ADD: fspSearchable to TFileSourceProperties, and appy in TMainCommands.cm_Search()

src/filesources/filesystem/ufilesystemfilesource.pas

@@ -823,7 +823,7 @@ end;
 function TFileSystemFileSource.GetProperties: TFileSourceProperties;
 begin
   Result := [
-    fspDirectAccess, fspListFlatView, fspNoneParent
+    fspDirectAccess, fspListFlatView, fspNoneParent, fspSearchable
 {$IFDEF UNIX}
   , fspCaseSensitive
 {$ENDIF}

src/filesources/searchresult/usearchresultfilesource.pas

@@ -112,6 +112,7 @@ function TSearchResultFileSource.GetProperties: TFileSourceProperties;
 begin
   Result := inherited GetProperties - [fspNoneParent, fspListFlatView];
   if (fspDirectAccess in Result) then Result+= [fspLinksToLocalFiles];
+  Include(Result, fspSearchable);
 end;
 
 function TSearchResultFileSource.SetCurrentWorkingDirectory(NewDir: String): Boolean;

src/filesources/ufilesourceproperty.pas

@@ -77,7 +77,11 @@ type
     {en
        Set, if the file source supports custom file icons.
     }
-    fspCustomIcon
+    fspCustomIcon,
+    {en
+       Set, if the file source supports searching in FindDlg.
+    }
+    fspSearchable
   );
 
   TFileSourceProperties = set of TFileSourceProperty;

src/filesources/wcxarchive/uwcxarchivefilesource.pas

@@ -511,7 +511,7 @@ end;
 
 function TWcxArchiveFileSource.GetProperties: TFileSourceProperties;
 begin
-  Result := [fspUsesConnections, fspListFlatView];
+  Result := [fspUsesConnections, fspListFlatView, fspSearchable];
 end;
 
 function TWcxArchiveFileSource.GetSupportedFileProperties: TFilePropertiesTypes;

src/umaincommands.pas

@@ -3545,19 +3545,17 @@ procedure TMainCommands.cm_Search(const Params: array of string);
 var
   TemplateName: String;
 begin
-  if not (frmMain.ActiveFrame.FileSource.IsClass(TFileSystemFileSource) or
-    frmMain.ActiveFrame.FileSource.IsClass(TWcxArchiveFileSource) or
-    frmMain.ActiveFrame.FileSource.IsClass(TSearchResultFileSource) ) then
+  if fspSearchable in frmMain.ActiveFrame.FileSource.GetProperties then
   begin
-    msgError(rsMsgErrNotSupported)
-  end
-  else begin
     if Length(Params) > 0 then
       TemplateName:= Params[0]
     else begin
       TemplateName:= gSearchDefaultTemplate;
     end;
     ShowFindDlg(frmMain.ActiveFrame, TemplateName);
+  end
+  else begin
+    msgError(rsMsgErrNotSupported)
   end;
 end;