From 96661756b1f15a248857b28a861426761ca899e5 Mon Sep 17 00:00:00 2001
From: Lars Hesel Christensen <larshesel.christensen@helvetia.ch>
Date: Fri, 10 Jan 2025 14:36:31 +0100
Subject: [PATCH] Fix sequence numbering in choice with sequences with
 complexTypes

The sequence numbering was resent within the complexType handling and
this change attempts to preserve the sequence numbering across the
elements in the choice alternative handling.
---
 priv/choice_complex/choice_complex.xml |  5 +++++
 priv/choice_complex/choice_complex.xsd | 24 ++++++++++++++++++++++++
 src/erlsom_compile.erl                 | 23 ++++++++++-------------
 test/erlsom_tests.erl                  |  6 ++++++
 4 files changed, 45 insertions(+), 13 deletions(-)
 create mode 100644 priv/choice_complex/choice_complex.xml
 create mode 100644 priv/choice_complex/choice_complex.xsd

diff --git a/priv/choice_complex/choice_complex.xml b/priv/choice_complex/choice_complex.xml
new file mode 100644
index 0000000..8de1595
--- /dev/null
+++ b/priv/choice_complex/choice_complex.xml
@@ -0,0 +1,5 @@
+<ns:L1 xmlns:ns="http://example.com">
+  <E_MAIL>
+    <TEXT>text</TEXT>
+  </E_MAIL>
+</ns:L1>
diff --git a/priv/choice_complex/choice_complex.xsd b/priv/choice_complex/choice_complex.xsd
new file mode 100644
index 0000000..8684eaa
--- /dev/null
+++ b/priv/choice_complex/choice_complex.xsd
@@ -0,0 +1,24 @@
+<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
+	   xmlns="http://example.com"
+	   targetNamespace="http://example.com" elementFormDefault="unqualified"
+	   attributeFormDefault="unqualified">
+  <xs:element name="L1">
+    <xs:complexType>
+      <xs:choice>	
+	<xs:sequence>
+	  <xs:element name="E_MAIL" minOccurs="0" maxOccurs="unbounded">
+	    <xs:complexType>
+	      <xs:sequence>
+		<xs:element name="TEXT" type="xs:string" />
+	      </xs:sequence>
+	    </xs:complexType>
+	  </xs:element>
+	</xs:sequence>
+
+	<xs:sequence>
+          <xs:element name="FLAG" type="xs:boolean" fixed="true" minOccurs="0" />
+	</xs:sequence>
+      </xs:choice>
+    </xs:complexType>
+  </xs:element>
+</xs:schema>
diff --git a/src/erlsom_compile.erl b/src/erlsom_compile.erl
index 42fdc01..2457904 100644
--- a/src/erlsom_compile.erl
+++ b/src/erlsom_compile.erl
@@ -784,24 +784,21 @@ isAny(#alt{tag = '#any', anyInfo = #anyInfo{prCont = "lax", ns = "##any"}}) ->
 isAny(_) ->
   false.
 
-%% TODO: seqCnt should be passed from one element to the next, but not down into the
-%% tree (it should be reset to 0) (the first sequence-in-sequnce should always have nr. 1).
-%% -record(localElementType, {name, type, ref, minOccurs, maxOccurs, simpleOrComplex}).
 translateSequence([LocalElement = #localElementType{} |Tail], ElementsSoFar, Acc) ->
-  {Element, Acc2} = translateLocalElement(LocalElement, Acc),
-  translateSequence(Tail, [Element | ElementsSoFar], Acc2);
+  {Element, Acc2} = translateLocalElement(LocalElement, Acc#p1acc{seqCnt = 0}),
+  translateSequence(Tail, [Element | ElementsSoFar], Acc2#p1acc{seqCnt = Acc#p1acc.seqCnt});
 translateSequence([ChoiceElement = #choiceType{} |Tail], ElementsSoFar, Acc) ->
-  {Element, Acc2} = translateElement(ChoiceElement, Acc),
-  translateSequence(Tail, [Element | ElementsSoFar], Acc2);
+  {Element, Acc2} = translateElement(ChoiceElement, Acc#p1acc{seqCnt = 0}),
+  translateSequence(Tail, [Element | ElementsSoFar], Acc2#p1acc{seqCnt = Acc#p1acc.seqCnt});
 translateSequence([AnyElement = #anyType{} |Tail], ElementsSoFar, Acc) ->
-  {Element, Acc2} = translateElement(AnyElement, Acc),
-  translateSequence(Tail, [Element | ElementsSoFar], Acc2);
+  {Element, Acc2} = translateElement(AnyElement, Acc#p1acc{seqCnt = 0}),
+  translateSequence(Tail, [Element | ElementsSoFar], Acc2#p1acc{seqCnt = Acc#p1acc.seqCnt});
 translateSequence([GroupElement = #groupRefType{} |Tail], ElementsSoFar, Acc) ->
-  {Element, Acc2} = translateElement(GroupElement, Acc),
-  translateSequence(Tail, [Element | ElementsSoFar], Acc2);
+  {Element, Acc2} = translateElement(GroupElement, Acc#p1acc{seqCnt = 0}),
+  translateSequence(Tail, [Element | ElementsSoFar], Acc2#p1acc{seqCnt = Acc#p1acc.seqCnt});
 translateSequence([SequenceElement = #sequenceType{} | Tail], ElementsSoFar, Acc) ->
-  {Element, Acc2} = translateSequenceInSequence(SequenceElement, Acc),
-  translateSequence(Tail, [Element | ElementsSoFar], Acc2);
+  {Element, Acc2} = translateSequenceInSequence(SequenceElement, Acc#p1acc{seqCnt = 0}),
+  translateSequence(Tail, [Element | ElementsSoFar], Acc2#p1acc{seqCnt = Acc#p1acc.seqCnt});
 
 translateSequence(undefined, ElementsSoFar, Acc) ->
   {lists:reverse(ElementsSoFar), Acc};
diff --git a/test/erlsom_tests.erl b/test/erlsom_tests.erl
index b849829..14f8443 100644
--- a/test/erlsom_tests.erl
+++ b/test/erlsom_tests.erl
@@ -151,3 +151,9 @@ xsi_type_no_prefix_read_test() ->
     ?assertMatch({'ExtType', _, "base", "ext"}, Parsed).
 
 
+choice_complex_test() ->
+    {ok, Xsd} = file:read_file(priv_path(["choice_complex", "choice_complex.xsd"])),
+    {ok, Xml} = file:read_file(priv_path(["choice_complex", "choice_complex.xml"])),
+    {ok, Model} = erlsom:compile(Xsd),
+    {ok, _Data, _} = erlsom:scan(Xml, Model).
+