Add require-await lint rule (#4401)

32 files changed, 104 insertions, 114 deletions

diff --git a/cli/js/buffer.ts b/cli/js/buffer.ts
index 91c06a202..db2bb22e4 100644
--- a/cli/js/buffer.ts
+++ b/cli/js/buffer.ts
@@ -106,7 +106,7 @@ export class Buffer implements Reader, SyncReader, Writer, SyncWriter {
     return nread;
   }
 
-  async read(p: Uint8Array): Promise<number | EOF> {
+  read(p: Uint8Array): Promise<number | EOF> {
     const rr = this.readSync(p);
     return Promise.resolve(rr);
   }
@@ -116,7 +116,7 @@ export class Buffer implements Reader, SyncReader, Writer, SyncWriter {
     return copyBytes(this.buf, p, m);
   }
 
-  async write(p: Uint8Array): Promise<number> {
+  write(p: Uint8Array): Promise<number> {
     const n = this.writeSync(p);
     return Promise.resolve(n);
   }
diff --git a/cli/js/compiler.ts b/cli/js/compiler.ts
index 914a0baf0..419f07063 100644
--- a/cli/js/compiler.ts
+++ b/cli/js/compiler.ts
@@ -302,7 +302,7 @@ async function runtimeCompile(
   }
 }
 
-async function runtimeTranspile(
+function runtimeTranspile(
   request: CompilerRequestRuntimeTranspile
 ): Promise<Record<string, TranspileOnlyResult>> {
   const result: Record<string, TranspileOnlyResult> = {};
@@ -325,7 +325,7 @@ async function runtimeTranspile(
     );
     result[fileName] = { source, map };
   }
-  return result;
+  return Promise.resolve(result);
 }
 
 async function tsCompilerOnMessage({
diff --git a/cli/js/ops/fetch.ts b/cli/js/ops/fetch.ts
index 8d6a461ab..09b9ac1ec 100644
--- a/cli/js/ops/fetch.ts
+++ b/cli/js/ops/fetch.ts
@@ -15,7 +15,7 @@ export interface FetchResponse {
   headers: Array<[string, string]>;
 }
 
-export async function fetch(
+export function fetch(
   args: FetchRequest,
   body: ArrayBufferView | undefined
 ): Promise<FetchResponse> {
diff --git a/cli/js/ops/fs/make_temp.ts b/cli/js/ops/fs/make_temp.ts
index aeab9afc7..85dea5f20 100644
--- a/cli/js/ops/fs/make_temp.ts
+++ b/cli/js/ops/fs/make_temp.ts
@@ -11,9 +11,7 @@ export function makeTempDirSync(options: MakeTempOptions = {}): string {
   return sendSync("op_make_temp_dir", options);
 }
 
-export async function makeTempDir(
-  options: MakeTempOptions = {}
-): Promise<string> {
+export function makeTempDir(options: MakeTempOptions = {}): Promise<string> {
   return sendAsync("op_make_temp_dir", options);
 }
 
@@ -21,8 +19,6 @@ export function makeTempFileSync(options: MakeTempOptions = {}): string {
   return sendSync("op_make_temp_file", options);
 }
 
-export async function makeTempFile(
-  options: MakeTempOptions = {}
-): Promise<string> {
+export function makeTempFile(options: MakeTempOptions = {}): Promise<string> {
   return sendAsync("op_make_temp_file", options);
 }
diff --git a/cli/js/ops/fs/open.ts b/cli/js/ops/fs/open.ts
index 2ac5c715c..87696935f 100644
--- a/cli/js/ops/fs/open.ts
+++ b/cli/js/ops/fs/open.ts
@@ -26,7 +26,7 @@ export function openSync(
   return sendSync("op_open", { path, options, openMode, mode });
 }
 
-export async function open(
+export function open(
   path: string,
   openMode: OpenMode | undefined,
   options: OpenOptions | undefined
diff --git a/cli/js/ops/fs/read_link.ts b/cli/js/ops/fs/read_link.ts
index 403cd6def..4ac8db3db 100644
--- a/cli/js/ops/fs/read_link.ts
+++ b/cli/js/ops/fs/read_link.ts
@@ -5,6 +5,6 @@ export function readlinkSync(path: string): string {
   return sendSync("op_read_link", { path });
 }
 
