6 files changed, 58 insertions, 53 deletions
diff --git a/cli/dts/lib.deno.unstable.d.ts b/cli/dts/lib.deno.unstable.d.ts
index 062ec79e7..2904c14f3 100644
--- a/cli/dts/lib.deno.unstable.d.ts
+++ b/cli/dts/lib.deno.unstable.d.ts
@@ -1442,7 +1442,7 @@ declare namespace Deno {
   /**
    * Executes a subprocess, waiting for it to finish and
    * collecting all of its output.
-   * The stdio options are ignored.
+   * Will throw an error if `stdin: "piped"` is passed.
    *
    * ```ts
    * const { status, stdout, stderr } = await Deno.spawn(Deno.execPath(), {
@@ -1464,7 +1464,7 @@ declare namespace Deno {
   /**
    * Synchronously executes a subprocess, waiting for it to finish and
    * collecting all of its output.
-   * The stdio options are ignored.
+   * Will throw an error if `stdin: "piped"` is passed.
    *
    * ```ts
    * const { status, stdout, stderr } = Deno.spawnSync(Deno.execPath(), {
diff --git a/cli/tests/integration/run_tests.rs b/cli/tests/integration/run_tests.rs
index 85363a27f..e6004ba49 100644
--- a/cli/tests/integration/run_tests.rs
+++ b/cli/tests/integration/run_tests.rs
@@ -2764,3 +2764,8 @@ itest!(report_error_handled {
   args: "run --quiet report_error_handled.ts",
   output: "report_error_handled.ts.out",
 });
+
+itest!(spawn_stdout_inherit {
+  args: "run --quiet --unstable -A spawn_stdout_inherit.ts",
+  output: "spawn_stdout_inherit.ts.out",
+});
diff --git a/cli/tests/testdata/spawn_stdout_inherit.ts b/cli/tests/testdata/spawn_stdout_inherit.ts
new file mode 100644
index 000000000..be5f9b7ef
--- /dev/null
+++ b/cli/tests/testdata/spawn_stdout_inherit.ts
@@ -0,0 +1,8 @@
+await Deno.spawn(Deno.execPath(), {
+  args: ["eval", "--quiet", "console.log('Hello, world! 1')"],
+  stdout: "inherit",
+});
+Deno.spawnSync(Deno.execPath(), {
+  args: ["eval", "--quiet", "console.log('Hello, world! 2')"],
+  stdout: "inherit",
+});
diff --git a/cli/tests/testdata/spawn_stdout_inherit.ts.out b/cli/tests/testdata/spawn_stdout_inherit.ts.out
new file mode 100644
index 000000000..474891cf2
--- /dev/null
+++ b/cli/tests/testdata/spawn_stdout_inherit.ts.out
@@ -0,0 +1,2 @@
+Hello, world! 1
+Hello, world! 2
diff --git a/cli/tests/unit/command_test.ts b/cli/tests/unit/command_test.ts
index f7213f034..4b3d5bd11 100644
--- a/cli/tests/unit/command_test.ts
+++ b/cli/tests/unit/command_test.ts
@@ -470,46 +470,6 @@ Deno.test(
 
 Deno.test(
   { permissions: { run: true, read: true } },
-  async function spawnOverrideStdio() {
-    const { stdout, stderr } = await Deno.spawn(Deno.execPath(), {
-      args: [
-        "eval",
-        "console.log('hello'); console.error('world')",
-      ],
-      stdin: "piped",
-      stdout: "null",
-      stderr: "null",
-    });
-
-    // @ts-ignore: for testing
-    assertEquals(new TextDecoder().decode(stdout), "hello\n");
-    // @ts-ignore: for testing
-    assertEquals(new TextDecoder().decode(stderr), "world\n");
-  },
-);
-
-Deno.test(
-  { permissions: { run: true, read: true } },
-  function spawnSyncOverrideStdio() {
-    const { stdout, stderr } = Deno.spawnSync(Deno.execPath(), {
-      args: [
-        "eval",
-        "console.log('hello'); console.error('world')",
-      ],
-      stdin: "piped",
-      stdout: "null",
-      stderr: "null",
-    });
-
-    // @ts-ignore: for testing
-    assertEquals(new TextDecoder().decode(stdout), "hello\n");
-    // @ts-ignore: for testing
-    assertEquals(new TextDecoder().decode(stderr), "world\n");
-  },
-);
-
-Deno.test(
-  { permissions: { run: true, read: true } },
   async function spawnEnv() {
     const { stdout } = await Deno.spawn(Deno.execPath(), {
       args: [
@@ -685,3 +645,25 @@ Deno.test(
     }
   },
 );
+
+Deno.test(async function spawnStdinPipedFails() {
+  await assertRejects(
+    () =>
+      Deno.spawn("id", {
+        stdin: "piped",
+      }),
+    TypeError,
+    "Piped stdin is not supported for this function, use 'Deno.spawnChild()' instead",
+  );
+});
+
+Deno.test(function spawnSyncStdinPipedFails() {
+  assertThrows(
+    () =>
+      Deno.spawnSync("id", {
+        stdin: "piped",
+      }),
+    TypeError,
+    "Piped stdin is not supported for this function, use 'Deno.spawnChild()' instead",
+  );
+});
diff --git a/runtime/js/40_spawn.js b/runtime/js/40_spawn.js
index c55ce657d..3b609be8b 100644
--- a/runtime/js/40_spawn.js
+++ b/runtime/js/40_spawn.js
@@ -166,13 +166,13 @@
     }
   }
 
-  function spawn(command, options) { // TODO(@crowlKats): more options (like input)?
-    return spawnChild(command, {
-      ...options,
-      stdin: "null",
-      stdout: "piped",
-      stderr: "piped",
-    }).output();
+  function spawn(command, options) {
+    if (options?.stdin === "piped") {
+      throw new TypeError(
+        "Piped stdin is not supported for this function, use 'Deno.spawnChild()' instead",
+      );
+    }
+    return spawnChild(command, options).output();
   }
 
   function spawnSync(command, {
@@ -182,7 +182,15 @@
     env = {},
     uid = undefined,
     gid = undefined,
-  } = {}) { // TODO(@crowlKats): more options (like input)?
+    stdin = "null",
+    stdout = "piped",
+    stderr = "piped",
+  } = {}) {
+    if (stdin === "piped") {
+      throw new TypeError(
+        "Piped stdin is not supported for this function, use 'Deno.spawnChild()' instead",
+      );
+    }
     return core.opSync("op_spawn_sync", {
       cmd: pathFromURL(command),
       args: ArrayPrototypeMap(args, String),
@@ -191,9 +199,9 @@
       env: ObjectEntries(env),
       uid,
       gid,
-      stdin: "null",
-      stdout: "piped",
-      stderr: "piped",
+      stdin,
+      stdout,
+      stderr,
     });
   }