Don't check for empty stack as often

src/test.cpp

@@ -563,9 +563,6 @@ private:
   }
 
   static Status keepGoing(Parser2 *self) {
-    if (self->empty()) {
-      return S_OK;
-    }
     if (self->len() == 0) {
       return S_AGAIN;
     }
@@ -578,6 +575,9 @@ private:
       return s;
     }
     self->pop();
+    if (self->empty()) {
+      return S_OK;
+    }
     MUSTTAIL return keepGoing(self);
   }
   static Status stringFromEscape(Parser2 *self) {
@@ -585,6 +585,9 @@ private:
       return s;
     }
     self->pop();
+    if (self->empty()) {
+      return S_OK;
+    }
     MUSTTAIL return keepGoing(self);
   }
   static Status number(Parser2 *self) {
@@ -592,6 +595,9 @@ private:
       return s;
     }
     self->pop();
+    if (self->empty()) {
+      return S_OK;
+    }
     MUSTTAIL return keepGoing(self);
   }
   static Status value(Parser2 *self) {
@@ -656,6 +662,9 @@ private:
       ++self->buf;
       self->pop();
       self->callbacks->on_end_array(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     } else {
       self->pop();
@@ -671,6 +680,9 @@ private:
       ++self->buf;
       self->pop();
       self->callbacks->on_end_object(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     } else if (*self->buf == '"') {
       self->callbacks->on_begin_string(self->data);
@@ -698,6 +710,9 @@ private:
       ++self->buf;
       self->pop();
       self->callbacks->on_end_array(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     }
     return S_REJECT;
@@ -716,6 +731,9 @@ private:
       ++self->buf;
       self->pop();
       self->callbacks->on_end_object(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     }
     return S_REJECT;
@@ -724,6 +742,9 @@ private:
     if (*self->buf++ == 'e') {
       self->pop();
       self->callbacks->on_true_literal(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     }
     return S_REJECT;
@@ -732,6 +753,9 @@ private:
     if (*self->buf++ == 'e') {
       self->pop();
       self->callbacks->on_false_literal(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     }
     return S_REJECT;
@@ -740,6 +764,9 @@ private:
     if (*self->buf++ == 'l') {
       self->pop();
       self->callbacks->on_null_literal(self->data);
+      if (self->empty()) {
+        return S_OK;
+      }
       MUSTTAIL return keepGoing(self);
     }
     return S_REJECT;