawPatchSetApproval.labelVote(
	reviewerStart != -1
	? footerLine.substring(labelStart, reviewerStart)
	: footerLine.substring(labelStart));

	if (reviewerStart > 0) {
	String ident = footerLine.substring(reviewerStart + 1);
	rawPatchSetApproval.accountIdent(Optional.of(ident));
	}
	return rawPatchSetApproval.build();
	}

	/**
	* Parses copied {@link ParsedPatchSetApproval} from {@link ChangeNoteFooters#FOOTER_COPIED_LABEL}
	* line.
	*
	* <p>Footer example: Copied-Label: <LABEL>=VOTE, <UUID> <Gerrit Account>,<Gerrit Real Account>
	* :"<TAG>"
	*
	* <ul>
	* <li>":<"TAG>"" is optional.
	* <li><Gerrit Real Account> is also optional, if it was not set.
	* <li><UUID> is optional, since the approval might have been granted before {@link
	* com.google.gerrit.entities.PatchSetApproval.UUID} was introduced.
	* <li>The label, vote, and the Gerrit account are mandatory (unlike FOOTER_LABEL where Gerrit
	* Account is also optional since by default it's the committer).
	* </ul>
	*
	* <p>Footer example for removal: Copied-Label: -<LABEL> <Gerrit Account>,<Gerrit Real Account>
	*
	* <ul>
	* <li><Gerrit Real Account> is also optional, if it was not set.
	* </ul>
	*/
	public static ParsedPatchSetApproval parseCopiedApproval(String labelLine)
	throws ConfigInvalidException {
	try {
	ParsedPatchSetApproval.Builder rawPatchSetApproval =
	ParsedPatchSetApproval.builder().footerLine(labelLine);

	boolean isRemoval = labelLine.startsWith("-");
	rawPatchSetApproval.isRemoval(isRemoval);
	int labelStart = isRemoval ? 1 : 0;
	int tagStart = isRemoval ? -1 : labelLine.indexOf(":\"");
	int uuidStart = parseCopiedApprovalUuidStart(labelLine, tagStart);

	checkFooter(!isRemoval \|\| uuidStart == -1, FOOTER_LABEL, labelLine);

	// Weird tag that contains uuid delimiter. The uuid is actually not present.
	if (tagStart != -1 && uuidStart > tagStart) {
	uuidStart = -1;
	}

	int identitiesStart =
	labelLine.indexOf(
	' ', uuidStart != -1 ? uuidStart + LABEL_VOTE_UUID_SEPARATOR.length() : 0);
	checkFooter(
	identitiesStart != -1 && identitiesStart < labelLine.length(),
	FOOTER_COPIED_LABEL,
	labelLine);

	String labelVoteStr =
	labelLine.substring(labelStart, uuidStart != -1 ? uuidStart : identitiesStart);
	rawPatchSetApproval.labelVote(labelVoteStr);
	if (uuidStart != -1) {
	String uuid = labelLine.substring(uuidStart + 2, identitiesStart);
	checkFooter(!Strings.isNullOrEmpty(uuid), FOOTER_COPIED_LABEL, labelLine);
	rawPatchSetApproval.uuid(Optional.of(uuid));
	}
	// The first account is the accountId, and second (if applicable) is the realAccountId.
	List<String> identities =
	parseIdentities(
	labelLine.substring(
	identitiesStart + 1, tagStart == -1 ? labelLine.length() : tagStart));

	rawPatchSetApproval.accountIdent(Optional.of(identities.get(0)));

	if (identities.size() > 1) {
	rawPatchSetApproval.realAccountIdent(Optional.of(identities.get(1)));
	}

	if (tagStart != -1) {
	// tagStart+2 skips ":\"" to parse the actual tag. Tags are in brackets.
	// line.length()-1 skips the last ".
	String tag = labelLine.substring(tagStart + 2, labelLine.length() - 1);
	rawPatchSetApproval.tag(Optional.of(tag));
	}
	return rawPatchSetApproval.build();
	} catch (StringIndexOutOfBoundsException ex) {
	throw parseException(FOOTER_COPIED_LABEL, labelLine, ex);
	}
	}

	// Return the UUID start index or -1 if no UUID is present
	private static int parseCopiedApprovalUuidStart(String line, int tagStart) {
	int separatorIndex = line.indexOf(LABEL_VOTE_UUID_SEPARATOR);

	// The first part of the condition checks whether the footer has the following format:
	// Copied-Label: <LABEL>=VOTE <Gerrit Account>,<Gerrit Real Account> :"<TAG>"
	// Weird tag that contains uuid delimiter. The uuid is actually not present.
	if ((tagStart != -1 && separatorIndex > tagStart)
	\|\|

	// The second part of the condition allows us to distinguish the following two lines:
	// Label2=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>
	// Label2=+1 User Name (company_name, department) <2@gerrit>
	(line.indexOf(' ') < separatorIndex)) {
	return -1;
	}
	return separatorIndex;
	}

	// Splitting on "," breaks for identities containing commas. The below re-implements splitting on
	// "(?<=>),", but it's 3-5x faster, as performance matters here.
	private static List<String> parseIdentities(String line) {
	List<String> idents = Splitter.on(',').splitToList(line);
	List<String> identitiesList = new ArrayList<>();
	for (int i = 0; i < idents.size(); i++) {
	if (i == 0 \|\| idents.get(i - 1).endsWith(">")) {
	identitiesList.add(idents.get(i));
	} else {
	int lastIndex = identitiesList.size() - 1;
	identitiesList.set(lastIndex, identitiesList.get(lastIndex) + "," + idents.get(i));
	}
	}
	return identitiesList;
	}

	private static void checkFooter(boolean expr, FooterKey footer, String actual)
	throws ConfigInvalidException {
	if (!expr) {
	throw parseException(footer, actual, /cause=/ null);
	}
	}

	private static ConfigInvalidException parseException(
	FooterKey footer, String actual, Throwable cause) {
	return new ConfigInvalidException(
	String.format("invalid %s: %s", footer.getName(), actual), cause);
	}
	}