From 5f453482bc98f7c10ba19d34586174ddee76b94e Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Mon, 3 Jan 2022 22:16:25 +0800
Subject: [PATCH] Add internal ESLint rule `await-cli-tests` (#12013)

Co-authored-by: Sosuke Suzuki <aosukeke@gmail.com>
---
 .eslintrc.js                                  |  6 ++
 .../await-cli-tests.js                        | 72 +++++++++++++++++++
 .../index.js                                  |  1 +
 .../test.js                                   | 26 +++++++
 4 files changed, 105 insertions(+)
 create mode 100644 scripts/tools/eslint-plugin-prettier-internal-rules/await-cli-tests.js

diff --git a/.eslintrc.js b/.eslintrc.js
index dd11a9d1e..e06620c5f 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -179,6 +179,12 @@ module.exports = {
         "jest/prefer-to-be": "error",
       },
     },
+    {
+      files: ["tests/integration/**/*.js"],
+      rules: {
+        "prettier-internal-rules/await-cli-tests": "error",
+      },
+    },
     {
       files: ["tests/**/*.js"],
       rules: {
diff --git a/scripts/tools/eslint-plugin-prettier-internal-rules/await-cli-tests.js b/scripts/tools/eslint-plugin-prettier-internal-rules/await-cli-tests.js
new file mode 100644
index 000000000..b066f1a07
--- /dev/null
+++ b/scripts/tools/eslint-plugin-prettier-internal-rules/await-cli-tests.js
@@ -0,0 +1,72 @@
+"use strict";
+
+const selector = [
+  "CallExpression",
+  '[callee.type="Identifier"]',
+  '[callee.name="runPrettier"]',
+].join("");
+
+const MESSAGE_ID_CALL = "await-cli-tests/call";
+const MESSAGE_ID_GETTER = "await-cli-tests/getter";
+
+module.exports = {
+  meta: {
+    type: "suggestion",
+    docs: {
+      url: "https://github.com/prettier/prettier/blob/main/scripts/tools/eslint-plugin-prettier-internal-rules/await-cli-tests.js",
+    },
+    messages: {
+      [MESSAGE_ID_CALL]:
+        "'runPrettier()' should be awaited or calling `.test()`.",
+      [MESSAGE_ID_GETTER]: "'runPrettier().{{property}}' should be awaited.",
+    },
+  },
+  create(context) {
+    return {
+      [selector](callExpression) {
+        const { parent } = callExpression;
+        if (
+          parent.type === "AwaitExpression" &&
+          parent.argument === callExpression
+        ) {
+          return;
+        }
+
+        if (
+          parent.type === "MemberExpression" &&
+          parent.object === callExpression &&
+          parent.property.type === "Identifier" &&
+          parent.property.name === "test" &&
+          parent.parent.type === "CallExpression" &&
+          parent.parent.callee === parent
+        ) {
+          return;
+        }
+
+        if (
+          parent.type === "MemberExpression" &&
+          parent.object === callExpression &&
+          parent.property.type === "Identifier" &&
+          ["status", "write", "stdout", "stderr"].includes(parent.property.name)
+        ) {
+          const memberExpression = callExpression.parent;
+          if (
+            memberExpression.parent.type === "AwaitExpression" &&
+            memberExpression.parent.argument === memberExpression
+          ) {
+            return;
+          }
+
+          context.report({
+            node: memberExpression.property,
+            messageId: MESSAGE_ID_GETTER,
+            data: { property: memberExpression.property.name },
+          });
+          return;
+        }
+
+        context.report({ node: callExpression, messageId: MESSAGE_ID_CALL });
+      },
+    };
+  },
+};
diff --git a/scripts/tools/eslint-plugin-prettier-internal-rules/index.js b/scripts/tools/eslint-plugin-prettier-internal-rules/index.js
index 114c4cfa0..b58a79e97 100644
--- a/scripts/tools/eslint-plugin-prettier-internal-rules/index.js
+++ b/scripts/tools/eslint-plugin-prettier-internal-rules/index.js
@@ -2,6 +2,7 @@
 
 module.exports = {
   rules: {
+    "await-cli-tests": require("./await-cli-tests.js"),
     "better-parent-property-check-in-needs-parens": require("./better-parent-property-check-in-needs-parens.js"),
     "consistent-negative-index-access": require("./consistent-negative-index-access.js"),
     "directly-loc-start-end": require("./directly-loc-start-end.js"),
diff --git a/scripts/tools/eslint-plugin-prettier-internal-rules/test.js b/scripts/tools/eslint-plugin-prettier-internal-rules/test.js
index e9afa6c1d..f89175aac 100644
--- a/scripts/tools/eslint-plugin-prettier-internal-rules/test.js
+++ b/scripts/tools/eslint-plugin-prettier-internal-rules/test.js
@@ -14,6 +14,32 @@ const test = (ruleId, tests) => {
   );
 };
 
+test("await-cli-tests", {
+  valid: [
+    "async () => await runPrettier()",
+    "runPrettier().test()",
+    "notRunPrettier()",
+    "async () => await runPrettier().stderr",
+    outdent`
+      async () => {
+        const originalStdout = await runPrettier("plugins/options", ["--help"]).stdout;
+      }
+    `,
+  ],
+  invalid: [
+    {
+      code: "runPrettier()",
+      errors: [
+        { message: "'runPrettier()' should be awaited or calling `.test()`." },
+      ],
+    },
+    {
+      code: "runPrettier().stderr",
+      errors: [{ message: "'runPrettier().stderr' should be awaited." }],
+    },
+  ],
+});
+
 test("better-parent-property-check-in-needs-parens", {
   valid: ["function needsParens() {return parent.test === node;}"],
   invalid: [