Change behaviour.

README.md

@@ -179,19 +179,37 @@ const finalText = await $`echo ${result}`.text();
 console.log(finalText); // 1
 ```
 
+#### JavaScript objects to redirects
+
 You can also provide JavaScript objects to shell output redirects:
 
 ```ts
 const buffer = new Uint8Array(2);
-await $`echo 1 && (echo 2 > ${buffer}) && echo 3`;
-console.log(buffer); // Uint8Array(2) [ 50, 10 ]
+await $`echo 1 && (echo 2 > ${buffer}) && echo 3`; // 1\n3\n
+console.log(buffer); // Uint8Array(2) [ 50, 10 ] (2\n)
 ```
 
+Supported objects: `Uint8Array`, `PathRef`, `WritableStream`, function that returns a `WritableStream`, any object that implements `[$.symbols.writable](): WritableStream`
+
 Or input redirects:
 
 ```ts
+// strings
+const data = "my data in a string";
+const bytes = await $`gzip < ${data}`;
+
+// paths
+const path = $.path("file.txt");
+const bytes = await $`gzip < ${path}`;
+
+// requests (this example does not make the request until after 5 seconds)
+const request = $.request("https://plugins.dprint.dev/info.json")
+  .showProgress(); // show a progress bar while downloading
+const bytes = await $`sleep 5 && gzip < ${request}`.bytes();
 ```
 
+Supported objects: `string`, `Uint8Array`, `PathRef`, `RequestBuilder`, `ReadableStream`, function that returns a `ReadableStream`, any object that implements `[$.symbols.readable](): ReadableStream`
+
 ### Providing stdin
 
 ```ts

mod.test.ts

@@ -1269,6 +1269,12 @@ Deno.test("input redirects with provided object", async () => {
     const output = await $`cat - < ${stream}`.text();
     assertEquals(output, text);
   }
+  // string
+  {
+    const text = "testing".repeat(1000);
+    const output = await $`cat - < ${text}`.text();
+    assertEquals(output, text);
+  }
   // bytes
   {
     const text = "testing".repeat(1000);
@@ -1361,6 +1367,14 @@ Deno.test("output redirect with provided object", async () => {
     await $`echo 1 > ${() => writableStream}`;
     assertEquals(chunks, [new Uint8Array([49, 10])]);
   }
+  {
+    assertThrows(
+      () => $`echo 1 > ${"test.txt"}`,
+      Error,
+      "Failed resolving expression in command. Cannot provide strings to output " +
+        "redirects. Did you mean to provide a path instead via the `$.path(...)` API?",
+    );
+  }
 });
 
 Deno.test("shebang support", async (t) => {

src/command.ts

@@ -1252,8 +1252,17 @@ function templateInner(
         const expr = exprs[i];
         const inputOrOutputRedirect = detectInputOrOutputRedirect(text);
         if (inputOrOutputRedirect === "<") {
-          if (typeof expr === "string" || expr instanceof PathRef) {
+          if (expr instanceof PathRef) {
             text += templateLiteralExprToString(expr, escape);
+          } else if (typeof expr === "string") {
+            handleReadableStream(() =>
+              new ReadableStream({
+                start(controller) {
+                  controller.enqueue(new TextEncoder().encode(expr));
+                  controller.close();
+                },
+              })
+            );
           } else if (expr instanceof ReadableStream) {
             handleReadableStream(() => expr);
           } else if (expr?.[symbols.readable]) {
@@ -1303,7 +1312,7 @@ function templateInner(
             throw new Error("Unsupported object provided to input redirect.");
           }
         } else if (inputOrOutputRedirect === ">") {
-          if (typeof expr === "string" || expr instanceof PathRef) {
+          if (expr instanceof PathRef) {
             text += templateLiteralExprToString(expr, escape);
           } else if (expr instanceof WritableStream) {
             handleWritableStream(() => expr);
@@ -1349,6 +1358,10 @@ function templateInner(
                 );
               }
             });
+          } else if (typeof expr === "string") {
+            throw new Error(
+              "Cannot provide strings to output redirects. Did you mean to provide a path instead via the `$.path(...)` API?",
+            );
           } else {
             throw new Error("Unsupported object provided to output redirect.");
           }