Rework API completely

test/runtime/tree_test.cc

@@ -0,0 +1,200 @@
+#include "test_helper.h"
+#include "runtime/alloc.h"
+#include "helpers/record_alloc.h"
+#include "helpers/stream_methods.h"
+#include "helpers/tree_helpers.h"
+#include "helpers/point_helpers.h"
+#include "helpers/spy_logger.h"
+#include "helpers/stderr_logger.h"
+#include "helpers/spy_input.h"
+#include "helpers/load_language.h"
+
+TSPoint point(uint32_t row, uint32_t column) {
+  TSPoint result = {row, column};
+  return result;
+}
+
+START_TEST
+
+describe("Tree", [&]() {
+  TSParser *parser;
+  SpyInput *input;
+  TSTree *tree;
+
+  before_each([&]() {
+    parser = ts_parser_new();
+  });
+
+  after_each([&]() {
+    ts_parser_delete(parser);
+  });
+
+  auto assert_root_node = [&](const string &expected) {
+    TSNode node = ts_tree_root_node(tree);
+    char *node_string = ts_node_string(node);
+    string actual(node_string);
+    ts_free(node_string);
+    AssertThat(actual, Equals(expected));
+  };
+
+  describe("get_changed_ranges()", [&]() {
+    before_each([&]() {
+      ts_parser_set_language(parser, load_real_language("javascript"));
+      input = new SpyInput("{a: null};\n", 3);
+      tree = ts_parser_parse(parser, nullptr, input->input());
+
+      assert_root_node(
+        "(program (expression_statement (object (pair (property_identifier) (null)))))"
+      );
+    });
+
+    after_each([&]() {
+      ts_tree_delete(tree);
+      delete input;
+    });
+
+    auto get_changed_ranges_for_edit = [&](function<TSInputEdit()> fn) -> vector<TSRange> {
+      TSInputEdit edit = fn();
+      ts_tree_edit(tree, &edit);
+
+      uint32_t range_count = 0;
+      TSTree *new_tree = ts_parser_parse(parser, tree, input->input());
+      TSRange *ranges = ts_tree_get_changed_ranges(tree, new_tree, &range_count);
+      ts_tree_delete(tree);
+      tree = new_tree;
+
+      vector<TSRange> result;
+      for (size_t i = 0; i < range_count; i++) {
+        result.push_back(ranges[i]);
+      }
+
+      ts_free(ranges);
+      return result;
+    };
+
+    it("reports changes when one token has been updated", [&]() {
+      // Replace `null` with `nothing`
+      auto ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(input->content.find("ull"), 1, "othing");
+      });
+      AssertThat(ranges, Equals(vector<TSRange>({
+        TSRange{
+          point(0, input->content.find("nothing")),
+          point(0, input->content.find("}"))
+        },
+      })));
+
+      // Replace `nothing` with `null` again
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->undo();
+      });
+      AssertThat(ranges, Equals(vector<TSRange>({
+        TSRange{
+          point(0, input->content.find("null")),
+          point(0, input->content.find("}"))
+        },
+      })));
+    });
+
+    it("reports no changes when leading whitespace has changed (regression)", [&]() {
+      input->chars_per_chunk = 80;
+
+      // Insert leading whitespace
+      auto ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(0, 0, "\n");
+      });
+      assert_root_node(
+        "(program (expression_statement (object (pair (property_identifier) (null)))))"
+      );
+      AssertThat(ranges, IsEmpty());
+
+      // Remove leading whitespace
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->undo();
+      });
+      assert_root_node(
+        "(program (expression_statement (object (pair (property_identifier) (null)))))"
+      );
+      AssertThat(ranges, IsEmpty());
+
+      // Insert leading whitespace again
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(0, 0, "\n");
+      });
+      assert_root_node(
+        "(program (expression_statement (object (pair (property_identifier) (null)))))"
+      );
+      AssertThat(ranges, IsEmpty());
+    });
+
+    it("reports changes when tokens have been appended", [&]() {
+      // Add a second key-value pair
+      auto ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(input->content.find("}"), 0, ", b: false");
+      });
+      AssertThat(ranges, Equals(vector<TSRange>({
+        TSRange{
+          point(0, input->content.find(",")),
+          point(0, input->content.find("}"))
+        },
+      })));
+
+      // Add a third key-value pair in between the first two
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(input->content.find(", b"), 0, ", c: 1");
+      });
+      assert_root_node(
+        "(program (expression_statement (object "
+          "(pair (property_identifier) (null)) "
+          "(pair (property_identifier) (number)) "
+          "(pair (property_identifier) (false)))))"
+      );
+      AssertThat(ranges, Equals(vector<TSRange>({
+        TSRange{
+          point(0, input->content.find(", c")),
+          point(0, input->content.find(", b"))
+        },
+      })));
+
+      // Delete the middle pair.
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->undo();
+      });
+      assert_root_node(
+        "(program (expression_statement (object "
+          "(pair (property_identifier) (null)) "
+          "(pair (property_identifier) (false)))))"
+      );
+      AssertThat(ranges, IsEmpty());
+
+      // Delete the second pair.
+      ranges = get_changed_ranges_for_edit([&]() {
+        return input->undo();
+      });
+      assert_root_node(
+        "(program (expression_statement (object "
+          "(pair (property_identifier) (null)))))"
+      );
+      AssertThat(ranges, IsEmpty());
+    });
+
+    it("reports changes when trees have been wrapped", [&]() {
+      // Wrap the object in an assignment expression.
+      auto ranges = get_changed_ranges_for_edit([&]() {
+        return input->replace(input->content.find("null"), 0, "b === ");
+      });
+      assert_root_node(
+        "(program (expression_statement (object "
+          "(pair (property_identifier) (binary_expression (identifier) (null))))))"
+      );
+      AssertThat(ranges, Equals(vector<TSRange>({
+        TSRange{
+          point(0, input->content.find("b ===")),
+          point(0, input->content.find("}"))
+        },
+      })));
+    });
+  });
+});
+
+END_TEST