-export async function readlink(path: string): Promise<string> {
+export function readlink(path: string): Promise<string> {
   return sendAsync("op_read_link", { path });
 }
diff --git a/cli/js/ops/fs/realpath.ts b/cli/js/ops/fs/realpath.ts
index e68e32bf0..e8a904079 100644
--- a/cli/js/ops/fs/realpath.ts
+++ b/cli/js/ops/fs/realpath.ts
@@ -5,6 +5,6 @@ export function realpathSync(path: string): string {
   return sendSync("op_realpath", { path });
 }
 
-export async function realpath(path: string): Promise<string> {
+export function realpath(path: string): Promise<string> {
   return sendAsync("op_realpath", { path });
 }
diff --git a/cli/js/ops/fs/seek.ts b/cli/js/ops/fs/seek.ts
index dfac9bf63..c7e4c9172 100644
--- a/cli/js/ops/fs/seek.ts
+++ b/cli/js/ops/fs/seek.ts
@@ -10,7 +10,7 @@ export function seekSync(
   return sendSync("op_seek", { rid, offset, whence });
 }
 
-export async function seek(
+export function seek(
   rid: number,
   offset: number,
   whence: SeekMode
diff --git a/cli/js/ops/fs_events.ts b/cli/js/ops/fs_events.ts
index 706efc1b0..4c08995b8 100644
--- a/cli/js/ops/fs_events.ts
+++ b/cli/js/ops/fs_events.ts
@@ -15,15 +15,15 @@ class FsEvents implements AsyncIterableIterator<FsEvent> {
     this.rid = sendSync("op_fs_events_open", { recursive, paths });
   }
 
-  async next(): Promise<IteratorResult<FsEvent>> {
+  next(): Promise<IteratorResult<FsEvent>> {
     return sendAsync("op_fs_events_poll", {
       rid: this.rid
     });
   }
 
-  async return(value?: FsEvent): Promise<IteratorResult<FsEvent>> {
+  return(value?: FsEvent): Promise<IteratorResult<FsEvent>> {
     close(this.rid);
-    return { value, done: true };
+    return Promise.resolve({ value, done: true });
   }
 
   [Symbol.asyncIterator](): AsyncIterableIterator<FsEvent> {
diff --git a/cli/js/ops/net.ts b/cli/js/ops/net.ts
index 5a72be8c6..25f3a8322 100644
--- a/cli/js/ops/net.ts
+++ b/cli/js/ops/net.ts
@@ -31,7 +31,7 @@ interface AcceptResponse {
   };
 }
 
-export async function accept(rid: number): Promise<AcceptResponse> {
+export function accept(rid: number): Promise<AcceptResponse> {
   return sendAsync("op_accept", { rid });
 }
 
@@ -74,7 +74,7 @@ export interface ConnectRequest {
   port: number;
 }
 
-export async function connect(args: ConnectRequest): Promise<ConnectResponse> {
+export function connect(args: ConnectRequest): Promise<ConnectResponse> {
   return sendAsync("op_connect", args);
 }
 
@@ -87,7 +87,7 @@ interface ReceiveResponse {
   };
 }
 
-export async function receive(
+export function receive(
   rid: number,
   zeroCopy: Uint8Array
 ): Promise<ReceiveResponse> {
diff --git a/cli/js/ops/process.ts b/cli/js/ops/process.ts
index 845909d5d..384718cef 100644
--- a/cli/js/ops/process.ts
+++ b/cli/js/ops/process.ts
@@ -12,7 +12,7 @@ interface RunStatusResponse {
   exitSignal: number;
 }
 
-export async function runStatus(rid: number): Promise<RunStatusResponse> {
+export function runStatus(rid: number): Promise<RunStatusResponse> {
   return sendAsync("op_run_status", { rid });
 }
 
diff --git a/cli/js/ops/repl.ts b/cli/js/ops/repl.ts
index 3f40f4456..1781aa089 100644
--- a/cli/js/ops/repl.ts
+++ b/cli/js/ops/repl.ts
@@ -6,6 +6,6 @@ export function startRepl(historyFile: string): number {
   return sendSync("op_repl_start", { historyFile });
 }
 
