Added default diagram generation error for empty diagrams (#246)

src/config/config.cc

@@ -237,6 +237,7 @@ void inheritable_diagram_options::inherit(
         parent.generate_condition_statements);
     debug_mode.override(parent.debug_mode);
     generate_metadata.override(parent.generate_metadata);
+    allow_empty_diagrams.override(parent.allow_empty_diagrams);
     type_aliases.override(parent.type_aliases);
 }
 

src/config/config.h

@@ -577,6 +577,7 @@ struct inheritable_diagram_options {
         "message_comment_width", clanguml::util::kDefaultMessageCommentWidth};
     option<bool> debug_mode{"debug_mode", false};
     option<bool> generate_metadata{"generate_metadata", true};
+    option<bool> allow_empty_diagrams{"allow_empty_diagrams", false};
 
 protected:
     // This is the relative path with respect to the `base_directory`,

src/config/schema.h

@@ -306,6 +306,7 @@ root:
     query_driver: !optional string
     add_compile_flags: !optional [string]
     remove_compile_flags: !optional [string]
+    allow_empty_diagrams: !optional bool
     diagram_templates: !optional diagram_templates_t
     diagrams: !required map_t<string;diagram_t>
     #

src/config/yaml_decoders.cc

@@ -820,6 +820,7 @@ template <> struct convert<config> {
         get_option(node, rhs.using_module);
         get_option(node, rhs.output_directory);
         get_option(node, rhs.query_driver);
+        get_option(node, rhs.allow_empty_diagrams);
         get_option(node, rhs.compilation_database_dir);
         get_option(node, rhs.add_compile_flags);
         get_option(node, rhs.remove_compile_flags);