feat(rule-tester): support multipass fixes (typescript-eslint#8883)

* feat(rule-tester): support multipass fixes * docs: mention multi-pass fixes in rule tester docs * Update docs/packages/Rule_Tester.mdx Co-authored-by: Josh Goldberg ✨ <git@joshuakgoldberg.com> * Update packages/rule-tester/src/RuleTester.ts Co-authored-by: Kirk Waiblinger <kirk.waiblinger@gmail.com> * refactor: break if fixer doesn't change the code --------- Co-authored-by: Josh Goldberg ✨ <git@joshuakgoldberg.com> Co-authored-by: Kirk Waiblinger <kirk.waiblinger@gmail.com>
JoshuaKGoldberg · May 16, 2024 · 5c80828 · 5c80828
1 parent 5753fe5
commit 5c80828
Show file tree

Hide file tree

Showing 10 changed files with 603 additions and 124 deletions.
diff --git a/docs/packages/Rule_Tester.mdx b/docs/packages/Rule_Tester.mdx
@@ -75,6 +75,15 @@ ruleTester.run('my-rule', rule, {
         /* ... */
       ],
     },
+    // Multi-pass fixes can be tested using the array form of output.
+    // Note: this is unique to typescript-eslint, and doesn't exist in ESLint core.
+    {
+      code: 'const d = 1;',
+      output: ['const e = 1;', 'const f = 1;'],
+      errors: [
+        /* ... */
+      ],
+    },
 