-export async function readline(rid: number, prompt: string): Promise<string> {
+export function readline(rid: number, prompt: string): Promise<string> {
   return sendAsync("op_repl_readline", { rid, prompt });
 }
diff --git a/cli/js/ops/runtime_compiler.ts b/cli/js/ops/runtime_compiler.ts
index 035a4ef59..b46670ace 100644
--- a/cli/js/ops/runtime_compiler.ts
+++ b/cli/js/ops/runtime_compiler.ts
@@ -9,7 +9,7 @@ interface CompileRequest {
   bundle: boolean;
 }
 
-export async function compile(request: CompileRequest): Promise<string> {
+export function compile(request: CompileRequest): Promise<string> {
   return sendAsync("op_compile", request);
 }
 
@@ -18,6 +18,6 @@ interface TranspileRequest {
   options?: string;
 }
 
-export async function transpile(request: TranspileRequest): Promise<string> {
+export function transpile(request: TranspileRequest): Promise<string> {
   return sendAsync("op_transpile", request);
 }
diff --git a/cli/js/ops/signal.ts b/cli/js/ops/signal.ts
index 3c8d021a0..09c178105 100644
--- a/cli/js/ops/signal.ts
+++ b/cli/js/ops/signal.ts
@@ -5,7 +5,7 @@ export function bindSignal(signo: number): { rid: number } {
   return sendSync("op_signal_bind", { signo });
 }
 
-export async function pollSignal(rid: number): Promise<{ done: boolean }> {
+export function pollSignal(rid: number): Promise<{ done: boolean }> {
   return sendAsync("op_signal_poll", { rid });
 }
 
diff --git a/cli/js/ops/tls.ts b/cli/js/ops/tls.ts
index b52ad65bb..e52143cb0 100644
--- a/cli/js/ops/tls.ts
+++ b/cli/js/ops/tls.ts
@@ -23,7 +23,7 @@ interface ConnectTLSResponse {
   };
 }
 
-export async function connectTLS(
+export function connectTLS(
   args: ConnectTLSRequest
 ): Promise<ConnectTLSResponse> {
   return sendAsync("op_connect_tls", args);
@@ -43,7 +43,7 @@ interface AcceptTLSResponse {
   };
 }
 
-export async function acceptTLS(rid: number): Promise<AcceptTLSResponse> {
+export function acceptTLS(rid: number): Promise<AcceptTLSResponse> {
   return sendAsync("op_accept_tls", { rid });
 }
 
diff --git a/cli/js/ops/worker_host.ts b/cli/js/ops/worker_host.ts
index 1a7e671f4..0b9f81795 100644
--- a/cli/js/ops/worker_host.ts
+++ b/cli/js/ops/worker_host.ts
@@ -24,6 +24,6 @@ export function hostPostMessage(id: number, data: Uint8Array): void {
   sendSync("op_host_post_message", { id }, data);
 }
 
-export async function hostGetMessage(id: number): Promise<any> {
+export function hostGetMessage(id: number): Promise<any> {
   return sendAsync("op_host_get_message", { id });
 }
diff --git a/cli/js/permissions.ts b/cli/js/permissions.ts
index 097c5048a..8c2025319 100644
--- a/cli/js/permissions.ts
+++ b/cli/js/permissions.ts
@@ -47,19 +47,19 @@ export class PermissionStatus {
 }
 
 export class Permissions {
-  async query(desc: PermissionDescriptor): Promise<PermissionStatus> {
+  query(desc: PermissionDescriptor): Promise<PermissionStatus> {
     const state = permissionsOps.query(desc);
-    return new PermissionStatus(state);
+    return Promise.resolve(new PermissionStatus(state));
   }
 
-  async revoke(desc: PermissionDescriptor): Promise<PermissionStatus> {
+  revoke(desc: PermissionDescriptor): Promise<PermissionStatus> {
     const state = permissionsOps.revoke(desc);
-    return new PermissionStatus(state);
+    return Promise.resolve(new PermissionStatus(state));
   }
 
