properly format multiline error messages

apt-pkg/contrib/error.h

@@ -316,15 +316,30 @@ private:								/*{{{*/
 		Item(char const *Text, MsgType const &Type) :
 			Text(Text), Type(Type) {};
 
-		friend std::ostream& operator<< (std::ostream &out, Item i) {
+		APT_HIDDEN friend std::ostream& operator<< (std::ostream &out, Item i) {
 			switch(i.Type) {
 			case FATAL:
-			case ERROR: out << "E"; break;
-			case WARNING: out << "W"; break;
-			case NOTICE: out << "N"; break;
-			case DEBUG: out << "D"; break;
+			case ERROR: out << 'E'; break;
+			case WARNING: out << 'W'; break;
+			case NOTICE: out << 'N'; break;
+			case DEBUG: out << 'D'; break;
 			}
-			return out << ": " << i.Text;
+			out << ": ";
+			std::string::size_type line_start = 0;
+			std::string::size_type line_end;
+			while ((line_end = i.Text.find_first_of("\n\r", line_start)) != std::string::npos) {
+				if (line_start != 0)
+				   out << std::endl << "   ";
+				out << i.Text.substr(line_start, line_end - line_start);
+				line_start = i.Text.find_first_not_of("\n\r", line_end + 1);
+				if (line_start == std::string::npos)
+				   break;
+			}
+			if (line_start == 0)
+			   out << i.Text;
+			else if (line_start != std::string::npos)
+			   out << std::endl << "   " << i.Text.substr(line_start);
+			return out;
 		}
 	};
 

test/libapt/globalerror_test.cc

@@ -116,6 +116,16 @@ TEST(GlobalErrorTest,LongMessage)
    EXPECT_FALSE(e.Errno("errno", "%s horrible %s %d times", longText.c_str(), "happened", 2));
    EXPECT_TRUE(e.PopMessage(text));
    EXPECT_EQ(std::string(longText).append(" horrible happened 2 times - errno (0: ").append(textOfErrnoZero).append(")"), text);
+
+   EXPECT_FALSE(e.Error("%s horrible %s %d times", longText.c_str(), "happened", 2));
+   std::ostringstream out;
+   e.DumpErrors(out);
+   EXPECT_EQ(std::string("E: ").append(longText).append(" horrible happened 2 times\n"), out.str());
+
+   EXPECT_FALSE(e.Errno("errno", "%s horrible %s %d times", longText.c_str(), "happened", 2));
+   std::ostringstream out2;
+   e.DumpErrors(out2);
+   EXPECT_EQ(std::string("E: ").append(longText).append(" horrible happened 2 times - errno (0: ").append(textOfErrnoZero).append(")\n"), out2.str());
 }
 TEST(GlobalErrorTest,UTF8Message)
 {
@@ -126,6 +136,11 @@ TEST(GlobalErrorTest,UTF8Message)
    EXPECT_FALSE(e.PopMessage(text));
    EXPECT_EQ("Репозиторий не обновлён и будут 4 test", text);
 
+   EXPECT_FALSE(e.Warning("Репозиторий не обновлён и будут %d %s", 4, "test"));
+   std::ostringstream out;
+   e.DumpErrors(out);
+   EXPECT_EQ("W: Репозиторий не обновлён и будут 4 test\n", out.str());
+
    std::string longText;
    for (size_t i = 0; i < 50; ++i)
       longText.append("РезийбёбAZ");
@@ -133,3 +148,22 @@ TEST(GlobalErrorTest,UTF8Message)
    EXPECT_FALSE(e.PopMessage(text));
    EXPECT_EQ(longText, text);
 }
+TEST(GlobalErrorTest,MultiLineMessage)
+{
+   GlobalError e;
+   std::string text;
+
+   EXPECT_FALSE(e.Warning("Sometimes one line isn't enough.\nYou do know what I mean, right?\r\n%s?\rGood because I don't.", "Right"));
+   EXPECT_FALSE(e.PopMessage(text));
+   EXPECT_EQ("Sometimes one line isn't enough.\nYou do know what I mean, right?\r\nRight?\rGood because I don't.", text);
+
+   EXPECT_FALSE(e.Warning("Sometimes one line isn't enough.\nYou do know what I mean, right?\r\n%s?\rGood because I don't.", "Right"));
+   std::ostringstream out;
+   e.DumpErrors(out);
+   EXPECT_EQ("W: Sometimes one line isn't enough.\n   You do know what I mean, right?\n   Right?\n   Good because I don't.\n", out.str());
+
+   EXPECT_FALSE(e.Warning("Sometimes one line isn't enough.\nYou do know what I mean, right?\r\n%s?\rGood because I don't.\n", "Right"));
+   std::ostringstream out2;
+   e.DumpErrors(out2);
+   EXPECT_EQ("W: Sometimes one line isn't enough.\n   You do know what I mean, right?\n   Right?\n   Good because I don't.\n", out2.str());
+}