Also handle OUString with non-RTL_TEXTENCODING_ASCII_US encoding

(just in case)

Change-Id: I7ba2967c1cef81a3f6604077d876c8b993f7f16a
Reviewed-on: https://gerrit.libreoffice.org/42609Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

compilerplugins/clang/stringconstant.cxx

@@ -756,6 +756,8 @@ bool StringConstant::VisitCXXConstructExpr(CXXConstructExpr const * expr) {
         ChangeKind kind;
         PassThrough pass;
         bool simplify;
+        bool encIsAscii;
+        std::string enc;
         switch (expr->getConstructor()->getNumParams()) {
         case 1:
             if (!loplugin::TypeCheck(
@@ -846,11 +848,12 @@ bool StringConstant::VisitCXXConstructExpr(CXXConstructExpr const * expr) {
                     return true;
                 }
                 if (!expr->getArg(2)->EvaluateAsInt(
-                        res, compiler.getASTContext())
-                    || res != 11) // RTL_TEXTENCODING_ASCII_US
+                        res, compiler.getASTContext()))
                 {
                     return true;
                 }
+                encIsAscii = res == 11; // RTL_TEXTENCODING_ASCII_US
+                enc = res.toString(10);
                 if (!expr->getArg(3)->EvaluateAsInt(
                         res, compiler.getASTContext())
                     || res != 0x333) // OSTRING_TO_OUSTRING_CVTFLAGS
@@ -1056,9 +1059,10 @@ bool StringConstant::VisitCXXConstructExpr(CXXConstructExpr const * expr) {
         if (simplify) {
             report(
                 DiagnosticsEngine::Warning,
-                "simplify construction of %0 with %1",
+                ("simplify construction of %0 with %1%select{ (but beware, the"
+                 " given textencoding %3 is not RTL_TEXTENCODING_ASCII_US)|}2"),
                 expr->getExprLoc())
-                << classdecl << describeChangeKind(kind)
+                << classdecl << describeChangeKind(kind) << encIsAscii << enc
                 << expr->getSourceRange();
         }
         return true;

compilerplugins/clang/test/stringconstant.cxx

@@ -60,6 +60,10 @@ int main() {
     (void)aFoo;
     Foo aFoo2(OUString("xxx")); // expected-error {{in call of 'Foo::Foo', replace 'OUString' constructed from a string literal directly with the string literal}}
     (void)aFoo2;
+
+    (void) OUString("xxx", 3, RTL_TEXTENCODING_ASCII_US); // expected-error {{simplify construction of 'OUString' with string constant argument [loplugin:stringconstant]}}
+    (void) OUString("xxx", 3, RTL_TEXTENCODING_ISO_8859_1); // expected-error {{simplify construction of 'OUString' with string constant argument (but beware, the given textencoding 12 is not RTL_TEXTENCODING_ASCII_US) [loplugin:stringconstant]}}
+    (void) OUString("x\xA0x", 3, RTL_TEXTENCODING_ISO_8859_1);
 }