diff --git a/src/runtime/length.h b/src/runtime/length.h
index d4ce259e..9df859d8 100644
--- a/src/runtime/length.h
+++ b/src/runtime/length.h
@@ -12,11 +12,11 @@ typedef struct {
   TSPoint extent;
 } TSLength;
 
-static inline bool ts_length_is_unknown(TSLength self) {
+static inline bool ts_length_has_unknown_chars(TSLength self) {
   return self.bytes > 0 && self.chars == 0;
 }
 
-static inline void ts_length_set_unknown(TSLength *self) {
+static inline void ts_length_set_unknown_chars(TSLength *self) {
   self->chars = 0;
 }
 
@@ -30,7 +30,7 @@ static inline TSLength ts_length_add(TSLength len1, TSLength len2) {
   result.bytes = len1.bytes + len2.bytes;
   result.extent = ts_point_add(len1.extent, len2.extent);
 
-  if (ts_length_is_unknown(len1) || ts_length_is_unknown(len2)) {
+  if (ts_length_has_unknown_chars(len1) || ts_length_has_unknown_chars(len2)) {
     result.chars = 0;
   } else {
     result.chars = len1.chars + len2.chars;
@@ -44,7 +44,7 @@ static inline TSLength ts_length_sub(TSLength len1, TSLength len2) {
   result.bytes = len1.bytes - len2.bytes;
   result.extent = ts_point_sub(len1.extent, len2.extent);
 
-  if (ts_length_is_unknown(len1) || ts_length_is_unknown(len2)) {
+  if (ts_length_has_unknown_chars(len1) || ts_length_has_unknown_chars(len2)) {
     result.chars = 0;
   } else {
     result.chars = len1.chars - len2.chars;
diff --git a/src/runtime/tree.c b/src/runtime/tree.c
index f35b372f..2f0760c6 100644
--- a/src/runtime/tree.c
+++ b/src/runtime/tree.c
@@ -320,14 +320,14 @@ void ts_tree_edit(TSTree *self, const TSInputEdit *edit) {
   self->has_changes = true;
 
   if (edit->start_byte < self->padding.bytes) {
-    ts_length_set_unknown(&self->padding);
+    ts_length_set_unknown_chars(&self->padding);
     if (self->padding.bytes >= old_end_byte) {
       size_t trailing_padding_bytes = self->padding.bytes - old_end_byte;
       TSPoint trailing_padding_extent = ts_point_sub(self->padding.extent, old_end_point);
       self->padding.bytes = new_end_byte + trailing_padding_bytes;
       self->padding.extent = ts_point_add(new_end_point, trailing_padding_extent);
     } else {
-      ts_length_set_unknown(&self->size);
+      ts_length_set_unknown_chars(&self->size);
       size_t removed_content_bytes = old_end_byte - self->padding.bytes;
       TSPoint removed_content_extent = ts_point_sub(old_end_point, self->padding.extent);
       self->size.bytes = self->size.bytes - removed_content_bytes;
@@ -336,11 +336,11 @@ void ts_tree_edit(TSTree *self, const TSInputEdit *edit) {
       self->padding.extent = new_end_point;
     }
   } else if (edit->start_byte == self->padding.bytes && edit->bytes_removed == 0) {
-    ts_length_set_unknown(&self->padding);
+    ts_length_set_unknown_chars(&self->padding);
     self->padding.bytes = self->padding.bytes + edit->bytes_added;
     self->padding.extent = ts_point_add(self->padding.extent, edit->extent_added);
   } else {
-    ts_length_set_unknown(&self->size);
+    ts_length_set_unknown_chars(&self->size);
     size_t trailing_content_bytes = ts_tree_total_bytes(self) - old_end_byte;
     TSPoint trailing_content_extent = ts_point_sub(ts_tree_total_extent(self), old_end_point);
     self->size.bytes = new_end_byte + trailing_content_bytes - self->padding.bytes;