loplugin:stringadd look for unnecessary temporaries

which defeat the *StringConcat optimisation.
Also make StringConcat conversions treat a nullptr as an empty string,
to match the O*String(char*) constructors.

Change-Id: If45f5b4b6a535c97bfeeacd9ec472a7603a52e5b
Reviewed-on: https://gerrit.libreoffice.org/80724
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 15 insertions, 14 deletions

diff --git a/test/source/sheet/xsheetauditing.cxx b/test/source/sheet/xsheetauditing.cxx
index 3e832413ffe4..61e96d09d92f 100644
--- a/test/source/sheet/xsheetauditing.cxx
+++ b/test/source/sheet/xsheetauditing.cxx
@@ -87,7 +87,8 @@ void XSheetAuditing::testShowErrors()
     uno::Reference<sheet::XSpreadsheet> xSheet(xAuditing, UNO_QUERY_THROW);
     uno::Reference<table::XCell> xCell = xSheet->getCellByPosition(7, 6);
     xCell->setValue(-9);
-    xCell->setFormula("=SQRT(" + OUString(static_cast<char>('A' + 7)) + OUString::number(7) + ")");
+    xCell->setFormula("=SQRT(" + OUStringLiteral1(static_cast<char>('A' + 7)) + OUString::number(7)
+                      + ")");
 
     uno::Reference<text::XText> xText(xCell, UNO_QUERY_THROW);
     CPPUNIT_ASSERT_EQUAL_MESSAGE("No error code", OUString("Err:522"), xText->getString());
diff --git a/test/source/xmltesttools.cxx b/test/source/xmltesttools.cxx
index 4b0ba89de7d4..38420ba384d2 100644
--- a/test/source/xmltesttools.cxx
+++ b/test/source/xmltesttools.cxx
@@ -82,7 +82,7 @@ OUString XmlTestTools::getXPath(xmlDocPtr pXmlDoc, const OString& rXPath, const
     CPPUNIT_ASSERT(pXmlDoc);
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
                                  1, xmlXPathNodeSetGetLength(pXmlNodes));
     if (rAttribute.isEmpty())
     {
@@ -91,7 +91,7 @@ OUString XmlTestTools::getXPath(xmlDocPtr pXmlDoc, const OString& rXPath, const
     }
     xmlNodePtr pXmlNode = pXmlNodes->nodeTab[0];
     xmlChar * prop = xmlGetProp(pXmlNode, BAD_CAST(rAttribute.getStr()));
-    OString sAttAbsent = "In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath
+    OString sAttAbsent = OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath
                          + "' no attribute '" + rAttribute + "' exist";
     CPPUNIT_ASSERT_MESSAGE(sAttAbsent.getStr(), prop);
     OUString s(convert(prop));
@@ -112,7 +112,7 @@ OUString XmlTestTools::getXPathContent(xmlDocPtr pXmlDoc, const OString& rXPath)
             xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
 
             CPPUNIT_ASSERT_MESSAGE(
-                OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' not found")
+                OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' not found")
                     .getStr(),
                 xmlXPathNodeSetGetLength(pXmlNodes) > 0);
 
@@ -164,7 +164,7 @@ void XmlTestTools::assertXPath(xmlDocPtr pXmlDoc, const OString& rXPath)
 void XmlTestTools::assertXPath(xmlDocPtr pXmlDoc, const OString& rXPath, const OString& rAttribute, const OUString& rExpectedValue)
 {
     OUString aValue = getXPath(pXmlDoc, rXPath, rAttribute);
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, attribute '" + rAttribute + "' of '" + rXPath + "' incorrect value.").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, attribute '" + rAttribute + "' of '" + rXPath + "' incorrect value.").getStr(),
                                  rExpectedValue, aValue);
 }
 
@@ -181,14 +181,14 @@ void XmlTestTools::assertXPath(xmlDocPtr pXmlDoc, const OString& rXPath, int nNu
 {
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
                                  nNumberOfNodes, xmlXPathNodeSetGetLength(pXmlNodes));
     xmlXPathFreeObject(pXmlObj);
 }
 
 void XmlTestTools::assertXPathContent(xmlDocPtr pXmlDoc, const OString& rXPath, const OUString& rContent)
 {
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath contents of child does not match").getStr(), rContent, getXPathContent(pXmlDoc, rXPath));
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath contents of child does not match").getStr(), rContent, getXPathContent(pXmlDoc, rXPath));
 }
 
 void XmlTestTools::assertXPathNSDef(xmlDocPtr pXmlDoc, const OString& rXPath,
@@ -197,7 +197,7 @@ void XmlTestTools::assertXPathNSDef(xmlDocPtr pXmlDoc, const OString& rXPath,
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
     CPPUNIT_ASSERT_MESSAGE(
-        OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' not found").getStr(),
+        OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' not found").getStr(),
         xmlXPathNodeSetGetLength(pXmlNodes) > 0);
 
     xmlNodePtr pXmlNode = pXmlNodes->nodeTab[0];
@@ -223,10 +223,10 @@ void XmlTestTools::assertXPathChildren(xmlDocPtr pXmlDoc, const OString& rXPath,
 #if LIBXML_VERSION >= 20703 /* xmlChildElementCount is only available in libxml2 >= 2.7.3 */
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
                                  1, xmlXPathNodeSetGetLength(pXmlNodes));
     xmlNodePtr pXmlNode = pXmlNodes->nodeTab[0];
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of child-nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of child-nodes is incorrect").getStr(),
                                  nNumberOfChildNodes, static_cast<int>(xmlChildElementCount(pXmlNode)));
     xmlXPathFreeObject(pXmlObj);
 #else
@@ -240,10 +240,10 @@ void XmlTestTools::assertXPathNoAttribute(xmlDocPtr pXmlDoc, const OString& rXPa
 {
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
                                  1, xmlXPathNodeSetGetLength(pXmlNodes));
     xmlNodePtr pXmlNode = pXmlNodes->nodeTab[0];
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' unexpected '" + rAttribute + "' attribute").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' unexpected '" + rAttribute + "' attribute").getStr(),
                                  static_cast<xmlChar*>(nullptr), xmlGetProp(pXmlNode, BAD_CAST(rAttribute.getStr())));
     xmlXPathFreeObject(pXmlObj);
 }
@@ -252,7 +252,7 @@ int XmlTestTools::getXPathPosition(xmlDocPtr pXmlDoc, const OString& rXPath, con
 {
     xmlXPathObjectPtr pXmlObj = getXPathNode(pXmlDoc, rXPath);
     xmlNodeSetPtr pXmlNodes = pXmlObj->nodesetval;
-    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
+    CPPUNIT_ASSERT_EQUAL_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath + "' number of nodes is incorrect").getStr(),
                                  1,
                                  xmlXPathNodeSetGetLength(pXmlNodes));
     xmlNodePtr pXmlNode = pXmlNodes->nodeTab[0];
@@ -268,7 +268,7 @@ int XmlTestTools::getXPathPosition(xmlDocPtr pXmlDoc, const OString& rXPath, con
         ++nRet;
     }
     xmlXPathFreeObject(pXmlObj);
-    CPPUNIT_ASSERT_MESSAGE(OString("In <" + OString(pXmlDoc->name) + ">, XPath '" + rXPath
+    CPPUNIT_ASSERT_MESSAGE(OString(OStringLiteral("In <") + pXmlDoc->name + ">, XPath '" + rXPath
                                    + "' child '" + rChildName + "' not found")
                                .getStr(),
         bFound);