-  async request(desc: PermissionDescriptor): Promise<PermissionStatus> {
+  request(desc: PermissionDescriptor): Promise<PermissionStatus> {
     const state = permissionsOps.request(desc);
-    return new PermissionStatus(state);
+    return Promise.resolve(new PermissionStatus(state));
   }
 }
 
diff --git a/cli/js/process.ts b/cli/js/process.ts
index 991133047..ded1458a2 100644
--- a/cli/js/process.ts
+++ b/cli/js/process.ts
@@ -55,7 +55,7 @@ export class Process {
     }
   }
 
-  async status(): Promise<ProcessStatus> {
+  status(): Promise<ProcessStatus> {
     return runStatus(this.rid);
   }
 
diff --git a/cli/js/testing.ts b/cli/js/testing.ts
index 08bb2db87..22e719719 100644
--- a/cli/js/testing.ts
+++ b/cli/js/testing.ts
@@ -289,7 +289,7 @@ export class ConsoleTestReporter implements TestReporter {
     this.encoder = new TextEncoder();
   }
 
-  private log(msg: string, noNewLine = false): void {
+  private log(msg: string, noNewLine = false): Promise<void> {
     if (!noNewLine) {
       msg += "\n";
     }
@@ -298,19 +298,22 @@ export class ConsoleTestReporter implements TestReporter {
     // compared to `console.log`; `core.print` on the other hand
     // is line-buffered and doesn't output message without newline
     stdout.writeSync(this.encoder.encode(msg));
+    return Promise.resolve();
   }
 
-  async start(event: TestEventStart): Promise<void> {
+  start(event: TestEventStart): Promise<void> {
     this.log(`running ${event.tests} tests`);
+    return Promise.resolve();
   }
 
-  async testStart(event: TestEventTestStart): Promise<void> {
+  testStart(event: TestEventTestStart): Promise<void> {
     const { name } = event;
 
     this.log(`test ${name} ... `, true);
+    return Promise.resolve();
   }
 
-  async testEnd(event: TestEventTestEnd): Promise<void> {
+  testEnd(event: TestEventTestEnd): Promise<void> {
     const { result } = event;
 
     switch (result.status) {
@@ -324,9 +327,11 @@ export class ConsoleTestReporter implements TestReporter {
         this.log(`${YELLOW_IGNORED} ${formatDuration(result.duration)}`);
         break;
     }
+
+    return Promise.resolve();
   }
 
-  async end(event: TestEventEnd): Promise<void> {
+  end(event: TestEventEnd): Promise<void> {
     const { stats, duration, results } = event;
     // Attempting to match the output of Rust's test runner.
     const failedTests = results.filter(r => r.error);
@@ -354,6 +359,8 @@ export class ConsoleTestReporter implements TestReporter {
         `${stats.filtered} filtered out ` +
         `${formatDuration(duration)}\n`
     );
+
+    return Promise.resolve();
   }
 }
 
diff --git a/cli/js/tests/dispatch_json_test.ts b/cli/js/tests/dispatch_json_test.ts
index a2306dda8..4e95b86a2 100644
--- a/cli/js/tests/dispatch_json_test.ts
+++ b/cli/js/tests/dispatch_json_test.ts
@@ -19,7 +19,7 @@ unitTest(
   }
 );
 
-unitTest(async function malformedJsonControlBuffer(): Promise<void> {
+unitTest(function malformedJsonControlBuffer(): void {
   // @ts-ignore
   const opId = Deno.core.ops()["op_open"];
   // @ts-ignore
diff --git a/cli/js/tests/dispatch_minimal_test.ts b/cli/js/tests/dispatch_minimal_test.ts
index 724a41698..60bb620db 100644
--- a/cli/js/tests/dispatch_minimal_test.ts
+++ b/cli/js/tests/dispatch_minimal_test.ts
@@ -25,7 +25,7 @@ unitTest(async function sendAsyncStackTrace(): Promise<void> {
   }
 });
 
