fix(eslint-plugin): [restrict-plus-operands] consider template litera…

…l types as strings (#3234)
typescript-eslint · Apr 5, 2021 · ccfd68e · ccfd68e
1 parent 0913f40
commit ccfd68e
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Showing 2 changed files with 10 additions and 1 deletion.
diff --git a/packages/eslint-plugin/src/rules/restrict-plus-operands.ts b/packages/eslint-plugin/src/rules/restrict-plus-operands.ts
@@ -57,7 +57,10 @@ export default util.createRule<Options, MessageIds>({
       if (type.isNumberLiteral()) {
         return 'number';
       }
-      if (type.isStringLiteral()) {
+      if (
+        type.isStringLiteral() ||
+        util.isTypeFlagSet(type, ts.TypeFlags.TemplateLiteral)
+      ) {
         return 'string';
       }
       // is BigIntLiteral

diff --git a/packages/eslint-plugin/tests/rules/restrict-plus-operands.test.ts b/packages/eslint-plugin/tests/rules/restrict-plus-operands.test.ts
@@ -110,6 +110,12 @@ const x = a + b;
 declare const a: 'string literal' & string;
 declare const b: string;
 const x = a + b;
+    `,
+    `
+function A(s: string) {
+  return \`a\${s}b\` as const;
+}
+const b = A('') + '!';
     `,
     {
       code: `