Eslint fixes (denoland/deno_std#356)

Make warnings fail
Original: https://github.com/denoland/deno_std/commit/4543b563a9a01c8c168aafcbfd9d4634effba7fc

2 files changed, 8 insertions, 6 deletions

diff --git a/prettier/main.ts b/prettier/main.ts
index f4a2232cc..a11501de1 100755
--- a/prettier/main.ts
+++ b/prettier/main.ts
@@ -188,7 +188,7 @@ async function checkSourceFiles(
 
   const results = await Promise.all(checks);
 
-  if (results.every(result => result)) {
+  if (results.every((result): boolean => result)) {
     console.log("Every file is formatted");
     exit(0);
   } else {
@@ -240,10 +240,12 @@ async function main(opts): Promise<void> {
   }
   const options = { flags: "g" };
   const skip = Array.isArray(ignore)
-    ? ignore.map((i: string) => glob(i, options))
+    ? ignore.map((i: string): RegExp => glob(i, options))
     : [glob(ignore, options)];
   const match =
-    args.length > 0 ? args.map((a: string) => glob(a, options)) : undefined;
+    args.length > 0
+      ? args.map((a: string): RegExp => glob(a, options))
+      : undefined;
   const files = walk(".", { match, skip });
   try {
     if (check) {
diff --git a/prettier/main_test.ts b/prettier/main_test.ts
index 3d5d54d66..0c8cca712 100644
--- a/prettier/main_test.ts
+++ b/prettier/main_test.ts
@@ -45,7 +45,7 @@ async function clearTestdataChanges(): Promise<void> {
   await xrun({ args: ["git", "checkout", testdata] }).status();
 }
 
-test(async function testPrettierCheckAndFormatFiles() {
+test(async function testPrettierCheckAndFormatFiles(): Promise<void> {
   await clearTestdataChanges();
 
   const files = [
@@ -73,7 +73,7 @@ Formatting ./prettier/testdata/1.js`
   await clearTestdataChanges();
 });
 
-test(async function testPrettierCheckAndFormatDirs() {
+test(async function testPrettierCheckAndFormatDirs(): Promise<void> {
   await clearTestdataChanges();
 
   const dirs = [join(testdata, "foo"), join(testdata, "bar")];
@@ -99,7 +99,7 @@ Formatting ./prettier/testdata/foo/1.js`
   await clearTestdataChanges();
 });
 
-test(async function testPrettierOptions() {
+test(async function testPrettierOptions(): Promise<void> {
   await clearTestdataChanges();
 
   const file0 = join(testdata, "opts", "0.ts");