Merge pull request #59 from tree-sitter/input-string-with-length

Input string with length

include/tree_sitter/runtime.h

@@ -104,6 +104,7 @@ void ts_document_set_language(TSDocument *, const TSLanguage *);
 TSInput ts_document_input(TSDocument *);
 void ts_document_set_input(TSDocument *, TSInput);
 void ts_document_set_input_string(TSDocument *, const char *);
+void ts_document_set_input_string_with_length(TSDocument *, const char *, uint32_t);
 TSLogger ts_document_logger(const TSDocument *);
 void ts_document_set_logger(TSDocument *, TSLogger);
 void ts_document_print_debugging_graphs(TSDocument *, bool);

spec/runtime/document_spec.cc

@@ -116,6 +116,17 @@ describe("Document", [&]() {
       AssertThat(spy_input->strings_read, Equals(vector<string>({" [null, 2" })));
     });
 
+    it("allows setting input string with length", [&]() {
+      const char content[] = { '1' };
+      ts_document_set_input_string_with_length(document, content, 1);
+      ts_document_parse(document);
+      TSNode new_root = ts_document_root_node(document);
+      AssertThat(ts_node_end_char(new_root), Equals<size_t>(1));
+      assert_node_string_equals(
+        new_root,
+        "(number)");
+    });
+
     it("reads from the new input correctly when the old input was blank", [&]() {
       ts_document_set_input_string(document, "");
       ts_document_parse(document);

src/runtime/document.c

@@ -77,6 +77,15 @@ void ts_document_set_input_string(TSDocument *self, const char *text) {
   }
 }
 
+void ts_document_set_input_string_with_length(TSDocument *self, const char *text, uint32_t length) {
+  ts_document_invalidate(self);
+  TSInput input = ts_string_input_make_with_length(text, length);
+  ts_document_set_input(self, input);
+  if (input.payload) {
+    self->owns_input = true;
+  }
+}
+
 void ts_document_edit(TSDocument *self, TSInputEdit edit) {
   if (!self->tree)
     return;

src/runtime/string_input.c

@@ -27,13 +27,17 @@ int ts_string_input_seek(void *payload, uint32_t character, uint32_t byte) {
 }
 
 TSInput ts_string_input_make(const char *string) {
+  return ts_string_input_make_with_length(string, strlen(string));
+}
+
+TSInput ts_string_input_make_with_length(const char *string, uint32_t length) {
   TSStringInput *input = ts_malloc(sizeof(TSStringInput));
   if (!input)
     goto error;
 
   input->string = string;
   input->position = 0;
-  input->length = strlen(string);
+  input->length = length;
   return (TSInput){
     .payload = input,
     .read = ts_string_input_read,

src/runtime/string_input.h

@@ -8,6 +8,7 @@ extern "C" {
 #include "tree_sitter/runtime.h"
 
 TSInput ts_string_input_make(const char *);
+TSInput ts_string_input_make_with_length(const char *, uint32_t);
 
 #ifdef __cplusplus
 }