make @file references in custom slash commands more robust (#2203)

Co-authored-by: Adam Spiers <opencode@adamspiers.org>
Co-authored-by: rekram1-node <aidenpcline@gmail.com>

packages/opencode/src/session/file-reference.ts

@@ -0,0 +1,48 @@
+import os from "os"
+import path from "path"
+
+/**
+ * Regular expression to match @ file references in text
+ * Matches @ followed by file paths, excluding commas, periods at end of sentences, and backticks
+ * Does not match when preceded by word characters or backticks (to avoid email addresses and quoted references)
+ */
+export const fileRegex = /(?<![\w`])@(\.?[^\s`,.]*(?:\.[^\s`,.]+)*)/g
+
+/**
+ * File part type for chat input
+ */
+export type FilePart = {
+  type: "file"
+  url: string
+  filename: string
+  mime: string
+}
+
+/**
+ * Processes file references in a template string and returns file parts
+ * @param template - The template string containing @file references
+ * @param basePath - The base path to resolve relative file paths against
+ * @returns Array of file parts for the chat input
+ */
+export function processFileReferences(template: string, basePath: string): FilePart[] {
+  // intentionally doing match regex doing bash regex replacements
+  // this is because bash commands can output "@" references
+  const matches = template.matchAll(fileRegex)
+
+  const parts: FilePart[] = []
+  for (const match of matches) {
+    const filename = match[1]
+    const filepath = filename.startsWith("~/")
+      ? path.join(os.homedir(), filename.slice(2))
+      : path.resolve(basePath, filename)
+
+    parts.push({
+      type: "file",
+      url: `file://${filepath}`,
+      filename,
+      mime: "text/plain",
+    })
+  }
+
+  return parts
+}

packages/opencode/src/session/index.ts

@@ -1,5 +1,4 @@
 import path from "path"
-import os from "os"
 import { spawn } from "child_process"
 import { Decimal } from "decimal.js"
 import { z, ZodSchema } from "zod"
@@ -51,6 +50,7 @@ import { ulid } from "ulid"
 import { defer } from "../util/defer"
 import { Command } from "../command"
 import { $ } from "bun"
+import { processFileReferences } from "./file-reference"
 
 export namespace Session {
   const log = Log.create({ service: "session" })
@@ -1229,7 +1229,6 @@ export namespace Session {
   })
   export type CommandInput = z.infer<typeof CommandInput>
   const bashRegex = /!`([^`]+)`/g
-  const fileRegex = /@([^\s]+)/g
 
   export async function command(input: CommandInput) {
     log.info("command", input)
@@ -1238,10 +1237,6 @@ export namespace Session {
 
     let template = command.template.replace("$ARGUMENTS", input.arguments)
 
-    // intentionally doing match regex doing bash regex replacements
-    // this is because bash commands can output "@" references
-    const fileMatches = template.matchAll(fileRegex)
-
     const bash = Array.from(template.matchAll(bashRegex))
     if (bash.length > 0) {
       const results = await Promise.all(
@@ -1264,19 +1259,8 @@ export namespace Session {
       },
     ] as ChatInput["parts"]
 
-    for (const match of fileMatches) {
-      const filename = match[1]
-      const filepath = filename.startsWith("~/")
-        ? path.join(os.homedir(), filename.slice(2))
-        : path.join(Instance.worktree, filename)
-
-      parts.push({
-        type: "file",
-        url: `file://${filepath}`,
-        filename,
-        mime: "text/plain",
-      })
-    }
+    const fileReferenceParts = processFileReferences(template, Instance.worktree)
+    parts.push(...fileReferenceParts)
 
     return prompt({
       sessionID: input.sessionID,