Merge pull request #5 from dlants/lsp-improvements-tests

enhance listBuffers tool

Author: dlants

bun/tea/tea.ts

@@ -88,14 +88,17 @@ export function createApp<Model, Msg>({
     try {
       const [nextModel, thunk] = update(msg, currentState.model);
 
-      if (thunk && !suppressThunks) {
-        nvim.logger?.debug(`starting thunk`);
-        thunk(dispatch).catch((err) => {
-          nvim.logger?.error(err as Error);
-        });
+      if (thunk) {
+        if (suppressThunks) {
+          nvim.logger?.debug(`thunk suppressed`);
+        } else {
+          nvim.logger?.debug(`starting thunk`);
+          thunk(dispatch).catch((err) => {
+            nvim.logger?.error(err as Error);
+          });
+        }
       }
 
-
       currentState = { status: "running", model: nextModel };
 
       render();
@@ -110,13 +113,15 @@ export function createApp<Model, Msg>({
   };
 
   function render() {
-    nvim.logger?.info(`render`)
+    nvim.logger?.info(`render`);
     if (renderPromise) {
       reRender = true;
-      nvim.logger?.info(`re-render scheduled`)
+      nvim.logger?.info(`re-render scheduled`);
     } else {
       if (root) {
-        nvim.logger?.info(`init renderPromise of state ${JSON.stringify(currentState, null, 2)}`)
+        nvim.logger?.info(
+          `init renderPromise of state ${JSON.stringify(currentState, null, 2)}`,
+        );
         renderPromise = root
           .render({ currentState, dispatch })
           .catch((err) => {

bun/test/driver.ts

@@ -141,4 +141,8 @@ vim.rpcnotify(${this.nvim.channelId}, "magentaKey", "${key}")
       { timeout: 200 },
     );
   }
+
+  async editFile(filePath: string): Promise<void> {
+    await this.nvim.call("nvim_exec2", [`edit ${filePath}`, {}]);
+  }
 }

bun/test/fixtures/poem2.txt

@@ -0,0 +1,4 @@
+Moonlight whispers through the trees,
+Silver shadows dance with ease.
+Stars above like diamonds bright,
+Paint their stories in the night.

bun/tools/listBuffers.spec.ts

@@ -5,8 +5,66 @@ import { describe, it, expect } from "bun:test";
 import { pos } from "../tea/view.ts";
 import { NvimBuffer } from "../nvim/buffer.ts";
 import { withNvimClient } from "../test/preamble.ts";
+import { withDriver } from "../test/preamble";
+import { pollUntil } from "../utils/async.ts";
 
 describe("bun/tools/listBuffers.spec.ts", () => {
+  it("listBuffers end-to-end", async () => {
+    await withDriver(async (driver) => {
+      await driver.editFile("bun/test/fixtures/poem.txt");
+      await driver.editFile("bun/test/fixtures/poem2.txt");
+      await driver.showSidebar();
+
+      await driver.assertWindowCount(3);
+
+      await driver.inputMagentaText(`Try listing some buffers`);
+      await driver.send();
+
+      const toolRequestId = "id" as ToolRequestId;
+      await driver.mockAnthropic.respond({
+        stopReason: "tool_use",
+        text: "ok, here goes",
+        toolRequests: [
+          {
+            status: "ok",
+            value: {
+              type: "tool_use",
+              id: toolRequestId,
+              name: "list_buffers",
+              input: {},
+            },
+          },
+        ],
+      });
+
+      const result = await pollUntil(() => {
+        const state = driver.magenta.chatApp.getState();
+        if (state.status != "running") {
+          throw new Error(`app crashed`);
+        }
+
+        const toolWrapper = state.model.toolManager.toolWrappers[toolRequestId];
+        if (!toolWrapper) {
+          throw new Error(
+            `could not find toolWrapper with id ${toolRequestId}`,
+          );
+        }
+
+        if (toolWrapper.model.state.state != "done") {
+          throw new Error(`Request not done`);
+        }
+
+        return toolWrapper.model.state.result;
+      });
+
+      expect(result).toEqual({
+        tool_use_id: toolRequestId,
+        type: "tool_result",
+        content: `bun/test/fixtures/poem.txt\nactive bun/test/fixtures/poem2.txt`,
+      });
+    });
+  });
+
   it("render the listBuffers tool.", async () => {
     await withNvimClient(async (nvim) => {
       const buffer = await NvimBuffer.create(false, true, nvim);
@@ -40,9 +98,7 @@ describe("bun/tools/listBuffers.spec.ts", () => {
 
       const content = (await buffer.getLines({ start: 0, end: -1 })).join("\n");
 
