💥 Remove "variables" entry from dict getbufnr() returns

`getbufnr()` function have dictionaries of buffer local variables in its
return value.  Therefore, when there's a funcref in buffer local
variables, denops will fail to send the return value back to the deno
world.
This behavior is inconvenient, make denops-std's `getbufnr()` omit the
"variables" entries from the return value.

Author: mityu

function/buffer.ts

@@ -414,6 +414,9 @@ export async function deletebufline(
  *                             name  sign name
  *         variables       A reference to the dictionary with
  *                         buffer-local variables.
+ *                         CAUTION: Different from the builtin getbufnr()
+ *                         function, denops-std's getbufnr() function doesn't
+ *                         return this entry.
  *         windows         List of `window-ID`s that display this
  *                         buffer
  *         popups          List of popup `window-ID`s that
@@ -437,6 +440,10 @@ export async function deletebufline(
  * Can also be used as a `method`:
  *
  *     GetBufnr()->getbufinfo()
+ *
+ * CAUTION: Different from the builtin getbufnr() function, denops-std's
+ * getbufnr() function omits the "variables" entry from the returned
+ * dictionary.
  */
 export function getbufinfo(
   denops: Denops,
@@ -450,7 +457,12 @@ export async function getbufinfo(
   denops: Denops,
   ...args: unknown[]
 ): Promise<BufInfo[]> {
-  const bufinfos = await denops.call("getbufinfo", ...args) as Record<
+  const bufinfos = await denops.eval(
+    "map(call('getbufinfo', l:args), {_, v -> filter(v, {k -> k !=# 'variables'})})",
+    {
+      args: args,
+    },
+  ) as Record<
     keyof BufInfo,
     unknown
   >[];

function/buffer_test.ts

@@ -1,4 +1,4 @@
-import { assertEquals } from "@std/assert";
+import { assertEquals, assertFalse } from "@std/assert";
 import { assert, is } from "@core/unknownutil";
 import { test } from "@denops/test";
 import type { BufInfo } from "./types.ts";
@@ -61,5 +61,17 @@ test({
       },
     });
     await denops.cmd("1,$bwipeout!");
+
+    await t.step({
+      name: "getbufinfo() will filter buffer-local variables",
+      fn: async () => {
+        await denops.cmd("enew!");
+        await denops.cmd("let b:var = 0");
+
+        const actual = await buffer.getbufinfo(denops);
+        assertEquals(actual.length, 1);
+        assertFalse("variables" in actual[0]);
+      },
+    });
   },
 });