-unitTest(async function malformedMinimalControlBuffer(): Promise<void> {
+unitTest(function malformedMinimalControlBuffer(): void {
   // @ts-ignore
   const readOpId = Deno.core.ops()["op_read"];
   // @ts-ignore
diff --git a/cli/js/tests/event_target_test.ts b/cli/js/tests/event_target_test.ts
index 09d47f704..020db1acd 100644
--- a/cli/js/tests/event_target_test.ts
+++ b/cli/js/tests/event_target_test.ts
@@ -185,7 +185,7 @@ unitTest(function eventTargetShouldAcceptAsyncFunction(): void {
   const event = new Event("foo", { bubbles: true, cancelable: false });
   let callCount = 0;
 
-  const listener = async (e: Event): Promise<void> => {
+  const listener = (e: Event): void => {
     assertEquals(e, event);
     ++callCount;
   };
@@ -210,7 +210,7 @@ unitTest(
     let callCount = 0;
 
     const listener = {
-      async handleEvent(e: Event): Promise<void> {
+      handleEvent(e: Event): void {
         assertEquals(e, event);
         ++callCount;
       }
diff --git a/cli/js/tests/files_test.ts b/cli/js/tests/files_test.ts
index b087d7398..39af460b8 100644
--- a/cli/js/tests/files_test.ts
+++ b/cli/js/tests/files_test.ts
@@ -51,16 +51,16 @@ unitTest(async function readerToAsyncIterator(): Promise<void> {
 
     constructor(private readonly s: string) {}
 
-    async read(p: Uint8Array): Promise<number | Deno.EOF> {
+    read(p: Uint8Array): Promise<number | Deno.EOF> {
       const n = Math.min(p.byteLength, this.buf.byteLength - this.offset);
       p.set(this.buf.slice(this.offset, this.offset + n));
       this.offset += n;
 
       if (n === 0) {
-        return Deno.EOF;
+        return Promise.resolve(Deno.EOF);
       }
 
-      return n;
+      return Promise.resolve(n);
     }
   }
 
diff --git a/cli/js/tests/process_test.ts b/cli/js/tests/process_test.ts
index 77c3065eb..e2da6cab5 100644
--- a/cli/js/tests/process_test.ts
+++ b/cli/js/tests/process_test.ts
@@ -359,9 +359,7 @@ if (Deno.build.os !== "win") {
     p.close();
   });
 
-  unitTest({ perms: { run: true } }, async function killFailed(): Promise<
-    void
-  > {
+  unitTest({ perms: { run: true } }, function killFailed(): void {
     const p = run({
       args: ["python", "-c", "from time import sleep; sleep(10000)"]
     });
diff --git a/cli/js/tests/read_link_test.ts b/cli/js/tests/read_link_test.ts
index 409f37110..156b31070 100644
--- a/cli/js/tests/read_link_test.ts
+++ b/cli/js/tests/read_link_test.ts
@@ -18,9 +18,7 @@ unitTest(
   }
 );
 
-unitTest({ perms: { read: false } }, async function readlinkSyncPerm(): Promise<
-  void
-> {
+unitTest({ perms: { read: false } }, function readlinkSyncPerm(): void {
   let caughtError = false;
   try {
     Deno.readlinkSync("/symlink");
diff --git a/cli/js/tests/signal_test.ts b/cli/js/tests/signal_test.ts
index e4339e290..c966e696b 100644
--- a/cli/js/tests/signal_test.ts
+++ b/cli/js/tests/signal_test.ts
@@ -15,7 +15,7 @@ function defer(n: number): Promise<void> {
 
 unitTest(
   { ignore: Deno.build.os !== "win" },
-  async function signalsNotImplemented(): Promise<void> {
+  function signalsNotImplemented(): void {
     assertThrows(
       () => {
         Deno.signal(1);
@@ -162,7 +162,7 @@ unitTest(
 
 unitTest(
   { ignore: Deno.build.os === "win", perms: { run: true } },
-  async function signalShorthandsTest(): Promise<void> {
+  function signalShorthandsTest(): void {
     let s: Deno.SignalStream;
     s = Deno.signals.alarm(); // for SIGALRM
     assert(s instanceof Deno.SignalStream);
diff --git a/cli/js/tests/stat_test.ts b/cli/js/tests/stat_test.ts
index e51204b6e..78582900e 100644
--- a/cli/js/tests/stat_test.ts
+++ b/cli/js/tests/stat_test.ts
@@ -3,9 +3,7 @@ import { unitTest, assert, assertEquals } from "./test_util.ts";
 
