Load libraries case insensitive on case sensitive OS

Libraries where files are stored in the unexpected files will still give
warnings, but OpenModelica will load them regardless.

Belonging to [master]:
  - OpenModelica/OMCompiler#3064

Compiler/FrontEnd/ClassLoader.mo

@@ -403,8 +403,12 @@ algorithm
   end if;
   (cl as Absyn.CLASS(name=cname,body=body,info=info))::{} := cs;
   if not stringEqual(cname,pack) then
-    Error.addSourceMessage(Error.LIBRARY_UNEXPECTED_NAME, {pack,cname}, info);
-    fail();
+    if stringEqual(System.tolower(cname), System.tolower(pack)) then
+      Error.addSourceMessage(Error.LIBRARY_UNEXPECTED_NAME_CASE_SENSITIVE, {pack,cname}, info);
+    else
+      Error.addSourceMessage(Error.LIBRARY_UNEXPECTED_NAME, {pack,cname}, info);
+      fail();
+    end if;
   end if;
   s1 := Absyn.withinString(w1);
   s2 := Absyn.withinString(w2);
@@ -437,7 +441,7 @@ algorithm
   (po) := matchcontinue (cl,filename,mp,numError)
     local
       String contents, duplicatesStr, differencesStr, classFilename;
-      list<String> duplicates, namesToFind, mofiles, subdirs, differences, intersection;
+      list<String> duplicates, namesToFind, mofiles, subdirs, differences, intersection, caseInsensitiveFiles;
       list<Absyn.ClassPart> cp;
       SourceInfo info;
       list<PackageOrder> po1, po2;
@@ -469,11 +473,12 @@ algorithm
           mofiles = listAppend(subdirs,mofiles);
           // check if all are present in the package.order
           differences = List.setDifference(mofiles, namesToFind);
+          (po1) = getPackageContentNamesinParts(namesToFind,cp,{});
+          (po1,differences) = List.map3Fold(po1,checkPackageOrderFilesExist,mp,info,encrypted,differences);
+
           // issue a warning if not all are present
           differencesStr = stringDelimitList(differences, "\n\t");
           Error.assertionOrAddSourceMessage(listEmpty(differences),Error.PACKAGE_ORDER_FILE_NOT_COMPLETE,{differencesStr},SOURCEINFO(filename,true,0,0,0,0,0.0));
-          po1 = getPackageContentNamesinParts(namesToFind,cp,{});
-          List.map3_0(po1,checkPackageOrderFilesExist,mp,info,encrypted);
 
           po2 = List.map(differences, makeClassLoad);
 
@@ -525,18 +530,32 @@ algorithm
 end makeClassLoad;
 
 protected function checkPackageOrderFilesExist
-  input PackageOrder po;
+  input output PackageOrder po;
   input String mp;
   input SourceInfo info;
   input Boolean encrypted = false;
+  input output list<String> differences;
 algorithm
   _ := match (po,mp,info)
     local
-      String pd,str;
+      String pd,str,str2,str3,str4;
+      list<String> strs;
     case (CLASSLOAD(str),_,_)
-      equation
-        pd = Autoconf.pathDelimiter;
-        Error.assertionOrAddSourceMessage(System.directoryExists(mp + pd + str) or System.regularFileExists(mp + pd + str + (if encrypted then ".moc" else ".mo")),Error.PACKAGE_ORDER_FILE_NOT_FOUND,{str},info);
+      algorithm
+        pd := Autoconf.pathDelimiter;
+        str2 := str + (if encrypted then ".moc" else ".mo");
+        if not (System.directoryExists(mp + pd + str) or System.regularFileExists(mp + pd + str2)) then
+          try
+            str3 := List.find(System.moFiles(mp), function Util.stringEqCaseInsensitive(str2=System.tolower(str2)));
+          else
+            Error.addSourceMessage(Error.PACKAGE_ORDER_FILE_NOT_FOUND,{str},info);
+            fail();
+          end try;
+          Error.addSourceMessage(Error.PACKAGE_ORDER_CASE_SENSITIVE, {str, str2, str3}, info);
+          str4 := Util.removeLastNChar(str3,if encrypted then 4 else 3);
+          differences := List.removeOnTrue(str4, stringEq, differences);
+          po := CLASSLOAD(str4);
+        end if;
       then ();
     else ();
   end match;

