Add test to confirm prettier . work with plugins (#8835)

tests_config/prettier-plugins/prettier-plugin-uppercase-rocks/main.js

@@ -7,6 +7,7 @@ module.exports = {
     {
       name,
       parsers: [name],
+      extensions: [`.${name}`],
     },
   ],
   parsers: {

tests_integration/__tests__/__snapshots__/patterns-dirs.js.snap

@@ -148,3 +148,20 @@ exports[`Negative patterns with explicit files: prettier dir1/a1.js dir2/a2.js '
 "dir2/a2.js
 "
 `;
+
+exports[`plugins \`*\` (stderr) 1`] = `
+"[error] No parser could be inferred for file: unknown.unknown
+"
+`;
+
+exports[`plugins \`*\` (stdout) 1`] = `
+"javascript.js
+plugin.uppercase-rocks
+"
+`;
+
+exports[`plugins \`.\` (stdout) 1`] = `
+"javascript.js
+plugin.uppercase-rocks
+"
+`;

tests_integration/__tests__/patterns-dirs.js

@@ -3,6 +3,7 @@
 const path = require("path");
 const fs = require("fs");
 const runPrettier = require("../runPrettier");
+const { projectRoot } = require("../env");
 
 expect.addSnapshotSerializer(require("../path-serializer"));
 
@@ -58,6 +59,34 @@ testPatterns("Exclude yarn.lock when expanding directories", ["."], {
   stdout: expect.not.stringContaining("yarn.lock"),
 });
 
+const uppercaseRocksPlugin = path.join(
+  projectRoot,
+  "tests_config/prettier-plugins/prettier-plugin-uppercase-rocks"
+);
+describe("plugins `.`", () => {
+  runPrettier("cli/dirs/plugins", [
+    ".",
+    "-l",
+    "--plugin",
+    uppercaseRocksPlugin,
+  ]).test({
+    write: [],
+    stderr: "",
+    status: 1,
+  });
+});
+describe("plugins `*`", () => {
+  runPrettier("cli/dirs/plugins", [
+    "*",
+    "-l",
+    "--plugin",
+    uppercaseRocksPlugin,
+  ]).test({
+    write: [],
+    status: 1,
+  });
+});
+
 if (path.sep === "/") {
   // Don't use snapshots in these tests as they're conditionally executed on non-Windows only.
 

tests_integration/cli/dirs/plugins/javascript.js

@@ -0,0 +1 @@
+const foo =              'bar'

tests_integration/cli/dirs/plugins/plugin.uppercase-rocks

@@ -0,0 +1 @@
+PrEtTiEr

tests_integration/env.js

@@ -15,7 +15,10 @@ const thirdParty = isProduction
   ? path.join(prettierRootDir, "./third-party")
   : path.join(prettierRootDir, "./src/common/third-party");
 
+const projectRoot = path.join(__dirname, "..");
+
 module.exports = {
   thirdParty,
   prettierCli,
+  projectRoot,
 };