Improve tests.h just a little

.drone.yml

@@ -2,7 +2,6 @@
 kind: pipeline
 type: docker
 name: default
-
 steps:
   - name: hello world
     image: alpine:3.16.2
@@ -13,12 +12,17 @@ steps:
     image: python:3.11-rc-alpine
     commands:
       - python3 -c "print(6 * 7)"
+---
+kind: pipeline
+type: docker
+name: algo2
+steps:
   - name: pairingheap
     image: gcc:12.2.0
     commands:
       - cd algo2/pairingheap
-      - gcc -Wall -Werror -o main pairingheap.c
-      - ./main
+      - gcc -Wall -Werror -o tests pairingheap.c
+      - ./tests
   - name: radixheap
     image: gcc:12.2.0
     commands:

README.md

@@ -2,4 +2,4 @@
 
 # CI Playground
 
-This is where is play around with [Drone](https://ci.pbrinkmeier.de).
+This is where I play around with [Drone](https://ci.pbrinkmeier.de).

algo2/pairingheap/pairingheap.c

@@ -2,6 +2,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "tests.h"
+
 struct PHeapNode {
     int key;
     struct PHeapNode *parent;
@@ -160,23 +162,64 @@ struct PHeapNode *ph_deletemin(struct PHeap *ph) {
     return m;
 }
 
+void ph_deinit_free(struct PHeap *ph) {
+    while (ph->min != NULL) {
+        struct PHeapNode *h = ph_deletemin(ph);
+        free(h);
+    }
+}
+
+int cmp_int(const void *a, const void *b) {
+    return *((int *) a) - *((int *) b);
+}
+
 int main() {
+    TEST("consecutive deleteMin calls yield increasing results", {
         srand(2309);
     
         struct PHeap ph;
         ph_init(&ph);
 
-    for (int i = 0; i < 15; i++) {
-        ph_insert_malloc(&ph, rand() % 100);
+        for (int i = 0; i < 1000; i++) {
+            ph_insert_malloc(&ph, rand());
         }
 
-    ph_print(&ph);
-
+        int max = INT_MIN;
         while (ph.min != NULL) {
             struct PHeapNode *h = ph_deletemin(&ph);
-        printf("deleteMin: %d\n", h->key);
+            ASSERT(h->key >= max);
+            max = h->key;
             free(h);
         }
 
-    ph_print(&ph);
+        ph_deinit_free(&ph);
+    })
+
+    TEST("deleteMin yields the same order as qsort", {
+        srand(2309);
+
+        struct PHeap ph;
+        ph_init(&ph);
+
+        int n = 1000;
+        int xs[n];
+
+        for (int i = 0; i < n; i++) {
+            xs[i] = rand();
+            ph_insert_malloc(&ph, xs[i]);
+        }
+
+        qsort(xs, n, sizeof(int), cmp_int);
+
+        for (int i = 0; i < n; i++) {
+            struct PHeapNode *h = ph_deletemin(&ph);
+            ASSERT(h->key == xs[i]);
+            free(h);
+        }
+        ASSERT(ph.min == NULL);
+
+        ph_deinit_free(&ph);
+    })
+
+    DONE
 }

algo2/pairingheap/tests.h

@@ -0,0 +1,62 @@
+// single-header unit test framework.
+// if you want to keep your sanity, do not use this.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+
+// globals.
+struct tests_state {
+  int passed_tests;
+  int run_tests;
+  int total_tests;
+  char *current_label;
+};
+
+struct tests_state tests_state = { 0, 0, 0, NULL };
+
+/* Basic idea:
+
+TEST("...", {
+    ASSERT(...)
+    ASSERT(...)
+    ...
+})
+
+
+TEST("...", {
+    ASSERT(...)
+    ASSERT(...)
+    ...
+})
+
+DONE
+
+*/
+
+#define TEST(LABEL, BLOCK) \
+tests_state.current_label = LABEL; \
+tests_state.run_tests++; \
+tests_state.total_tests = __COUNTER__; \
+BLOCK; \
+fprintf(stderr, "[%3d] \x1b[32m%s ✓\x1b[0m\n", tests_state.run_tests, tests_state.current_label); \
+tests_state.passed_tests++;
+
+#define ASSERT(EXPR) \
+if (!(EXPR)) { \
+  fprintf(stderr, "[%3d] \x1b[31m%s ❌\x1b[0m\n", tests_state.run_tests, tests_state.current_label); \
+  fprintf(stderr, "       Assertion failed in %s:%d:\n", __FILE__, __LINE__); \
+  fprintf(stderr, "       " #EXPR "\n"); \
+  goto tests_bail; \
+}
+
+#define DONE \
+tests_bail: { \
+  tests_state.total_tests = __COUNTER__; \
+  fprintf(stderr, "[\x1b[%dm***\x1b[0m] %d/%d tests passed", tests_state.passed_tests == tests_state.total_tests ? 32 : 31, tests_state.passed_tests, tests_state.total_tests); \
+  if (tests_state.total_tests > tests_state.run_tests) { \
+    fprintf(stderr, ", %d skipped", tests_state.total_tests - tests_state.run_tests); \
+  } \
+  fprintf(stderr, ".\n"); \
+  if (tests_state.passed_tests != tests_state.total_tests) exit(1); \
+}