-      expect(
-        content,
-      ).toBe(`⚙️ Grabbing buffers...`);
+      expect(content).toBe(`⚙️ Grabbing buffers...`);
 
       app.dispatch({
         type: "finish",
@@ -54,9 +110,9 @@ describe("bun/tools/listBuffers.spec.ts", () => {
       });
 
       await mountedApp.waitForRender();
-      expect(
-        (await buffer.getLines({ start: 0, end: -1 })).join("\n")
-      ).toBe(`✅ Finished getting buffers.`);
+      expect((await buffer.getLines({ start: 0, end: -1 })).join("\n")).toBe(
+        `✅ Finished getting buffers.`,
+      );
     });
   });
 });

bun/tools/listBuffers.ts

@@ -1,12 +1,11 @@
 import * as Anthropic from "@anthropic-ai/sdk";
-import path from "path";
 import { assertUnreachable } from "../utils/assertUnreachable.ts";
 import type { Thunk, Update } from "../tea/tea.ts";
 import { d, type VDOMNode } from "../tea/view.ts";
 import { type ToolRequestId } from "./toolManager.ts";
 import { type Result } from "../utils/result.ts";
-import { getAllBuffers, getcwd } from "../nvim/nvim.ts";
 import type { Nvim } from "bunvim";
+import { parseLsResponse } from "../utils/lsBuffers.ts";
 
 export type Model = {
   type: "list_buffers";
@@ -57,21 +56,35 @@ export function initModel(
   return [
     model,
     async (dispatch) => {
-      const buffers = await getAllBuffers(context.nvim);
-      const cwd = await getcwd(context.nvim);
-      const bufferPaths = await Promise.all(
-        buffers.map(async (buffer) => {
-          const fullPath = await buffer.getName();
-          return fullPath.length ? path.relative(cwd, fullPath) : "";
-        }),
-      );
+      const lsResponse = await context.nvim.call("nvim_exec2", [
+        "ls",
+        { output: true },
+      ]);
+
+      const result = parseLsResponse(lsResponse.output as string);
+      const content = result
+        .map((bufEntry) => {
+          let out = "";
+          if (bufEntry.flags.active) {
+            out += "active ";
+          }
+          if (bufEntry.flags.modified) {
+            out += "modified ";
+          }
+          if (bufEntry.flags.terminal) {
+            out += "terminal ";
+          }
+          out += bufEntry.filePath;
+          return out;
+        })
+        .join("\n");
 
       dispatch({
         type: "finish",
         result: {
           type: "tool_result",
           tool_use_id: request.id,
-          content: bufferPaths.filter((p) => p.length).join("\n"),
+          content,
         },
       });
     },
@@ -108,7 +121,9 @@ export function getToolResult(
 
 export const spec: Anthropic.Anthropic.Tool = {
   name: "list_buffers",
-  description: `List the file paths of all the buffers the user currently has open. This can be useful to understand the context of what the user is trying to do.`,
+  description: `List all the buffers the user currently has open.
+This will be similar to the output of :buffers in neovim, so buffers will be listed in the order they were opened, with the most recent buffers last.
+This can be useful to understand the context of what the user is trying to do.`,
   input_schema: {
     type: "object",
     properties: {},

bun/utils/lsBuffers.ts

@@ -0,0 +1,55 @@
+interface BufferFlags {
+  hidden: boolean; // 'h' flag
+  active: boolean; // 'a' flag
+  current: boolean; // '%' flag
+  alternate: boolean; // '#' flag
+  modified: boolean; // '+' flag
+  readonly: boolean; // '-' flag
+  terminal: boolean; // 'terminal' flag
+}
+
+interface BufferEntry {
+  id: number; // Buffer number
+  flags: BufferFlags; // Parsed status flags
+  filePath: string; // File path
+  lineNumber: number; // Current line number
+}
+
+function parseFlags(flagStr: string): BufferFlags {
+  return {
+    hidden: flagStr.includes("h"),
+    active: flagStr.includes("a"),
+    current: flagStr.includes("%"),
+    alternate: flagStr.includes("#"),
+    modified: flagStr.includes("+"),
+    readonly: flagStr.includes("-"),
+    terminal: flagStr.includes("t"),
+  };
+}
+
+/**
+ * Parses the output of Neovim's :buffers command into structured data
+ *lsResponse.output is like:  "  1  h   \"bun/test/fixtures/poem.txt\"   line 1\n  2  a   \"bun/test/fixtures/poem2.txt\"  line 1"
+ * see docfiles for :buffers to understand output format
+ */
+export function parseLsResponse(response: string): BufferEntry[] {
+  // Split the response into lines and filter out empty lines
+  const lines = response.split("\n").filter((line) => line.trim());
+
+  return lines.map((line) => {
+    // Remove extra whitespace and split by multiple spaces
+    const parts = line.trim().split(/\s+/);
+
+    // Extract filepath by finding the quoted string
+    const filepathStart = line.indexOf('"');
+    const filepathEnd = line.lastIndexOf('"');
+    const filePath = line.slice(filepathStart + 1, filepathEnd);
+
+    return {
+      id: parseInt(parts[0], 10),
+      flags: parseFlags(parts[1]),
+      filePath,
+      lineNumber: parseInt(parts[parts.length - 1], 10),
+    };
+  });
+}