Output position info for various error return codes - close #10

spec/test_error_positions.d

@@ -0,0 +1,36 @@
+import testparser;
+import std.stdio;
+
+int main()
+{
+    return 0;
+}
+
+unittest
+{
+    string input = "a 42";
+    p_context_t context;
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+
+    input = "a\n123\na  a";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_UNEXPECTED_TOKEN);
+    assert(p_position(&context) == p_position_t(2, 3));
+
+    input = "12";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_UNEXPECTED_TOKEN);
+    assert(p_position(&context) == p_position_t(0, 0));
+
+    input = "a 12\n\nab";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_UNEXPECTED_INPUT);
+    assert(p_position(&context) == p_position_t(2, 1));
+
+    input = "a 12\n\na\n\n77\na   \xAA";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_DECODE_ERROR);
+    writeln(p_position(&context));
+    assert(p_position(&context) == p_position_t(5, 4));
+}