From ba0aa7c2a822bd23a9b2ec5af07265bc3eba86ce Mon Sep 17 00:00:00 2001
From: Jim Jones <jim.jones@uni-muenster.de>
Date: Fri, 6 Sep 2024 23:48:24 +0200
Subject: [PATCH v2 2/2] Bug fix: remove default trailing newline from
 XMLSERIALIZE calls

xmlDocContentDumpOutput adds by default a trailing newline to
DOCUMENT typed XML strings when XMLSERIALIZE is called with the
option INDENT. This introduces a condition that checks if the
serialized DOCUMENT contains a trailing newline and if so removes
it. Regression tests were updated accordingly.
---
 src/backend/utils/adt/xml.c         | 18 +++++++++++++++++-
 src/test/regress/expected/xml.out   | 18 ++++++------------
 src/test/regress/expected/xml_2.out | 18 ++++++------------
 3 files changed, 29 insertions(+), 25 deletions(-)

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 1cd4929870..fa38d2b992 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -808,7 +808,23 @@ xmltotext_with_options(xmltype *data, XmlOptionType xmloption_arg, bool indent)
 						"could not close xmlSaveCtxtPtr");
 		}
 
-		result = (text *) xmlBuffer_to_xmltype(buf);
+		/*
+		 * xmlDocContentDumpOutput adds a trailing newline by default
+		 * so we get rid of it here.
+		 */
+		if (xmloption_arg == XMLOPTION_DOCUMENT)
+		{
+			char *str = (char *) xmlBufferContent(buf);
+			int len = xmlBufferLength(buf);
+
+			while (len > 0 && (str[len - 1] == '\n' ||
+								str[len - 1] == '\r'))
+				str[--len] = '\0';
+
+			result = cstring_to_text_with_len(str, len);
+		}
+		else
+			result = (text *) xmlBuffer_to_xmltype(buf);
 	}
 	PG_CATCH();
 	{
diff --git a/src/test/regress/expected/xml.out b/src/test/regress/expected/xml.out
index 6f073101a1..361a6f9b27 100644
--- a/src/test/regress/expected/xml.out
+++ b/src/test/regress/expected/xml.out
@@ -485,8 +485,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar><val x="y">42</val></bar></foo>' AS text
    <bar>                +
      <val x="y">42</val>+
    </bar>               +
- </foo>                 +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar><val x="y">42</val></bar></foo>' AS text INDENT);
@@ -546,8 +545,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar><val x="y">42</val><val x="y">text node<
      <val x="y">42</val>                    +
      <val x="y">text node<val>73</val></val>+
    </bar>                                   +
- </foo>                                     +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar><val x="y">42</val><val x="y">text node<val>73</val></val></bar></foo>' AS text INDENT);
@@ -601,8 +599,7 @@ SELECT xmlserialize(DOCUMENT '<?xml version="1.0" encoding="UTF-8"?><foo><bar><v
    <bar>                               +
      <val>73</val>                     +
    </bar>                              +
- </foo>                                +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<?xml version="1.0" encoding="UTF-8"?><foo><bar><val>73</val></bar></foo>' AS text INDENT);
@@ -620,8 +617,7 @@ SELECT xmlserialize(DOCUMENT '<!DOCTYPE a><a/>' AS text INDENT);
  xmlserialize 
 --------------
  <!DOCTYPE a>+
- <a/>        +
- 
+ <a/>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<!DOCTYPE a><a/>' AS text INDENT);
@@ -638,8 +634,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar></bar></foo>' AS text INDENT);
 --------------
  <foo>       +
    <bar/>    +
- </foo>      +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar></bar></foo>' AS text INDENT);
@@ -669,8 +664,7 @@ SELECT xmlserialize(DOCUMENT '<foo>   <bar></bar>    </foo>' AS text INDENT);
 --------------
  <foo>       +
    <bar/>    +
- </foo>      +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  'text node<foo>    <bar></bar>   </foo>' AS text INDENT);
diff --git a/src/test/regress/expected/xml_2.out b/src/test/regress/expected/xml_2.out
index 7b154da4ba..73c2851d3f 100644
--- a/src/test/regress/expected/xml_2.out
+++ b/src/test/regress/expected/xml_2.out
@@ -471,8 +471,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar><val x="y">42</val></bar></foo>' AS text
    <bar>                +
      <val x="y">42</val>+
    </bar>               +
- </foo>                 +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar><val x="y">42</val></bar></foo>' AS text INDENT);
@@ -532,8 +531,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar><val x="y">42</val><val x="y">text node<
      <val x="y">42</val>                    +
      <val x="y">text node<val>73</val></val>+
    </bar>                                   +
- </foo>                                     +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar><val x="y">42</val><val x="y">text node<val>73</val></val></bar></foo>' AS text INDENT);
@@ -587,8 +585,7 @@ SELECT xmlserialize(DOCUMENT '<?xml version="1.0" encoding="UTF-8"?><foo><bar><v
    <bar>                               +
      <val>73</val>                     +
    </bar>                              +
- </foo>                                +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<?xml version="1.0" encoding="UTF-8"?><foo><bar><val>73</val></bar></foo>' AS text INDENT);
@@ -606,8 +603,7 @@ SELECT xmlserialize(DOCUMENT '<!DOCTYPE a><a/>' AS text INDENT);
  xmlserialize 
 --------------
  <!DOCTYPE a>+
- <a/>        +
- 
+ <a/>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<!DOCTYPE a><a/>' AS text INDENT);
@@ -624,8 +620,7 @@ SELECT xmlserialize(DOCUMENT '<foo><bar></bar></foo>' AS text INDENT);
 --------------
  <foo>       +
    <bar/>    +
- </foo>      +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  '<foo><bar></bar></foo>' AS text INDENT);
@@ -655,8 +650,7 @@ SELECT xmlserialize(DOCUMENT '<foo>   <bar></bar>    </foo>' AS text INDENT);
 --------------
  <foo>       +
    <bar/>    +
- </foo>      +
- 
+ </foo>
 (1 row)
 
 SELECT xmlserialize(CONTENT  'text node<foo>    <bar></bar>   </foo>' AS text INDENT);
-- 
2.34.1