Compiler/Util/Error.mo

@@ -598,7 +598,7 @@ public constant Message LIBRARY_ONE_PACKAGE_PER_FILE = MESSAGE(234, GRAMMAR(), E
   Util.gettext("Modelica library files should contain exactly one package, but found the following classes: %s."));
 public constant Message LIBRARY_UNEXPECTED_WITHIN = MESSAGE(235, GRAMMAR(), ERROR(),
   Util.gettext("Expected the package to have %s but got %s."));
-public constant Message LIBRARY_UNEXPECTED_NAME = MESSAGE(236, GRAMMAR(), ERROR(),
+public constant Message LIBRARY_UNEXPECTED_NAME = MESSAGE(236, SCRIPTING(), ERROR(),
   Util.gettext("Expected the package to have name %s, but got %s."));
 public constant Message PACKAGE_MO_NOT_IN_ORDER = MESSAGE(237, GRAMMAR(), ERROR(),
   Util.gettext("Elements in the package.mo-file need to be in the same relative order as the package.order file. Got element named %s but it was already added because it was not the next element in the list at that time."));
@@ -829,8 +829,12 @@ public constant Message WHEN_IF_VARIABLE_MISMATCH = MESSAGE(350, TRANSLATION(),
   Util.gettext("The branches of an if-equation inside a when-equation must have the same set of component references on the left-hand side."));
 public constant Message DIMENSION_DEDUCTION_FROM_BINDING_FAILURE = MESSAGE(351, TRANSLATION(), ERROR(),
   Util.gettext("Dimension %s of ‘%s‘ could not be deduced from the component's binding equation ‘%s‘."));
-public constant Message NON_REAL_FLOW_OR_STREAM = MESSAGE(351, TRANSLATION(), ERROR(),
+public constant Message NON_REAL_FLOW_OR_STREAM = MESSAGE(352, TRANSLATION(), ERROR(),
   Util.gettext("Invalid prefix ‘%s‘ on non-Real component ‘%s‘."));
+public constant Message LIBRARY_UNEXPECTED_NAME_CASE_SENSITIVE = MESSAGE(353, SCRIPTING(), WARNING(),
+  Util.gettext("Expected the package to have name %s, but got %s. Proceeding since only the case of the names are different."));
+public constant Message PACKAGE_ORDER_CASE_SENSITIVE = MESSAGE(354, SCRIPTING(), WARNING(),
+  Util.gettext("The package.order file contains a class %s, which is expected to be stored in file %s, but seems to be named %s. Proceeding since only the case of the names are different."));
 public constant Message INITIALIZATION_NOT_FULLY_SPECIFIED = MESSAGE(496, TRANSLATION(), WARNING(),
   Util.gettext("The initial conditions are not fully specified. %s."));
 public constant Message INITIALIZATION_OVER_SPECIFIED = MESSAGE(497, TRANSLATION(), WARNING(),

Compiler/Util/Util.mo

@@ -1403,6 +1403,13 @@ algorithm
   end match;
 end stringBool2;
 
+public function stringEqCaseInsensitive
+  input String str1, str2;
+  output Boolean eq;
+algorithm
+  eq := stringEq(System.tolower(str1), System.tolower(str2));
+end stringEqCaseInsensitive;
+
 public function optionList<T>
   "SOME(a) => {a}
    NONE()  => {}"
@@ -1566,6 +1573,14 @@ algorithm
   outStr := substring(str,1,stringLength(str)-4);
 end removeLast4Char;
 
+public function removeLastNChar
+  input String str;
+  input Integer n;
+  output String outStr;
+algorithm
+  outStr := substring(str,1,stringLength(str)-n);
+end removeLastNChar;
+
 public function stringNotEqual
   input String str1;
   input String str2;