 // TODO Add tests for modified, accessed, and created fields once there is a way
 // to create temp files.
-unitTest({ perms: { read: true } }, async function statSyncSuccess(): Promise<
-  void
-> {
+unitTest({ perms: { read: true } }, function statSyncSuccess(): void {
   const packageInfo = Deno.statSync("README.md");
   assert(packageInfo.isFile());
   assert(!packageInfo.isSymlink());
@@ -19,9 +17,7 @@ unitTest({ perms: { read: true } }, async function statSyncSuccess(): Promise<
   assert(!testsInfo.isSymlink());
 });
 
-unitTest({ perms: { read: false } }, async function statSyncPerm(): Promise<
-  void
-> {
+unitTest({ perms: { read: false } }, function statSyncPerm(): void {
   let caughtError = false;
   try {
     Deno.statSync("README.md");
@@ -32,9 +28,7 @@ unitTest({ perms: { read: false } }, async function statSyncPerm(): Promise<
   assert(caughtError);
 });
 
-unitTest({ perms: { read: true } }, async function statSyncNotFound(): Promise<
-  void
-> {
+unitTest({ perms: { read: true } }, function statSyncNotFound(): void {
   let caughtError = false;
   let badInfo;
 
@@ -49,9 +43,7 @@ unitTest({ perms: { read: true } }, async function statSyncNotFound(): Promise<
   assertEquals(badInfo, undefined);
 });
 
-unitTest({ perms: { read: true } }, async function lstatSyncSuccess(): Promise<
-  void
-> {
+unitTest({ perms: { read: true } }, function lstatSyncSuccess(): void {
   const packageInfo = Deno.lstatSync("README.md");
   assert(packageInfo.isFile());
   assert(!packageInfo.isSymlink());
@@ -65,9 +57,7 @@ unitTest({ perms: { read: true } }, async function lstatSyncSuccess(): Promise<
   assert(!coreInfo.isSymlink());
 });
 
-unitTest({ perms: { read: false } }, async function lstatSyncPerm(): Promise<
-  void
-> {
+unitTest({ perms: { read: false } }, function lstatSyncPerm(): void {
   let caughtError = false;
   try {
     Deno.lstatSync("README.md");
@@ -78,9 +68,7 @@ unitTest({ perms: { read: false } }, async function lstatSyncPerm(): Promise<
   assert(caughtError);
 });
 
-unitTest({ perms: { read: true } }, async function lstatSyncNotFound(): Promise<
-  void
-> {
+unitTest({ perms: { read: true } }, function lstatSyncNotFound(): void {
   let caughtError = false;
   let badInfo;
 
@@ -185,7 +173,7 @@ unitTest({ perms: { read: true } }, async function lstatNotFound(): Promise<
 
 unitTest(
   { ignore: Deno.build.os !== "win", perms: { read: true, write: true } },
-  async function statNoUnixFields(): Promise<void> {
+  function statNoUnixFields(): void {
     const enc = new TextEncoder();
     const data = enc.encode("Hello");
     const tempDir = Deno.makeTempDirSync();
@@ -206,7 +194,7 @@ unitTest(
 
 unitTest(
   { ignore: Deno.build.os === "win", perms: { read: true, write: true } },
-  async function statUnixFields(): Promise<void> {
+  function statUnixFields(): void {
     const enc = new TextEncoder();
     const data = enc.encode("Hello");
     const tempDir = Deno.makeTempDirSync();
diff --git a/cli/js/tests/test_util.ts b/cli/js/tests/test_util.ts
index 42301cf72..980d32bac 100644
--- a/cli/js/tests/test_util.ts
+++ b/cli/js/tests/test_util.ts
@@ -328,7 +328,7 @@ unitTest(function permissionsMatches(): void {
  */
 unitTest(
   { perms: { read: true } },
-  async function assertAllUnitTestFilesImported(): Promise<void> {
+  function assertAllUnitTestFilesImported(): void {
     const directoryTestFiles = Deno.readdirSync("./cli/js/tests/")
       .map(k => k.name)
       .filter(
diff --git a/cli/js/tests/timers_test.ts b/cli/js/tests/timers_test.ts
index 077e27ae6..b7da6a847 100644
--- a/cli/js/tests/timers_test.ts
+++ b/cli/js/tests/timers_test.ts
@@ -27,7 +27,7 @@ function deferred(): {
   };
 }
 
