Get test_lexer_unknown_character working for C

spec/propane_spec.rb

@@ -98,7 +98,25 @@ EOF
       end
 
       it "detects a lexer error when an unknown character is seen" do
-        write_grammar <<EOF
+        case language
+        when "c"
+          write_grammar <<EOF
+ptype int;
+token int /\\d+/ <<
+  int v = 0;
+  for (size_t i = 0u; i < match_length; i++)
+  {
+    v *= 10;
+    v += (match[i] - '0');
+  }
+  $$ = v;
+>>
+Start -> int <<
+  $$ = $1;
+>>
+EOF
+        when "d"
+          write_grammar <<EOF
 ptype int;
 token int /\\d+/ <<
   int v;
@@ -113,6 +131,7 @@ Start -> int <<
   $$ = $1;
 >>
 EOF
+        end
         build_parser(language: language)
         compile("spec/test_lexer_unknown_character.#{language}", language: language)
         results = run

spec/test_lexer_unknown_character.c

@@ -0,0 +1,18 @@
+#include "testparser.h"
+#include <assert.h>
+#include <string.h>
+
+int main()
+{
+    char const * input = "x";
+    p_context_t context;
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_UNEXPECTED_INPUT);
+
+    input = "123";
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    assert(p_result(&context) == 123u);
+
+    return 0;
+}