feat(eslint-plugin): [no-useless-template-literals] add fix suggestio…

…ns (#8065) * feat(eslint-plugin): [no-useless-template-literals] add fix suggestions * change message * add quasis to cspell * add some test cases * use fix instead of suggestion
typescript-eslint · Jan 9, 2024 · c3767ed · c3767ed
1 parent 8ca5e5e
commit c3767ed
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Showing 3 changed files with 244 additions and 14 deletions.
diff --git a/.cspell.json b/.cspell.json
@@ -107,6 +107,7 @@
     "preact",
     "Premade",
     "prettier's",
+    "quasis",
     "Quickstart",
     "recurse",
     "redeclaration",

diff --git a/packages/eslint-plugin/src/rules/no-useless-template-literals.ts b/packages/eslint-plugin/src/rules/no-useless-template-literals.ts
@@ -1,4 +1,4 @@
-import type { TSESTree } from '@typescript-eslint/utils';
+import type { TSESLint, TSESTree } from '@typescript-eslint/utils';
 import { AST_NODE_TYPES } from '@typescript-eslint/utils';
 import * as ts from 'typescript';
 
@@ -15,7 +15,8 @@ type MessageId = 'noUselessTemplateLiteral';
 export default createRule<[], MessageId>({
   name: 'no-useless-template-literals',
   meta: {
-    type: 'problem',
+    fixable: 'code',
+    type: 'suggestion',
     docs: {
       description: 'Disallow unnecessary template literals',
       recommended: 'strict',
@@ -68,6 +69,22 @@ export default createRule<[], MessageId>({
           context.report({
             node: node.expressions[0],
             messageId: 'noUselessTemplateLiteral',
+            fix(fixer): TSESLint.RuleFix[] {
+              const [prevQuasi, nextQuasi] = node.quasis;
+
+              // Remove the quasis and backticks.
+              return [
+                fixer.removeRange([
+                  prevQuasi.range[1] - 3,
+                  node.expressions[0].range[0],
+                ]),
+
+                fixer.removeRange([
+                  node.expressions[0].range[1],
+                  nextQuasi.range[0] + 2,
+                ]),
+              ];
+            },
           });
 
           return;
@@ -83,6 +100,40 @@ export default createRule<[], MessageId>({
           context.report({
             node: expression,
             messageId: 'noUselessTemplateLiteral',
+            fix(fixer): TSESLint.RuleFix[] {
+              const index = node.expressions.indexOf(expression);
+              const prevQuasi = node.quasis[index];
+              const nextQuasi = node.quasis[index + 1];
+
+              // Remove the quasis' parts that are related to the current expression.
+              const fixes = [
+                fixer.removeRange([
+                  prevQuasi.range[1] - 2,
+                  expression.range[0],
+                ]),
+
+                fixer.removeRange([
+                  expression.range[1],
+                  nextQuasi.range[0] + 1,
+                ]),
+              ];
+
+              // Remove quotes for string literals (i.e. `'a'` will become `a`).
+              const isStringLiteral =
+                isUnderlyingTypeString(expression) &&
+                expression.type === AST_NODE_TYPES.Literal;
+
+              if (isStringLiteral) {
+                const escapedValue = expression.value.replace(
+                  /([`$\\])/g,
+                  '\\$1',
+                );
+
+                fixes.push(fixer.replaceText(expression, escapedValue));
+              }
+
+              return fixes;
+            },
           });
         });
       },