feat: added tests

1 files changed, 74 insertions, 32 deletions

diff --git a/src/stack-array.c b/src/stack-array.c
index 5f4ba41..a36de7b 100644
--- a/src/stack-array.c
+++ b/src/stack-array.c
@@ -1,3 +1,4 @@
+#include <assert.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -23,37 +24,53 @@ stack_init(struct stack *stack)
 }
 /* -->8-- */
 
-/* --8<-- stack2_push */
-bool
-stack_push(struct stack *stack, T data)
+/* --8<-- stack2_grow_if_needed */
+static bool
+stack_grow_if_needed(struct stack *stack)
 {
-        if ( stack->array == NULL ) {
-                if ( (stack->array = malloc(10 * sizeof *stack->array)) != NULL ) {
-                        stack->sz = 10;
-                        stack->p  = 0;
+        if ( stack->p == stack->sz ) {
+                if ( stack->array == NULL ) {
+                        static const size_t initial_size = 10;
+
+                        if ( (stack->array = reallocarray(NULL, initial_size, sizeof stack->array[0])) != NULL ) {
+                                stack->sz = initial_size;
+                                stack->p  = 0;
+                        }
+                        else {
+                                ERROR("out of memory");
+                                return false;
+                        }
                 }
                 else {
-                        ERROR("out of memory");
-                        return false;
+                        const size_t new_size = stack->sz * 3 / 2;
+
+                        T *new_array;
+
+                        if ( (new_array = reallocarray(stack->array, new_size, sizeof stack->array[0])) != NULL ) {
+                                stack->array = new_array;
+                                stack->sz    = new_size;
+                        }
+                        else {
+                                ERROR("out of memory");
+                                return false;
+                        }
                 }
         }
+        return true;
+}
+/* -->8-- */
 
-        if ( stack->p == stack->sz ) {
-                size_t new_sz;
-                T *    new_array;
+/* --8<-- stack2_push */
+bool
+stack_push(struct stack *stack, T data)
+{
+        bool success = stack_grow_if_needed(stack);
 
-                if ( (new_array = realloc(stack->array, (new_sz = (stack->sz * 3 / 2)) * sizeof *stack->array)) != NULL ) {
-                        stack->array = new_array;
-                        stack->sz    = new_sz;
-                }
-                else {
-                        ERROR("out of memory");
-                        return false;
-                }
+        if ( success ) {
+                stack->array[stack->p++] = data;
         }
 
-        stack->array[stack->p++] = data;
-        return true;
+        return success;
 }
 /* -->8-- */
 
@@ -90,26 +107,51 @@ stack_free(struct stack *stack)
 }
 /* -->8-- */
 
-int
-main()
+void
+test_stack(void)
 {
         struct stack stack[1];
 
         stack_init(stack);
 
-        for ( int i = 0; i != 20; ++i )
+        assert(stack_empty(stack) == true);
+
+        for ( int i = 0; i != 5; ++i )
                 stack_push(stack, i);
 
-        while ( !stack_empty(stack) ) {
-                int i;
+        assert(stack_empty(stack) == false);
 
-                if ( stack_pop(stack, &i) )
-                        printf("%d\n", i);
-                else
-                        ERROR("this shouldn't happen!");
-        }
+        T i;
+        assert(stack_pop(stack, &i) == true);
+        assert(i == 4);
+        assert(stack_pop(stack, &i) == true);
+        assert(i == 3);
+        assert(stack_pop(stack, &i) == true);
+        assert(i == 2);
+        assert(stack_pop(stack, &i) == true);
+        assert(i == 1);
+        assert(stack_pop(stack, &i) == true);
+        assert(i == 0);
+
+        assert(stack_pop(stack, &i) == false);
+
+        assert(stack_empty(stack) == true);
+
+        assert(stack[0].sz == 10);
+        assert(stack[0].p == 0);
+
+        for ( int i = 0; i != 23; ++i )
+                stack_push(stack, i);
+
+        assert(stack[0].sz == 33);
+        assert(stack[0].p == 23);
 
         stack_free(stack);
+}
 
+int
+main()
+{
+        test_stack();
         return EXIT_SUCCESS;
 }