Add buffer functions

Author: skanehira

vim/buffer.ts

@@ -0,0 +1,30 @@
+import { Denops } from "../deps.ts";
+
+export async function bufadd(denops: Denops, name: string): Promise<number> {
+  const bufnr = await denops.eval("bufadd(name)", { name: name });
+  return bufnr as number;
+}
+
+export async function bufexists(
+  denops: Denops,
+  name: string | number,
+): Promise<boolean> {
+  const result = await denops.eval("bufexists(name)", { name: name }) as number;
+  return result ? true : false;
+}
+
+export class BufferHelper {
+  #denops: Denops;
+
+  constructor(denops: Denops) {
+    this.#denops = denops;
+  }
+
+  async bufadd(name: string): Promise<number> {
+    return await bufadd(this.#denops, name);
+  }
+
+  async bufexists(name: string | number): Promise<boolean> {
+    return await bufexists(this.#denops, name);
+  }
+}

vim/vim.ts

@@ -2,6 +2,7 @@ import { Context, Denops, Dispatcher } from "../deps.ts";
 import { execute } from "./execute.ts";
 import { autocmd, AutocmdHelper } from "./autocmd.ts";
 import { VariableHelper } from "./variable.ts";
+import { BufferHelper } from "./buffer.ts";
 import { load } from "./load.ts";
 
 /**
@@ -23,13 +24,16 @@ export class Vim {
   readonly t: VariableHelper;
   readonly v: VariableHelper;
 
+  readonly buffer: BufferHelper;
+
   constructor(denops: Denops) {
     this.#denops = denops;
     this.g = new VariableHelper(denops, "g");
     this.b = new VariableHelper(denops, "b");
     this.w = new VariableHelper(denops, "w");
     this.t = new VariableHelper(denops, "t");
     this.v = new VariableHelper(denops, "v");
+    this.buffer = new BufferHelper(denops);
   }
 
   /**