QDoc: Don't write type attributes to index files for macros

QDoc includes a number of attributes when generating index files.
Internally, QDoc uses the `FunctionNode` data structure to represent
invokables. This data structure includes the return type for the
function or method such a node represents. However, not all invokable
entities that are represented internally as a `FunctionNode` carry a
return value. This applies in particular to preprocessor macros in C
and C++.

When generating the index files. QDoc writes an empty `type=""`
attribute for `FunctionNode`s that represent a macro. When reading
the values back in, the value for the `type` attribute defaults to
empty is the attribute is missing. Therefore, writing this out in the
first place leads to unnecessary clutter in the index files.

This change modifies QDoc's behavior such that these attributes are only
written to the index file if they exist. Test data for the
`generatedOutput` test is updated to reflect the new content of the
index files covered by that test.

Task-number: QTBUG-112494
Change-Id: Id6e3a730cbde098068029af1ebf9fa17bd2a4441
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

3 files changed, 12 insertions, 12 deletions

diff --git a/tests/auto/qdoc/generatedoutput/expected_output/html/testqdoc-test.webxml b/tests/auto/qdoc/generatedoutput/expected_output/html/testqdoc-test.webxml
index 565122053..db82eb7e8 100644
--- a/tests/auto/qdoc/generatedoutput/expected_output/html/testqdoc-test.webxml
+++ b/tests/auto/qdoc/generatedoutput/expected_output/html/testqdoc-test.webxml
@@ -5,13 +5,13 @@
             <description>
                 <brief>A class in a namespace.</brief>
             </description>
-            <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" type="" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
+            <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
                 <parameter type="int &amp;" name="x" default=""/>
                 <description>
                     <brief>A macro with argument <argument>x</argument>.</brief>
                 </description>
             </function>
-            <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" type="" signature="Test()">
+            <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" signature="Test()">
                 <description>
                     <para>Default constructor.</para>
                 </description>
diff --git a/tests/auto/qdoc/generatedoutput/expected_output/properties/testcpp.index b/tests/auto/qdoc/generatedoutput/expected_output/properties/testcpp.index
index b9da9fd42..a06a13ae7 100644
--- a/tests/auto/qdoc/generatedoutput/expected_output/properties/testcpp.index
+++ b/tests/auto/qdoc/generatedoutput/expected_output/properties/testcpp.index
@@ -2,8 +2,8 @@
 <!DOCTYPE QDOCINDEX>
 <INDEX url="" title="TestCPP Reference Documentation" version="" project="TestCPP">
     <namespace name="" status="active" access="public" module="testcpp">
-        <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" type="" signature="QDOCTEST_MACRO"/>
-        <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" type="" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
+        <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" signature="QDOCTEST_MACRO"/>
+        <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
             <parameter type="int &amp;" name="x" default=""/>
         </function>
         <page name="autolinking.html" href="autolinking.html" status="active" location="classlists.qdoc" documented="true" subtype="page" title="Autolinking" fulltitle="Autolinking" subtitle="">
@@ -20,12 +20,12 @@
         <page name="https://wiki.qt.io/QProperty" href="https://wiki.qt.io/QProperty" status="active" location="properties.qdoc" documented="true" subtype="externalpage" title="QProperty" fulltitle="QProperty" subtitle=""/>
         <namespace name="TestQDoc" href="testqdoc.html" status="active" access="public" location="testcpp.h" since="2.0" documented="true" module="TestCPP" brief="A namespace">
             <contents name="usage" title="Usage" level="1"/>
-            <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" type="" signature="QDOCTEST_MACRO"/>
+            <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" signature="QDOCTEST_MACRO"/>
             <class name="Test" fullname="TestQDoc::Test" href="testqdoc-test.html" status="active" access="public" location="testcpp.h" since="2.0" documented="true" groups="cpptypes,testgroup" module="TestCPP" brief="A class in a namespace">
-                <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" type="" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
+                <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