     // suggestions can be tested via errors
     {

diff --git a/packages/eslint-plugin-internal/tests/rules/plugin-test-formatting.test.ts b/packages/eslint-plugin-internal/tests/rules/plugin-test-formatting.test.ts
@@ -206,8 +206,18 @@ const test = [
     },
     {
       code: wrap`'for (const x of y) {}'`,
-      output: wrap`\`for (const x of y) {
+      output: [
+        wrap`\`for (const x of y) {
 }\``,
+        wrap`\`
+for (const x of y) {
+}
+\``,
+        wrap`\`
+for (const x of y) {
+}
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'invalidFormatting',
@@ -217,8 +227,18 @@ const test = [
     {
       code: wrap`'for (const x of \`asdf\`) {}'`,
       // make sure it escapes the backticks
-      output: wrap`\`for (const x of \\\`asdf\\\`) {
+      output: [
+        wrap`\`for (const x of \\\`asdf\\\`) {
 }\``,
+        wrap`\`
+for (const x of \\\`asdf\\\`) {
+}
+\``,
+        wrap`\`
+for (const x of \\\`asdf\\\`) {
+}
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'invalidFormatting',
@@ -238,7 +258,7 @@ const test = [
     },
     {
       code: wrap`\`const a = '1'\``,
-      output: wrap`"const a = '1'"`,
+      output: [wrap`"const a = '1'"`, wrap`"const a = '1';"`],
       errors: [
         {
           messageId: 'singleLineQuotes',
@@ -247,7 +267,7 @@ const test = [
     },
     {
       code: wrap`\`const a = "1";\``,
-      output: wrap`'const a = "1";'`,
+      output: [wrap`'const a = "1";'`, wrap`"const a = '1';"`],
       errors: [
         {
           messageId: 'singleLineQuotes',
@@ -258,9 +278,14 @@ const test = [
     {
       code: wrap`\`const a = "1";
 ${PARENT_INDENT}\``,
-      output: wrap`\`
+      output: [
+        wrap`\`
 const a = "1";
 ${PARENT_INDENT}\``,
+        wrap`\`
+const a = '1';
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'templateLiteralEmptyEnds',
@@ -270,9 +295,17 @@ ${PARENT_INDENT}\``,
     {
       code: wrap`\`
 ${CODE_INDENT}const a = "1";\``,
-      output: wrap`\`
+      output: [
+        wrap`\`
 ${CODE_INDENT}const a = "1";
 \``,
+        wrap`\`
+${CODE_INDENT}const a = "1";
+${PARENT_INDENT}\``,
+        wrap`\`
+${CODE_INDENT}const a = '1';
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'templateLiteralEmptyEnds',
@@ -282,10 +315,20 @@ ${CODE_INDENT}const a = "1";
     {
       code: wrap`\`const a = "1";
 ${CODE_INDENT}const b = "2";\``,
-      output: wrap`\`
+      output: [
+        wrap`\`
 const a = "1";
 ${CODE_INDENT}const b = "2";
 \``,
+        wrap`\`
+const a = "1";
+${CODE_INDENT}const b = "2";
+${PARENT_INDENT}\``,
+        wrap`\`
+const a = '1';
+const b = '2';
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'templateLiteralEmptyEnds',
@@ -297,9 +340,14 @@ ${CODE_INDENT}const b = "2";
       code: wrap`\`
 ${CODE_INDENT}const a = "1";
 \``,
-      output: wrap`\`
+      output: [
+        wrap`\`
 ${CODE_INDENT}const a = "1";
 ${PARENT_INDENT}\``,
+        wrap`\`
+${CODE_INDENT}const a = '1';
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'templateLiteralLastLineIndent',
@@ -310,9 +358,14 @@ ${PARENT_INDENT}\``,
       code: wrap`\`
 ${CODE_INDENT}const a = "1";
                       \``,
-      output: wrap`\`
+      output: [
+        wrap`\`
 ${CODE_INDENT}const a = "1";
 ${PARENT_INDENT}\``,
+        wrap`\`
+${CODE_INDENT}const a = '1';
+${PARENT_INDENT}\``,
+      ],
       errors: [
         {
           messageId: 'templateLiteralLastLineIndent',
@@ -483,7 +536,8 @@ ruleTester.run({
   ],
 });
       `,
-      output: `
+      output: [
+        `
 ruleTester.run({
   valid: [
     {
@@ -517,6 +571,75 @@ foo
   ],
 });
       `,
+        `
+ruleTester.run({
+  valid: [
+    {
+      code: 'foo;',
+    },
+    {
+      code: \`
+foo
+      \`,
+    },
+    {
+      code: \`
+      foo
+      \`,
+    },
+  ],
+  invalid: [
+    {
+      code: 'foo;',
+    },
+    {
+      code: \`
+foo
+      \`,
+    },
+    {
+      code: \`
+      foo
+      \`,
+    },
+  ],
+});
+      `,
+        `
+ruleTester.run({
+  valid: [
+    {
+      code: 'foo;',
+    },
+    {
+      code: \`
+foo;
+      \`,
+    },
+    {
+      code: \`
+      foo
+      \`,
+    },
+  ],
+  invalid: [
+    {
+      code: 'foo;',
+    },
+    {
+      code: \`
+foo;
+      \`,
+    },
+    {
+      code: \`
+      foo
+      \`,
+    },
+  ],
+});
+      `,
+      ],
       errors: [
         {
           messageId: 'singleLineQuotes',

diff --git a/packages/eslint-plugin/tests/RuleTester.ts b/packages/eslint-plugin/tests/RuleTester.ts
@@ -44,7 +44,11 @@ export function batchedSingleLineTests<
   MessageIds extends string,
   Options extends readonly unknown[],
 >(
-  options: InvalidTestCase<MessageIds, Options> | ValidTestCase<Options>,
+  options:
+    | (Omit<InvalidTestCase<MessageIds, Options>, 'output'> & {
+        output?: string | null;
+      })
+    | ValidTestCase<Options>,
 ): (InvalidTestCase<MessageIds, Options> | ValidTestCase<Options>)[] {
   // -- eslint counts lines from 1
   const lineOffset = options.code.startsWith('\n') ? 2 : 1;

diff --git a/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts b/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts
@@ -409,11 +409,16 @@ declare const nested: string, interpolation: string;
   \`le\${  \`ss\`  }\`
 }\`;
       `,
-      output: `
+      output: [
+        `
 \`use\${
   \`less\`
 }\`;
       `,
+        `
+\`useless\`;
+      `,
+      ],
       errors: [
         {
           messageId: 'noUselessTemplateLiteral',