perf(editor): cache executable statement ranges for large SQL scrolling

Co-authored-by: staff <staff@qimaos-MacBook-Pro.local>

apps/desktop/src/lib/__tests__/executableStatementRangeCache.spec.ts

@@ -0,0 +1,43 @@
+import { Text } from "@codemirror/state";
+import { describe, expect, it, vi } from "vitest";
+import { executableStatementRangeCacheForDoc, executableStatementRangeStartingAt, type ExecutableStatementRangeParser } from "@/lib/executableStatementRangeCache";
+
+describe("executableStatementRangeCacheForDoc", () => {
+  it("reuses parsed executable statement ranges for the same document and database type", () => {
+    const doc = Text.of(["SELECT 1;", "SELECT 2;"]);
+    const parse = vi.fn<ExecutableStatementRangeParser>(() => [
+      { from: 0, to: 8, sql: "SELECT 1" },
+      { from: 10, to: 18, sql: "SELECT 2" },
+    ]);
+
+    const first = executableStatementRangeCacheForDoc(null, doc, "mysql", parse);
+    const second = executableStatementRangeCacheForDoc(first, doc, "mysql", parse);
+
+    expect(second).toBe(first);
+    expect(parse).toHaveBeenCalledTimes(1);
+    expect(executableStatementRangeStartingAt(second, 10)?.sql).toBe("SELECT 2");
+  });
+
+  it("rebuilds the cache when the document instance changes", () => {
+    const firstDoc = Text.of(["SELECT 1;"]);
+    const secondDoc = Text.of(["SELECT 1;"]);
+    const parse = vi.fn<ExecutableStatementRangeParser>(() => [{ from: 0, to: 8, sql: "SELECT 1" }]);
+
+    const first = executableStatementRangeCacheForDoc(null, firstDoc, "mysql", parse);
+    const second = executableStatementRangeCacheForDoc(first, secondDoc, "mysql", parse);
+
+    expect(second).not.toBe(first);
+    expect(parse).toHaveBeenCalledTimes(2);
+  });
+
+  it("rebuilds the cache when the database type changes", () => {
+    const doc = Text.of(["SELECT 1;"]);
+    const parse = vi.fn<ExecutableStatementRangeParser>(() => [{ from: 0, to: 8, sql: "SELECT 1" }]);
+
+    const mysql = executableStatementRangeCacheForDoc(null, doc, "mysql", parse);
+    const postgres = executableStatementRangeCacheForDoc(mysql, doc, "postgres", parse);
+
+    expect(postgres).not.toBe(mysql);
+    expect(parse).toHaveBeenCalledTimes(2);
+  });
+});