                     <parameter type="int &amp;" name="x" default=""/>
                 </function>
-                <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" type="" signature="Test()"/>
+                <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" signature="Test()"/>
                 <function name="anotherObsoleteMember" fullname="TestQDoc::Test::anotherObsoleteMember" href="testqdoc-test-obsolete.html#anotherObsoleteMember" status="deprecated" access="public" location="testcpp.h" documented="true" meta="plain" type="void" signature="void anotherObsoleteMember()"/>
                 <function name="deprecatedMember" fullname="TestQDoc::Test::deprecatedMember" href="testqdoc-test-obsolete.html#deprecatedMember" status="deprecated" access="public" location="testcpp.h" documented="true" meta="plain" type="void" signature="void deprecatedMember()"/>
                 <function name="funcPtr" fullname="TestQDoc::Test::funcPtr" href="testqdoc-test.html#funcPtr" status="active" access="public" location="testcpp.h" documented="true" meta="plain" type="void (*)(bool)" signature="void (*)(bool) funcPtr(bool b, const char *s)">
diff --git a/tests/auto/qdoc/generatedoutput/expected_output/testcpp.index b/tests/auto/qdoc/generatedoutput/expected_output/testcpp.index
index 1fe7eacfa..0808f8a5e 100644
--- a/tests/auto/qdoc/generatedoutput/expected_output/testcpp.index
+++ b/tests/auto/qdoc/generatedoutput/expected_output/testcpp.index
@@ -2,8 +2,8 @@
 <!DOCTYPE QDOCINDEX>
 <INDEX url="" title="TestCPP Reference Documentation" version="" project="TestCPP">
     <namespace name="" status="active" access="public" module="testcpp">
-        <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" type="" signature="QDOCTEST_MACRO"/>
-        <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" type="" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
+        <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" signature="QDOCTEST_MACRO"/>
+        <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
             <parameter type="int &amp;" name="x" default=""/>
         </function>
         <page name="autolinking.html" href="autolinking.html" status="active" location="classlists.qdoc" documented="true" subtype="page" title="Autolinking" fulltitle="Autolinking" subtitle="">
@@ -19,12 +19,12 @@
         </page>
         <namespace name="TestQDoc" href="testqdoc.html" status="active" access="public" location="testcpp.h" since="2.0" documented="true" module="TestCPP" brief="A namespace">
             <contents name="usage" title="Usage" level="1"/>
-            <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" type="" signature="QDOCTEST_MACRO"/>
+            <function name="QDOCTEST_MACRO" href="testqdoc.html#QDOCTEST_MACRO" status="active" access="public" documented="true" related="0" meta="macrowithoutparams" signature="QDOCTEST_MACRO"/>
             <class name="Test" fullname="TestQDoc::Test" href="testqdoc-test.html" status="active" access="public" location="testcpp.h" since="2.0" documented="true" groups="cpptypes,testgroup" module="TestCPP" brief="A class in a namespace">
-                <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" type="" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
+                <function name="QDOCTEST_MACRO2" href="testqdoc-test.html#QDOCTEST_MACRO2" status="active" access="public" documented="true" related="1" since="Test 1.1" meta="macrowithparams" brief="A macro with argument x" signature="QDOCTEST_MACRO2(int &amp;x)" groups="testgroup">
                     <parameter type="int &amp;" name="x" default=""/>
                 </function>
-                <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" type="" signature="Test()"/>
+                <function name="Test" fullname="TestQDoc::Test::Test" href="testqdoc-test.html#Test" status="active" access="public" documented="true" meta="constructor" noexcept="true" signature="Test()"/>
                 <function name="anotherObsoleteMember" fullname="TestQDoc::Test::anotherObsoleteMember" href="testqdoc-test-obsolete.html#anotherObsoleteMember" status="deprecated" access="public" location="testcpp.h" documented="true" meta="plain" type="void" signature="void anotherObsoleteMember()"/>
                 <function name="deprecatedMember" fullname="TestQDoc::Test::deprecatedMember" href="testqdoc-test-obsolete.html#deprecatedMember" status="deprecated" access="public" location="testcpp.h" documented="true" meta="plain" type="void" signature="void deprecatedMember()"/>
                 <function name="funcPtr" fullname="TestQDoc::Test::funcPtr" href="testqdoc-test.html#funcPtr" status="active" access="public" location="testcpp.h" documented="true" meta="plain" type="void (*)(bool)" signature="void (*)(bool) funcPtr(bool b, const char *s)">