From f46d1a29c2fa04a76f930ef1b31d4941f4b863e7 Mon Sep 17 00:00:00 2001
From: FUJI Goro <gfuji@cpan.org>
Date: Mon, 22 Mar 2021 09:30:59 +0900
Subject: [PATCH] importsNotUsedAsValues: error; the most strict way to control
 imports

---
 src/Encoder.ts                 | 2 +-
 src/decode.ts                  | 4 ++--
 src/encode.ts                  | 4 ++--
 test/decode-max-length.test.ts | 2 +-
 tsconfig.json                  | 1 +
 5 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/Encoder.ts b/src/Encoder.ts
index 3cd6ebd8..38893798 100644
--- a/src/Encoder.ts
+++ b/src/Encoder.ts
@@ -2,7 +2,7 @@ import { utf8EncodeJs, utf8Count, TEXT_ENCODER_THRESHOLD, utf8EncodeTE } from ".
 import { ExtensionCodec, ExtensionCodecType } from "./ExtensionCodec";
 import { setInt64, setUint64 } from "./utils/int";
 import { ensureUint8Array } from "./utils/typedArrays";
-import { ExtData } from "./ExtData";
+import type { ExtData } from "./ExtData";
 
 export const DEFAULT_MAX_DEPTH = 100;
 export const DEFAULT_INITIAL_BUFFER_SIZE = 2048;
diff --git a/src/decode.ts b/src/decode.ts
index 727aa4a8..413b85d0 100644
--- a/src/decode.ts
+++ b/src/decode.ts
@@ -1,6 +1,6 @@
-import { ExtensionCodecType } from "./ExtensionCodec";
 import { Decoder } from "./Decoder";
-import { ContextOf, SplitUndefined } from "./context";
+import type { ExtensionCodecType } from "./ExtensionCodec";
+import type { ContextOf, SplitUndefined } from "./context";
 
 export type DecodeOptions<ContextType = undefined> = Readonly<
   Partial<{
diff --git a/src/encode.ts b/src/encode.ts
index 1fc01c78..6cb1735a 100644
--- a/src/encode.ts
+++ b/src/encode.ts
@@ -1,6 +1,6 @@
-import { ExtensionCodecType } from "./ExtensionCodec";
 import { Encoder } from "./Encoder";
-import { ContextOf, SplitUndefined } from "./context";
+import type { ExtensionCodecType } from "./ExtensionCodec";
+import type { ContextOf, SplitUndefined } from "./context";
 
 export type EncodeOptions<ContextType = undefined> = Partial<
   Readonly<{
diff --git a/test/decode-max-length.test.ts b/test/decode-max-length.test.ts
index d3b6a460..f3774eef 100644
--- a/test/decode-max-length.test.ts
+++ b/test/decode-max-length.test.ts
@@ -1,6 +1,6 @@
 import assert from "assert";
 import { encode, decode, decodeAsync } from "../src";
-import { DecodeOptions } from "../src/decode";
+import type { DecodeOptions } from "../src/decode";
 
 describe("decode with max${Type}Length specified", () => {
   async function* createStream<T>(input: T) {
diff --git a/tsconfig.json b/tsconfig.json
index 525ffa55..77d0289d 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -39,6 +39,7 @@
     "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */
     "noUncheckedIndexedAccess": true,
     "noPropertyAccessFromIndexSignature": true,
+    "importsNotUsedAsValues": "error",
 
     /* Module Resolution Options */
     "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */