6 files changed, 47 insertions, 3 deletions
diff --git a/cli/doc/ts_type.rs b/cli/doc/ts_type.rs
index ec1a5e7e9..e1677f13e 100644
--- a/cli/doc/ts_type.rs
+++ b/cli/doc/ts_type.rs
@@ -529,7 +529,7 @@ impl Into<TsTypeDef> for &TsType {
       TsUnionOrIntersectionType(union_or_inter) => union_or_inter.into(),
       TsArrayType(array_type) => array_type.into(),
       TsTupleType(tuple_type) => tuple_type.into(),
-      TsTypeOperator(type_op_type) => type_op_type.into(),
+      TsTypeOperator(type_op_name) => type_op_name.into(),
       TsParenthesizedType(paren_type) => paren_type.into(),
       TsRestType(rest_type) => rest_type.into(),
       TsOptionalType(optional_type) => optional_type.into(),
@@ -737,7 +737,7 @@ pub fn ts_type_ann_to_def(type_ann: &TsTypeAnn) -> TsTypeDef {
     TsUnionOrIntersectionType(union_or_inter) => union_or_inter.into(),
     TsArrayType(array_type) => array_type.into(),
     TsTupleType(tuple_type) => tuple_type.into(),
-    TsTypeOperator(type_op_type) => type_op_type.into(),
+    TsTypeOperator(type_op_name) => type_op_name.into(),
     TsParenthesizedType(paren_type) => paren_type.into(),
     TsRestType(rest_type) => rest_type.into(),
     TsOptionalType(optional_type) => optional_type.into(),
diff --git a/cli/js/deno.ts b/cli/js/deno.ts
index 5bc69fc7b..e4211c23d 100644
--- a/cli/js/deno.ts
+++ b/cli/js/deno.ts
@@ -53,7 +53,7 @@ export {
 export { metrics, Metrics } from "./ops/runtime.ts";
 export { mkdirSync, mkdir, MkdirOptions } from "./ops/fs/mkdir.ts";
 export { connect, listen, Listener, Conn } from "./net.ts";
-export { env, exit, execPath } from "./ops/os.ts";
+export { dir, env, exit, execPath, osName } from "./ops/os.ts";
 export { run, RunOptions, Process, ProcessStatus } from "./process.ts";
 export { DirEntry, readDirSync, readDir } from "./ops/fs/read_dir.ts";
 export { readFileSync, readFile } from "./read_file.ts";
diff --git a/cli/js/lib.deno.unstable.d.ts b/cli/js/lib.deno.unstable.d.ts
index dc50416fc..f425dec56 100644
--- a/cli/js/lib.deno.unstable.d.ts
+++ b/cli/js/lib.deno.unstable.d.ts
@@ -32,6 +32,18 @@ declare namespace Deno {
    * Requires `allow-read` and `allow-write` permissions. */
   export function linkSync(oldpath: string, newpath: string): void;
 
+  /**
+   * Returns the os name.
+   *
+   * ```ts
+   * console.log(Deno.osName());  // e.g. "Linux"
+   * ```
+   *
+   */
+
+  export function osName(): string;
+
+  /** Creates `newpath` as a hard link to `oldpath`.
   /** **UNSTABLE**: This API needs a security review.
    *
    * Creates `newpath` as a hard link to `oldpath`.
diff --git a/cli/js/ops/os.ts b/cli/js/ops/os.ts
index e63d8b358..915106495 100644
--- a/cli/js/ops/os.ts
+++ b/cli/js/ops/os.ts
@@ -72,3 +72,7 @@ export function dir(kind: DirKind): string | null {
 export function execPath(): string {
   return sendSync("op_exec_path");
 }
+
+export function osName(): string {
+  return sendSync("op_name");
+}
diff --git a/cli/ops/os.rs b/cli/ops/os.rs
index ab7ed2876..77c547362 100644
--- a/cli/ops/os.rs
+++ b/cli/ops/os.rs
@@ -20,6 +20,7 @@ pub fn init(i: &mut CoreIsolate, s: &State) {
   i.register_op("op_hostname", s.stateful_json_op(op_hostname));
   i.register_op("op_loadavg", s.stateful_json_op(op_loadavg));
   i.register_op("op_os_release", s.stateful_json_op(op_os_release));
+  i.register_op("op_name", s.stateful_json_op(op_name));
 }
 
 #[derive(Deserialize)]
@@ -206,3 +207,14 @@ fn op_os_release(
   let release = sys_info::os_release().unwrap_or_else(|_| "".to_string());
   Ok(JsonOp::Sync(json!(release)))
 }
+
+fn op_name(
+  state: &State,
+  _args: Value,
+  _zero_copy: &mut [ZeroCopyBuf],
+) -> Result<JsonOp, OpError> {
+  state.check_unstable("Deno.osName");
+  state.check_env()?;
+  let os_name = sys_info::os_type().unwrap_or_else(|_| "".to_string());
+  Ok(JsonOp::Sync(json!(os_name)))
+}
diff --git a/cli/tests/unit/os_test.ts b/cli/tests/unit/os_test.ts
index 9698692c7..deb0385a8 100644
--- a/cli/tests/unit/os_test.ts
+++ b/cli/tests/unit/os_test.ts
@@ -326,6 +326,22 @@ unitTest({ perms: { env: false } }, function hostnamePerm(): void {
   assert(caughtError);
 });
 
+unitTest({ perms: { env: true } }, function osName(): void {
+  assertNotEquals(Deno.osName(), "");
+});
+
+unitTest({ perms: { env: false } }, function osNamePerm(): void {
+  let caughtError = false;
+  try {
+    Deno.osName();
+  } catch (err) {
+    caughtError = true;
+    assert(err instanceof Deno.errors.PermissionDenied);
+    assertEquals(err.name, "PermissionDenied");
+  }
+  assert(caughtError);
+});
+
 unitTest({ perms: { env: true } }, function releaseDir(): void {
   assertNotEquals(Deno.osRelease(), "");
 });