feat(eslint-plugin): [consistent-type-assertions] autofix angle bracket assertions to as (typescript-eslint#6641)

NotWoods · web-flow · commit ad8ea64dbdf0 · 2023-03-21T16:00:05.000-04:00
* Autofix angle bracket assertions to as

* Include parentheses
diff --git a/packages/eslint-plugin/src/rules/consistent-type-assertions.ts b/packages/eslint-plugin/src/rules/consistent-type-assertions.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 util from '../util';
@@ -23,6 +23,7 @@ export default util.createRule<Options, MessageIds>({
   name: 'consistent-type-assertions',
   meta: {
     type: 'suggestion',
+    fixable: 'code',
     docs: {
       description: 'Enforce consistent usage of type assertions',
       recommended: 'strict',
@@ -83,6 +84,28 @@ export default util.createRule<Options, MessageIds>({
       );
     }
 
+    function getTextWithParentheses(node: TSESTree.Node): string {
+      // Capture parentheses before and after the node
+      let beforeCount = 0;
+      let afterCount = 0;
+
+      if (util.isParenthesized(node, sourceCode)) {
+        const bodyOpeningParen = sourceCode.getTokenBefore(
+          node,
+          util.isOpeningParenToken,
+        )!;
+        const bodyClosingParen = sourceCode.getTokenAfter(
+          node,
+          util.isClosingParenToken,
+        )!;
+
+        beforeCount = node.range[0] - bodyOpeningParen.range[0];
+        afterCount = bodyClosingParen.range[1] - node.range[1];
+      }
+
+      return sourceCode.getText(node, beforeCount, afterCount);
+    }
+
     function reportIncorrectAssertionType(
       node: TSESTree.TSTypeAssertion | TSESTree.TSAsExpression,
     ): void {
@@ -100,6 +123,19 @@ export default util.createRule<Options, MessageIds>({
           messageId !== 'never'
             ? { cast: sourceCode.getText(node.typeAnnotation) }
             : {},
+        fix:
+          messageId === 'as'
+            ? (fixer): TSESLint.RuleFix[] => [
+                fixer.replaceText(
+                  node,
+                  getTextWithParentheses(node.expression),
+                ),
+                fixer.insertTextAfter(
+                  node,
+                  ` as ${getTextWithParentheses(node.typeAnnotation)}`,
+                ),
+              ]
+            : undefined,
       });
     }
 
diff --git a/packages/eslint-plugin/tests/rules/consistent-type-assertions.test.ts b/packages/eslint-plugin/tests/rules/consistent-type-assertions.test.ts
@@ -9,7 +9,12 @@ const ANGLE_BRACKET_TESTS_EXCEPT_CONST_CASE = `
 const x = <Foo>new Generic<int>();
 const x = <A>b;
 const x = <readonly number[]>[1];
-const x = <a | b>('string');`;
+const x = <a | b>('string');
+const x = <A>!'string';
+const x = <A>a + b;
+const x = <(A)>a + (b);
+const x = <Foo>(new Generic<string>());
+const x = (new (<Foo>Generic<string>)());`;
 
 const ANGLE_BRACKET_TESTS = `${ANGLE_BRACKET_TESTS_EXCEPT_CONST_CASE}
 const x = <const>{ key: 'value' };
@@ -19,7 +24,12 @@ const AS_TESTS_EXCEPT_CONST_CASE = `
 const x = new Generic<int>() as Foo;
 const x = b as A;
 const x = [1] as readonly number[];
-const x = ('string') as a | b;`;
+const x = ('string') as a | b;
+const x = !'string' as A;
+const x = a as A + b;
+const x = a as (A) + (b);
+const x = (new Generic<string>()) as Foo;
+const x = (new (Generic<string> as Foo)());`;
 
 const AS_TESTS = `${AS_TESTS_EXCEPT_CONST_CASE}
 const x = { key: 'value' } as const;
@@ -164,6 +174,26 @@ ruleTester.run('consistent-type-assertions', rule, {
           messageId: 'angle-bracket',
           line: 6,
         },
+        {
+          messageId: 'angle-bracket',
+          line: 7,
+        },
+        {
+          messageId: 'angle-bracket',
+          line: 8,
+        },
+        {
+          messageId: 'angle-bracket',
+          line: 9,
+        },
+        {
+          messageId: 'angle-bracket',
+          line: 10,
+        },
+        {
+          messageId: 'angle-bracket',
+          line: 11,
+        },
       ],
     }),
     ...batchedSingleLineTests({
@@ -194,7 +224,28 @@ ruleTester.run('consistent-type-assertions', rule, {
           messageId: 'as',
           line: 6,
         },
+        {
+          messageId: 'as',
+          line: 7,
+        },
+        {
+          messageId: 'as',
+          line: 8,
+        },
+        {
+          messageId: 'as',
+          line: 9,
+        },
+        {
+          messageId: 'as',
+          line: 10,
+        },
+        {
+          messageId: 'as',
+          line: 11,
+        },
       ],
+      output: AS_TESTS,
     }),
     ...batchedSingleLineTests({
       code: AS_TESTS_EXCEPT_CONST_CASE,
@@ -224,6 +275,22 @@ ruleTester.run('consistent-type-assertions', rule, {
           messageId: 'never',
           line: 6,
         },
+        {
+          messageId: 'never',
+          line: 7,
+        },
+        {
+          messageId: 'never',
+          line: 8,
+        },
+        {
+          messageId: 'never',
+          line: 9,
+        },
+        {
+          messageId: 'never',
+          line: 10,
+        },
       ],
     }),
     ...batchedSingleLineTests({
@@ -254,6 +321,22 @@ ruleTester.run('consistent-type-assertions', rule, {
           messageId: 'never',
           line: 6,
         },
+        {
+          messageId: 'never',
+          line: 7,
+        },
+        {
+          messageId: 'never',
+          line: 8,
+        },
+        {
+          messageId: 'never',
+          line: 9,
+        },
+        {
+          messageId: 'never',
+          line: 10,
+        },
       ],
     }),
     ...batchedSingleLineTests({
