fix: better error message when providing a command builder to an expr

mod.test.ts

@@ -2108,12 +2108,24 @@ Deno.test("should support empty quoted string", async () => {
   assertEquals(output, " test ");
 });
 
-Deno.test("esnure deprecated PathRef export still works", () => {
+Deno.test("ensure deprecated PathRef export still works", () => {
   const path = new PathRef("hello");
   assert(path instanceof Path);
   assert(path instanceof PathRef);
 });
 
+Deno.test("nice error message when not awaiting a CommandBuilder", async () => {
+  await assertRejects(
+    async () => {
+      const cmd = $`echo 1`;
+      return await $`echo ${cmd}`;
+    },
+    Error,
+    "Providing a command builder is not yet supported (https://github.com/dsherret/dax/issues/239). " +
+      "Await the command builder's text before using it in an expression (ex. await $`cmd`.text()).",
+  );
+});
+
 function ensurePromiseNotResolved(promise: Promise<unknown>) {
   return new Promise<void>((resolve, reject) => {
     promise.then(() => reject(new Error("Promise was resolved")));

mod.ts

@@ -2,7 +2,7 @@ import {
   CommandBuilder,
   escapeArg,
   getRegisteredCommandNamesSymbol,
-  setCommandTextAndFdsSymbol,
+  setCommandTextStateSymbol,
   template,
   templateRaw,
 } from "./src/command.ts";
@@ -632,8 +632,8 @@ function build$FromState<TExtras extends ExtrasObject = {}>(state: $State<TExtra
   };
   const result = Object.assign(
     (strings: TemplateStringsArray, ...exprs: any[]) => {
-      const { text, streams } = template(strings, exprs);
-      return state.commandBuilder.getValue()[setCommandTextAndFdsSymbol](text, streams);
+      const textState = template(strings, exprs);
+      return state.commandBuilder.getValue()[setCommandTextStateSymbol](textState);
     },
     helperObject,
     logDepthObj,
@@ -764,8 +764,8 @@ function build$FromState<TExtras extends ExtrasObject = {}>(state: $State<TExtra
         return state.requestBuilder.url(url);
       },
       raw(strings: TemplateStringsArray, ...exprs: any[]) {
-        const { text, streams } = templateRaw(strings, exprs);
-        return state.commandBuilder.getValue()[setCommandTextAndFdsSymbol](text, streams);
+        const textState = templateRaw(strings, exprs);
+        return state.commandBuilder.getValue()[setCommandTextStateSymbol](textState);
       },
       withRetries<TReturn>(opts: RetryOptions<TReturn>): Promise<TReturn> {
         return withRetries(result, state.errorLogger.getValue(), opts);

src/command.ts

@@ -103,7 +103,7 @@ const builtInCommands = {
 /** @internal */
 export const getRegisteredCommandNamesSymbol: unique symbol = Symbol();
 /** @internal */
-export const setCommandTextAndFdsSymbol: unique symbol = Symbol();
+export const setCommandTextStateSymbol: unique symbol = Symbol();
 
 /**
  * Underlying builder API for executing commands.
@@ -583,12 +583,9 @@ export class CommandBuilder implements PromiseLike<CommandResult> {
   }
 
   /** @internal */
-  [setCommandTextAndFdsSymbol](text: string, fds: StreamFds | undefined) {
+  [setCommandTextStateSymbol](textState: CommandBuilderStateCommand) {
     return this.#newWithState((state) => {
-      state.command = {
-        text,
-        fds,
-      };
+      state.command = textState;
     });
   }
 }
@@ -1240,7 +1237,7 @@ function templateInner(
   strings: TemplateStringsArray,
   exprs: any[],
   escape: ((arg: string) => string) | undefined,
-) {
+): CommandBuilderStateCommand {
   let nextStreamFd = 3;
   let text = "";
   let streams: StreamFds | undefined;
@@ -1380,7 +1377,7 @@ function templateInner(
   }
   return {
     text,
-    streams,
+    fds: streams,
   };
 
   function handleReadableStream(createStream: () => ReadableStream) {
@@ -1440,6 +1437,11 @@ function templateLiteralExprToString(expr: any, escape: ((arg: string) => string
   } else if (expr instanceof CommandResult) {
     // remove last newline
     result = expr.stdout.replace(/\r?\n$/, "");
+  } else if (expr instanceof CommandBuilder) {
+    throw new Error(
+      "Providing a command builder is not yet supported (https://github.com/dsherret/dax/issues/239). " +
+        "Await the command builder's text before using it in an expression (ex. await $`cmd`.text()).",
+    );
   } else if (typeof expr === "object" && expr.toString === Object.prototype.toString) {
     throw new Error("Provided object does not override `toString()`.");
   } else {