https://github.com/akkartik/mu/blob/master/002test.cc
  1 //: A simple test harness. To create new tests, define functions starting with
  2 //: 'test_'. To run all tests so defined, run:
  3 //:   $ ./mu test
  4 //:
  5 //: Every layer should include tests, and can reach into previous layers.
  6 //: However, it seems like a good idea never to reach into tests from previous
  7 //: layers. Every test should be a contract that always passes as originally
  8 //: written, regardless of any later layers. Avoid writing 'temporary' tests
  9 //: that are only meant to work until some layer.
 10 
 11 :(before "End Types")
 12 typedef void (*test_fn)(void);
 13 :(before "Globals")
 14 // move a global ahead into types that we can't generate an extern declaration for
 15 const test_fn Tests[] = {
 16   #include "test_list"  // auto-generated; see 'build*' scripts
 17 };
 18 
 19 :(before "End Globals")
 20 bool Run_tests = false;
 21 bool Passed = true;  // set this to false inside any test to indicate failure
 22 
 23 :(before "End Includes")
 24 #define CHECK(X) \
 25   if (Passed && !(X)) { \
 26     cerr << "\nF - " << __FUNCTION__ << "(" << __FILE__ << ":" << __LINE__ << "): " << #X << '\n'; \
 27     Passed = false; \
 28     return;  /* Currently we stop at the very first failure. */ \
 29   }
 30 
 31 #define CHECK_EQ(X, Y) \
 32   if (Passed && (X) != (Y)) { \
 33     cerr << "\nF - " << __FUNCTION__ << "(" << __FILE__ << ":" << __LINE__ << "): " << #X << " == " << #Y << '\n'; \
 34     cerr << "  got " << (X) << '\n';  /* BEWARE: multiple eval */ \
 35     Passed = false; \
 36     return;  /* Currently we stop at the very first failure. */ \
 37   }
 38 
 39 :(before "End Reset")
 40 Passed = true;
 41 
 42 :(before "End Commandline Parsing")
 43 if (argc > 1 && is_equal(argv[1], "test")) {
 44   Run_tests = true;  --argc;  ++argv;  // shift 'test' out of commandline args
 45 }
 46 
 47 :(before "End Main")
 48 if (Run_tests) {
 49   // Test Runs
 50   // we run some tests and then exit; assume no state need be maintained afterward
 51 
 52   long num_failures = 0;
 53   // End Test Run Initialization
 54   time_t t;  time(&t);
 55   cerr << "C tests: " << ctime(&t);
 56   for (size_t i=0;  i < sizeof(Tests)/sizeof(Tests[0]);  ++i) {
 57 //?     cerr << "running " << Test_names[i] << '\n';
 58     run_test(i);
 59     if (Passed) cerr << '.';
 60     else ++num_failures;
 61   }
 62   cerr << '\n';
 63   // End Tests
 64   if (num_failures > 0) {
 65     cerr << num_failures << " failure"
 66          << (num_failures > 1 ? "s" : "")
 67          << '\n';
 68     return 1;
 69   }
 70   return 0;
 71 }
 72 
 73 :(after "End Main")
 74 //: Raise other unrecognized sub-commands as errors.
 75 //: We couldn't do this until now because we want `./subx test` to always
 76 //: succeed, no matter how many layers are included in the build.
 77 cerr << "nothing to do\n";
 78 return 1;
 79 
 80 :(code)
 81 void run_test(size_t i) {
 82   if (i >= sizeof(Tests)/sizeof(Tests[0])) {
 83     cerr << "no test " << i << '\n';
 84     return;
 85   }
 86   reset();
 87   // End Test Setup
 88   (*Tests[i])();
 89   // End Test Teardown
 90 }
 91 
 92 //: Convenience: run a single test
 93 :(before "Globals")
 94 // Names for each element of the 'Tests' global, respectively.
 95 const string Test_names[] = {
 96   #include "test_name_list"  // auto-generated; see 'build*' scripts
 97 };
 98 :(after "Test Runs")
 99 string maybe_single_test_to_run = argv[argc-1];
100 if (!starts_with(maybe_single_test_to_run, "test_"))
101   maybe_single_test_to_run.insert(0, "test_");
102 for (size_t i=0;  i < sizeof(Tests)/sizeof(Tests[0]);  ++i) {
103   if (Test_names[i] == maybe_single_test_to_run) {
104     run_test(i);
105     if (Passed) cerr << ".\n";
106     return 0;
107   }
108 }
109 
110 :(before "End Includes")
111 #include <stdlib.h>