VS: Fix nowarn compiler option to accept warning numbers.

Warning disables are transferred to the VS IDE `<NoWarn>` node.

Fixes: #18878

4 files changed, 18 insertions, 1 deletions

diff --git a/Source/cmGlobalVisualStudio10Generator.cxx b/Source/cmGlobalVisualStudio10Generator.cxx
index 07656ed..d8b2e89 100644
--- a/Source/cmGlobalVisualStudio10Generator.cxx
+++ b/Source/cmGlobalVisualStudio10Generator.cxx
@@ -1136,6 +1136,8 @@ static unsigned int cmLoadFlagTableSpecial(Json::Value entry,
           value |= cmIDEFlagTable::CaseInsensitive;
         } else if (s == "SpaceAppendable") {
           value |= cmIDEFlagTable::SpaceAppendable;
+        } else if (s == "CommaAppendable") {
+          value |= cmIDEFlagTable::CommaAppendable;
         }
       }
     }
diff --git a/Source/cmIDEFlagTable.h b/Source/cmIDEFlagTable.h
index 28d5d53..ff93432 100644
--- a/Source/cmIDEFlagTable.h
+++ b/Source/cmIDEFlagTable.h
@@ -29,6 +29,9 @@ struct cmIDEFlagTable
     SpaceAppendable = (1 << 7),     // a flag that if specified multiple times
                                     // should have its value appended to the
                                     // old value with spaces
+    CommaAppendable = (1 << 8),     // a flag that if specified multiple times
+                                    // should have its value appended to the
+                                    // old value with commas (e.g. C# /nowarn
 
     UserValueIgnored = UserValue | UserIgnored,
     UserValueRequired = UserValue | UserRequired
diff --git a/Source/cmIDEOptions.cxx b/Source/cmIDEOptions.cxx
index ee0c782..ea67d45 100644
--- a/Source/cmIDEOptions.cxx
+++ b/Source/cmIDEOptions.cxx
@@ -148,6 +148,8 @@ void cmIDEOptions::FlagMapUpdate(cmIDEFlagTable const* entry,
     this->FlagMap[entry->IDEName].push_back(new_value);
   } else if (entry->special & cmIDEFlagTable::SpaceAppendable) {
     this->FlagMap[entry->IDEName].append_with_space(new_value);
+  } else if (entry->special & cmIDEFlagTable::CommaAppendable) {
+    this->FlagMap[entry->IDEName].append_with_comma(new_value);
   } else {
     // Use the user-specified value.
     this->FlagMap[entry->IDEName] = new_value;
diff --git a/Source/cmIDEOptions.h b/Source/cmIDEOptions.h
index a4e5757..4a43073 100644
--- a/Source/cmIDEOptions.h
+++ b/Source/cmIDEOptions.h
@@ -65,12 +65,22 @@ protected:
       this->derived::operator=(r);
       return *this;
     }
+    FlagValue& append_with_comma(std::string const& r)
+    {
+      return append_with_separator(r, ',');
+    }
     FlagValue& append_with_space(std::string const& r)
     {
+      return append_with_separator(r, ' ');
+    }
+
+  private:
+    FlagValue& append_with_separator(std::string const& r, char separator)
+    {
       this->resize(1);
       std::string& l = this->operator[](0);
       if (!l.empty()) {
-        l += " ";
+        l += separator;
       }
       l += r;
       return *this;