-async function waitForMs(ms: number): Promise<number> {
+function waitForMs(ms: number): Promise<number> {
   return new Promise((resolve: () => void): number => setTimeout(resolve, ms));
 }
 
@@ -158,7 +158,7 @@ unitTest(async function intervalOrdering(): Promise<void> {
   assertEquals(timeouts, 1);
 });
 
-unitTest(async function intervalCancelInvalidSilentFail(): Promise<void> {
+unitTest(function intervalCancelInvalidSilentFail(): void {
   // Should silently fail (no panic)
   clearInterval(2147483647);
 });
@@ -234,7 +234,7 @@ unitTest(async function timeoutBindThis(): Promise<void> {
   }
 });
 
-unitTest(async function clearTimeoutShouldConvertToNumber(): Promise<void> {
+unitTest(function clearTimeoutShouldConvertToNumber(): void {
   let called = false;
   const obj = {
     valueOf(): number {
diff --git a/cli/js/tests/tls_test.ts b/cli/js/tests/tls_test.ts
index b405a94dd..20dd62f9b 100644
--- a/cli/js/tests/tls_test.ts
+++ b/cli/js/tests/tls_test.ts
@@ -39,7 +39,7 @@ unitTest(async function connectTLSCertFileNoReadPerm(): Promise<void> {
 
 unitTest(
   { perms: { read: true, net: true } },
-  async function listenTLSNonExistentCertKeyFiles(): Promise<void> {
+  function listenTLSNonExistentCertKeyFiles(): void {
     let err;
     const options = {
       hostname: "localhost",
@@ -70,30 +70,27 @@ unitTest(
   }
 );
 
-unitTest(
-  { perms: { net: true } },
-  async function listenTLSNoReadPerm(): Promise<void> {
-    let err;
-    try {
-      Deno.listenTLS({
-        hostname: "localhost",
-        port: 4500,
-        certFile: "cli/tests/tls/localhost.crt",
-        keyFile: "cli/tests/tls/localhost.key"
-      });
-    } catch (e) {
-      err = e;
-    }
-    assert(err instanceof Deno.errors.PermissionDenied);
-    assertEquals(err.name, "PermissionDenied");
+unitTest({ perms: { net: true } }, function listenTLSNoReadPerm(): void {
+  let err;
+  try {
+    Deno.listenTLS({
+      hostname: "localhost",
+      port: 4500,
+      certFile: "cli/tests/tls/localhost.crt",
+      keyFile: "cli/tests/tls/localhost.key"
+    });
+  } catch (e) {
+    err = e;
   }
-);
+  assert(err instanceof Deno.errors.PermissionDenied);
+  assertEquals(err.name, "PermissionDenied");
+});
 
 unitTest(
   {
     perms: { read: true, write: true, net: true }
   },
-  async function listenTLSEmptyKeyFile(): Promise<void> {
+  function listenTLSEmptyKeyFile(): void {
     let err;
     const options = {
       hostname: "localhost",
@@ -122,7 +119,7 @@ unitTest(
 
 unitTest(
   { perms: { read: true, write: true, net: true } },
-  async function listenTLSEmptyCertFile(): Promise<void> {
+  function listenTLSEmptyCertFile(): void {
     let err;
     const options = {
       hostname: "localhost",
diff --git a/cli/js/web/body.ts b/cli/js/web/body.ts
index ed21fa0ec..03c35848a 100644
--- a/cli/js/web/body.ts
+++ b/cli/js/web/body.ts
@@ -306,7 +306,7 @@ export class Body implements domTypes.Body {
     return JSON.parse(raw);
   }
 
