From 9af968ff47a8f7fdde678d9d11297d400c0fe568 Mon Sep 17 00:00:00 2001
From: Azat S <to@azat.io>
Date: Sun, 13 Aug 2023 21:59:18 +0300
Subject: [PATCH 1/3] feat(rule-tester): allow to create empty tests

---
 packages/rule-tester/src/RuleTester.ts | 48 ++++++++++++++------------
 1 file changed, 26 insertions(+), 22 deletions(-)

diff --git a/packages/rule-tester/src/RuleTester.ts b/packages/rule-tester/src/RuleTester.ts
index cc6577611378..198309699af9 100644
--- a/packages/rule-tester/src/RuleTester.ts
+++ b/packages/rule-tester/src/RuleTester.ts
@@ -395,33 +395,37 @@ export class RuleTester extends TestFramework {
      * one of the templates above.
      */
     constructor.describe(ruleName, () => {
-      constructor.describe('valid', () => {
-        normalizedTests.valid.forEach(valid => {
-          const testName = ((): string => {
-            if (valid.name == null || valid.name.length === 0) {
-              return valid.code;
-            }
-            return valid.name;
-          })();
-          constructor[getTestMethod(valid)](sanitize(testName), () => {
-            this.#testValidTemplate(ruleName, rule, valid);
+      if (normalizedTests.valid.length) {
+        constructor.describe('valid', () => {
+          normalizedTests.valid.forEach(valid => {
+            const testName = ((): string => {
+              if (valid.name == null || valid.name.length === 0) {
+                return valid.code;
+              }
+              return valid.name;
+            })();
+            constructor[getTestMethod(valid)](sanitize(testName), () => {
+              this.#testValidTemplate(ruleName, rule, valid);
+            });
           });
         });
-      });
+      }
 
-      constructor.describe('invalid', () => {
-        normalizedTests.invalid.forEach(invalid => {
-          const name = ((): string => {
-            if (invalid.name == null || invalid.name.length === 0) {
-              return invalid.code;
-            }
-            return invalid.name;
-          })();
-          constructor[getTestMethod(invalid)](sanitize(name), () => {
-            this.#testInvalidTemplate(ruleName, rule, invalid);
+      if (normalizedTests.invalid.length) {
+        constructor.describe('invalid', () => {
+          normalizedTests.invalid.forEach(invalid => {
+            const name = ((): string => {
+              if (invalid.name == null || invalid.name.length === 0) {
+                return invalid.code;
+              }
+              return invalid.name;
+            })();
+            constructor[getTestMethod(invalid)](sanitize(name), () => {
+              this.#testInvalidTemplate(ruleName, rule, invalid);
+            });
           });
         });
-      });
+      }
     });
   }
 

From 2f683f8d17230079e62abf28e820622951213d80 Mon Sep 17 00:00:00 2001
From: "Azat S." <to@azat.io>
Date: Mon, 4 Sep 2023 00:55:38 +0300
Subject: [PATCH 2/3] feat(rule-tester): add tests with empty valid and invalid
 suites

---
 packages/rule-tester/tests/RuleTester.test.ts | 31 +++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/packages/rule-tester/tests/RuleTester.test.ts b/packages/rule-tester/tests/RuleTester.test.ts
index 25b6aa0888ed..47579cdd69d8 100644
--- a/packages/rule-tester/tests/RuleTester.test.ts
+++ b/packages/rule-tester/tests/RuleTester.test.ts
@@ -819,6 +819,37 @@ describe('RuleTester', () => {
         expect(mockedDescribeSkip.mock.calls).toHaveLength(0);
         // expect(mockedIt.mock.lastCall).toMatchInlineSnapshot(`undefined`);
       });
+
+      it('does not call describe with valid if no valid tests are provided', () => {
+        const ruleTester = new RuleTester();
+
+        ruleTester.run('my-rule', NOOP_RULE, {
+          valid: [],
+          invalid: [
+            {
+              code: 'invalid',
+              errors: [{ messageId: 'error' }],
+            },
+          ],
+        });
+
+        expect(mockedDescribe.mock.calls).toHaveLength(2);
+      });
+
+      it('does not call describe with invalid if no invalid tests are provided', () => {
+        const ruleTester = new RuleTester();
+
+        ruleTester.run('my-rule', NOOP_RULE, {
+          valid: [
+            {
+              code: 'valid',
+            },
+          ],
+          invalid: [],
+        });
+
+        expect(mockedDescribe.mock.calls).toHaveLength(2);
+      });
     });
   });
 });

From 50adaa0267600cf387c1351ed41ee97eb09e0ccc Mon Sep 17 00:00:00 2001
From: "Azat S." <to@azat.io>
Date: Mon, 4 Sep 2023 01:07:02 +0300
Subject: [PATCH 3/3] fix(rule-tester): improve tests with empty rule tester
 suites

---
 packages/rule-tester/tests/RuleTester.test.ts | 26 +++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/packages/rule-tester/tests/RuleTester.test.ts b/packages/rule-tester/tests/RuleTester.test.ts
index 47579cdd69d8..07ad0f31f8ab 100644
--- a/packages/rule-tester/tests/RuleTester.test.ts
+++ b/packages/rule-tester/tests/RuleTester.test.ts
@@ -833,7 +833,18 @@ describe('RuleTester', () => {
           ],
         });
 
-        expect(mockedDescribe.mock.calls).toHaveLength(2);
+        expect(mockedDescribe.mock.calls).toMatchInlineSnapshot(`
+          [
+            [
+              "my-rule",
+              [Function],
+            ],
+            [
+              "invalid",
+              [Function],
+            ],
+          ]
+        `);
       });
 
       it('does not call describe with invalid if no invalid tests are provided', () => {
@@ -848,7 +859,18 @@ describe('RuleTester', () => {
           invalid: [],
         });
 
-        expect(mockedDescribe.mock.calls).toHaveLength(2);
+        expect(mockedDescribe.mock.calls).toMatchInlineSnapshot(`
+          [
+            [
+              "my-rule",
+              [Function],
+            ],
+            [
+              "valid",
+              [Function],
+            ],
+          ]
+        `);
       });
     });
   });