Add pattern-matching test cases for formatter-template.

Author: DavidAnson

test/formatter-template/.markdownlint-cli2.jsonc

@@ -0,0 +1,14 @@
+{
+  "outputFormatters": [
+    [ "../../formatter-template", { "template": "${invalid}" } ],
+    [ "../../formatter-template", { "template": "${fileName}" } ],
+    [ "../../formatter-template", { "template": "${fileName}${fileName}${fileName}" } ],
+    [ "../../formatter-template", { "template": "${fileName:text{text}text}" } ],
+    [ "../../formatter-template", { "template": "${fileName:text{text}" } ],
+    [ "../../formatter-template", { "template": "${fileName:text}text}" } ],
+    [ "../../formatter-template", { "template": "${fileName:text${invalid}text}" } ],
+    [ "../../formatter-template", { "template": "${fileName:text${fileName}text}" } ],
+    [ "../../formatter-template", { "template": "${fileName:${fileName}}" } ],
+    [ "../../formatter-template", { "template": "${fileName:${fileName:${fileName}}}" } ]
+  ]
+}

test/formatter-template/simple.md

@@ -0,0 +1 @@
+# Heading

test/markdownlint-cli2-test-cases.js

@@ -960,6 +960,13 @@ const testCases = ({
     }
   });
 
+  testCase({
+    "name": "formatter-template",
+    "args": [ "*.md" ],
+    "exitCode": 1,
+    "usesRequire": true
+  });
+
   testCase({
     "name": "nested-files",
     "args": [ "**/*.md" ],

test/markdownlint-cli2-test.js

@@ -111,7 +111,7 @@ test("validateMarkdownlintConfigSchema", async (t) => {
 });
 
 test("validateMarkdownlintCli2ConfigSchema", async (t) => {
-  t.plan(91);
+  t.plan(92);
 
   // Validate schema
   // @ts-ignore

test/snapshots/markdownlint-cli2-test-exec.js.md

@@ -5890,6 +5890,32 @@ Generated by [AVA](https://avajs.dev).
       Summary: 15 error(s)`,
     }
 
+## formatter-template (exec)
+
+> Snapshot 1
+
+    {
+      exitCode: 1,
+      formatterCodeQuality: '',
+      formatterJson: '',
+      formatterJunit: '',
+      formatterSarif: '',
+      stderr: `${invalid}␊
+      simple.md␊
+      simple.mdsimple.mdsimple.md␊
+      text{text}text␊
+      text{text␊
+      texttext}␊
+      text${invalid}text␊
+      textsimple.mdtext␊
+      simple.md␊
+      ${fileName}`,
+      stdout: `markdownlint-cli2 vX.Y.Z (markdownlint vX.Y.Z)␊
+      Finding: *.md␊
+      Linting: 1 file(s)␊
+      Summary: 1 error(s)`,
+    }
+
 ## nested-files (exec)
 
 > Snapshot 1

test/snapshots/markdownlint-cli2-test-exec.js.snap

@@ -5078,6 +5078,34 @@ Generated by [AVA](https://avajs.dev).
       `,
     }
 
+## formatter-template (main)
+
+> Snapshot 1
+
+    {
+      exitCode: 1,
+      formatterCodeQuality: '',
+      formatterJson: '',
+      formatterJunit: '',
+      formatterSarif: '',
+      stderr: `${invalid}␊
+      simple.md␊
+      simple.mdsimple.mdsimple.md␊
+      text{text}text␊
+      text{text␊
+      texttext}␊
+      text${invalid}text␊
+      textsimple.mdtext␊
+      simple.md␊
+      ${fileName}␊
+      `,
+      stdout: `markdownlint-cli2 vX.Y.Z (markdownlint vX.Y.Z)␊
+      Finding: *.md␊
+      Linting: 1 file(s)␊
+      Summary: 1 error(s)␊
+      `,
+    }
+
 ## nested-files (main)
 
 > Snapshot 1