From 27fd2d256bc46b4acef1c631c9c9bb6d4f979025 Mon Sep 17 00:00:00 2001
From: Karishnu Poddar <karishnu@gmail.com>
Date: Wed, 8 Jul 2020 14:41:20 +0530
Subject: [PATCH] fix(eslint-plugin): [switch-exhaustiveness-check] Support non
 English characters

---
 .../src/rules/switch-exhaustiveness-check.ts  | 24 ++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/packages/eslint-plugin/src/rules/switch-exhaustiveness-check.ts b/packages/eslint-plugin/src/rules/switch-exhaustiveness-check.ts
index bf282f74d86..d8a7750efba 100644
--- a/packages/eslint-plugin/src/rules/switch-exhaustiveness-check.ts
+++ b/packages/eslint-plugin/src/rules/switch-exhaustiveness-check.ts
@@ -32,6 +32,25 @@ export default createRule({
     const sourceCode = context.getSourceCode();
     const service = getParserServices(context);
     const checker = service.program.getTypeChecker();
+    const compilerOptions = service.program.getCompilerOptions();
+
+    function requiresQuoting(name: string): boolean {
+      if (name.length === 0) {
+        return true;
+      }
+
+      if (!ts.isIdentifierStart(name.charCodeAt(0), compilerOptions.target)) {
+        return true;
+      }
+
+      for (let i = 1; i < name.length; i += 1) {
+        if (!ts.isIdentifierPart(name.charCodeAt(i), compilerOptions.target)) {
+          return true;
+        }
+      }
+
+      return false;
+    }
 
     function getNodeType(node: TSESTree.Node): ts.Type {
       const tsNode = service.esTreeNodeToTSNodeMap.get(node);
@@ -44,7 +63,6 @@ export default createRule({
       missingBranchTypes: Array<ts.Type>,
       symbolName?: string,
     ): TSESLint.RuleFix | null {
-      const identifierRegex = /^[a-zA-Z_$][0-9a-zA-Z_$]*$/;
       const lastCase =
         node.cases.length > 0 ? node.cases[node.cases.length - 1] : null;
       const caseIndent = lastCase
@@ -74,8 +92,8 @@ export default createRule({
 
         if (
           symbolName &&
-          missingBranchName &&
-          !identifierRegex.test(missingBranchName.toString())
+          (missingBranchName || missingBranchName === '') &&
+          requiresQuoting(missingBranchName.toString())
         ) {
           caseTest = `${symbolName}['${missingBranchName}']`;
         }