-  public async arrayBuffer(): Promise<ArrayBuffer> {
+  public arrayBuffer(): Promise<ArrayBuffer> {
     if (
       this._bodySource instanceof Int8Array ||
       this._bodySource instanceof Int16Array ||
@@ -318,20 +318,24 @@ export class Body implements domTypes.Body {
       this._bodySource instanceof Float32Array ||
       this._bodySource instanceof Float64Array
     ) {
-      return this._bodySource.buffer as ArrayBuffer;
+      return Promise.resolve(this._bodySource.buffer as ArrayBuffer);
     } else if (this._bodySource instanceof ArrayBuffer) {
-      return this._bodySource;
+      return Promise.resolve(this._bodySource);
     } else if (typeof this._bodySource === "string") {
       const enc = new TextEncoder();
-      return enc.encode(this._bodySource).buffer as ArrayBuffer;
+      return Promise.resolve(
+        enc.encode(this._bodySource).buffer as ArrayBuffer
+      );
     } else if (this._bodySource instanceof ReadableStream) {
       // @ts-ignore
       return bufferFromStream(this._bodySource.getReader());
     } else if (this._bodySource instanceof FormData) {
       const enc = new TextEncoder();
-      return enc.encode(this._bodySource.toString()).buffer as ArrayBuffer;
+      return Promise.resolve(
+        enc.encode(this._bodySource.toString()).buffer as ArrayBuffer
+      );
     } else if (!this._bodySource) {
-      return new ArrayBuffer(0);
+      return Promise.resolve(new ArrayBuffer(0));
     }
     throw new Error(
       `Body type not yet implemented: ${this._bodySource.constructor.name}`
diff --git a/cli/js/web/fetch.ts b/cli/js/web/fetch.ts
index 7ab68d2e4..62e5d7928 100644
--- a/cli/js/web/fetch.ts
+++ b/cli/js/web/fetch.ts
@@ -60,6 +60,7 @@ class Body implements domTypes.Body, domTypes.ReadableStream, io.ReadCloser {
     return this._data;
   }
 
+  // eslint-disable-next-line require-await
   async arrayBuffer(): Promise<ArrayBuffer> {
     // If we've already bufferred the response, just return it.
     if (this._data != null) {
@@ -223,11 +224,12 @@ class Body implements domTypes.Body, domTypes.ReadableStream, io.ReadCloser {
     return read(this.rid, p);
   }
 
-  close(): void {
+  close(): Promise<void> {
     close(this.rid);
+    return Promise.resolve();
   }
 
-  async cancel(): Promise<void> {
+  cancel(): Promise<void> {
     return notImplemented();
   }
 
@@ -346,7 +348,7 @@ export class Response implements domTypes.Response {
     return false;
   }
 
-  async arrayBuffer(): Promise<ArrayBuffer> {
+  arrayBuffer(): Promise<ArrayBuffer> {
     /* You have to do the null check here and not in the function because
      * otherwise TS complains about this.body potentially being null */
     if (this.bodyViewable() || this.body == null) {
@@ -355,14 +357,14 @@ export class Response implements domTypes.Response {
     return this.body.arrayBuffer();
   }
 
-  async blob(): Promise<domTypes.Blob> {
+  blob(): Promise<domTypes.Blob> {
     if (this.bodyViewable() || this.body == null) {
       return Promise.reject(new Error("Response body is null"));
     }
     return this.body.blob();
   }
 
-  async formData(): Promise<domTypes.FormData> {
+  formData(): Promise<domTypes.FormData> {
     if (this.bodyViewable() || this.body == null) {
       return Promise.reject(new Error("Response body is null"));
     }
@@ -370,14 +372,14 @@ export class Response implements domTypes.Response {
   }
 
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  async json(): Promise<any> {
+  json(): Promise<any> {
     if (this.bodyViewable() || this.body == null) {
       return Promise.reject(new Error("Response body is null"));
     }
     return this.body.json();
   }
 
-  async text(): Promise<string> {
+  text(): Promise<string> {
     if (this.bodyViewable() || this.body == null) {
       return Promise.reject(new Error("Response body is null"));
     }
@@ -437,7 +439,7 @@ export class Response implements domTypes.Response {
   }
 }
 
-async function sendFetchReq(
+function sendFetchReq(
   url: string,
   method: string | null,
   headers: domTypes.Headers | null,