From f6b96ce623cfd406287a0825b0e0cc9559e3ff5a Mon Sep 17 00:00:00 2001
From: lonyele <skyrabbits1@gmail.com>
Date: Thu, 22 Aug 2019 14:08:33 +0900
Subject: [PATCH] fix: when there are multiple arguments in BlockStatement

---
 .../rules/explicit-function-return-type.ts    | 29 +++++++++----------
 .../explicit-function-return-type.test.ts     | 11 +++++++
 2 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/packages/eslint-plugin/src/rules/explicit-function-return-type.ts b/packages/eslint-plugin/src/rules/explicit-function-return-type.ts
index da3e7334b6ab..df52383a8c26 100644
--- a/packages/eslint-plugin/src/rules/explicit-function-return-type.ts
+++ b/packages/eslint-plugin/src/rules/explicit-function-return-type.ts
@@ -169,21 +169,20 @@ export default util.createRule<Options, MessageIds>({
         return false;
       }
 
-      // Check if body is a block with a single statement
-      if (
-        body.type === AST_NODE_TYPES.BlockStatement &&
-        body.body.length === 1
-      ) {
-        const [statement] = body.body;
-
-        // Check if that statement is a return statement with an argument
-        if (
-          statement.type === AST_NODE_TYPES.ReturnStatement &&
-          !!statement.argument
-        ) {
-          // If so, check that returned argument as body
-          body = statement.argument;
-        }
+      // Check if body is a block with a return statement
+      if (body.type === AST_NODE_TYPES.BlockStatement) {
+        // Check if ReturnStatement exist among body and use that argument
+        // for checking whether it is a function expression
+        body.body.some(statement => {
+          if (
+            statement.type === AST_NODE_TYPES.ReturnStatement &&
+            !!statement.argument
+          ) {
+            // If so, check that returned argument as body
+            body = statement.argument;
+            return;
+          }
+        });
       }
 
       // Check if the body being returned is a function expression
diff --git a/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts b/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
index 942ed5ea2e89..589d665dc94b 100644
--- a/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
+++ b/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
@@ -246,6 +246,17 @@ function FunctionDeclaration() {
             `,
       options: [{ allowHigherOrderFunctions: true }],
     },
+    {
+      filename: 'test.ts',
+      code: `
+const x = (arg1: string) => {
+  const tempVar1 = 'temporary value1';
+  const tempVar2 = 'temporary value2';
+  return (arg2: number): string => 'foo';
+}
+            `,
+      options: [{ allowHigherOrderFunctions: true }],
+    },
     // https://github.com/typescript-eslint/typescript-eslint/issues/679
     {
       filename: 'test.ts',