Added String::dedent() to remove text indentation

This functions similarly to Python's textwrap.dedent()

It's also been applied to doc_data.cpp to remove extra whitespace while
parsing the XML.

core/ustring.cpp

@@ -2757,6 +2757,48 @@ CharType String::ord_at(int p_idx) const {
 	return operator[](p_idx);
 }
 
+String String::dedent() const {
+
+	String new_string;
+	String indent;
+	bool has_indent = false;
+	bool has_text = false;
+	int line_start = 0;
+	int indent_stop = -1;
+
+	for (int i = 0; i < length(); i++) {
+
+		CharType c = operator[](i);
+		if (c == '\n') {
+			if (has_text)
+				new_string += substr(indent_stop, i - indent_stop);
+			new_string += "\n";
+			has_text = false;
+			line_start = i + 1;
+			indent_stop = -1;
+		} else if (!has_text) {
+			if (c > 32) {
+				has_text = true;
+				if (!has_indent) {
+					has_indent = true;
+					indent = substr(line_start, i - line_start);
+					indent_stop = i;
+				}
+			}
+			if (has_indent && indent_stop < 0) {
+				int j = i - line_start;
+				if (j >= indent.length() || c != indent[j])
+					indent_stop = i;
+			}
+		}
+	}
+
+	if (has_text)
+		new_string += substr(indent_stop, length() - indent_stop);
+
+	return new_string;
+}
+
 String String::strip_edges(bool left, bool right) const {
 
 	int len = length();

core/ustring.h

@@ -176,6 +176,7 @@ public:
 
 	String left(int p_pos) const;
 	String right(int p_pos) const;
+	String dedent() const;
 	String strip_edges(bool left = true, bool right = true) const;
 	String strip_escapes() const;
 	String get_extension() const;

core/variant_call.cpp

@@ -260,6 +260,7 @@ struct _VariantCall {
 	VCALL_LOCALMEM0R(String, to_lower);
 	VCALL_LOCALMEM1R(String, left);
 	VCALL_LOCALMEM1R(String, right);
+	VCALL_LOCALMEM0R(String, dedent);
 	VCALL_LOCALMEM2R(String, strip_edges);
 	VCALL_LOCALMEM0R(String, get_extension);
 	VCALL_LOCALMEM0R(String, get_basename);
@@ -1457,6 +1458,7 @@ void register_variant_methods() {
 	ADDFUNC0R(STRING, STRING, String, get_basename, varray());
 	ADDFUNC1R(STRING, STRING, String, plus_file, STRING, "file", varray());
 	ADDFUNC1R(STRING, INT, String, ord_at, INT, "at", varray());
+	ADDFUNC0(STRING, STRING, String, dedent, varray());
 	ADDFUNC2(STRING, NIL, String, erase, INT, "position", INT, "chars", varray());
 	ADDFUNC0R(STRING, INT, String, hash, varray());
 	ADDFUNC0R(STRING, STRING, String, md5_text, varray());

editor/doc/doc_data.cpp

@@ -615,6 +615,11 @@ void DocData::generate(bool p_basic_types) {
 	}
 }
 
+static String _format_description(const String &string) {
+
+	return string.dedent().strip_edges().replace("\n", "\n\n");
+}
+
 static Error _parse_methods(Ref<XMLParser> &parser, Vector<DocData::MethodDoc> &methods) {
 
 	String section = parser->get_node_name();
@@ -661,7 +666,7 @@ static Error _parse_methods(Ref<XMLParser> &parser, Vector<DocData::MethodDoc> &
 
 							parser->read();
 							if (parser->get_node_type() == XMLParser::NODE_TEXT)
-								method.description = parser->get_node_data().strip_edges();
+								method.description = _format_description(parser->get_node_data());
 						}
 
 					} else if (parser->get_node_type() == XMLParser::NODE_ELEMENT_END && parser->get_node_name() == element)
@@ -776,12 +781,12 @@ Error DocData::_load(Ref<XMLParser> parser) {
 
 					parser->read();
 					if (parser->get_node_type() == XMLParser::NODE_TEXT)
-						c.brief_description = parser->get_node_data().strip_edges();
+						c.brief_description = _format_description(parser->get_node_data());
 
 				} else if (name == "description") {
 					parser->read();
 					if (parser->get_node_type() == XMLParser::NODE_TEXT)
-						c.description = parser->get_node_data().strip_edges();
+						c.description = _format_description(parser->get_node_data());
 				} else if (name == "tutorials") {
 					parser->read();
 					if (parser->get_node_type() == XMLParser::NODE_TEXT)
@@ -823,7 +828,7 @@ Error DocData::_load(Ref<XMLParser> parser) {
 									prop.enumeration = parser->get_attribute_value("enum");
 								parser->read();
 								if (parser->get_node_type() == XMLParser::NODE_TEXT)
-									prop.description = parser->get_node_data().strip_edges();
+									prop.description = _format_description(parser->get_node_data());
 								c.properties.push_back(prop);
 							} else {
 								ERR_EXPLAIN("Invalid tag in doc file: " + name);