feat: add markdown support to deno fmt (#8887)

This commit adds support for formatting markdown files with "deno fmt".

Additionally "--ext={js|jsx|ts|tsx|md}" flag was added to "deno fmt"
that allows to specify file type when providing contents over stdio.

7 files changed, 106 insertions, 16 deletions

diff --git a/cli/tests/badly_formatted.md b/cli/tests/badly_formatted.md
new file mode 100644
index 000000000..adffe3e46
--- /dev/null
+++ b/cli/tests/badly_formatted.md
@@ -0,0 +1,28 @@
+# Hello      Markdown
+
+```js
+console.log("Hello World"
+
+)
+```
+
+```javascript
+console.log("Hello World2"
+
+)
+```
+
+```ts
+
+function hello(name: string    ) {
+                  console.log(name);
+};
+
+hello(        "alice");
+```
+
+```typescript
+function foo(): number {
+  return       2;
+}
+```
\ No newline at end of file
diff --git a/cli/tests/badly_formatted_fixed.md b/cli/tests/badly_formatted_fixed.md
new file mode 100644
index 000000000..359a8aead
--- /dev/null
+++ b/cli/tests/badly_formatted_fixed.md
@@ -0,0 +1,23 @@
+# Hello Markdown
+
+```js
+console.log("Hello World");
+```
+
+```javascript
+console.log("Hello World2");
+```
+
+```ts
+function hello(name: string) {
+  console.log(name);
+}
+
+hello("alice");
+```
+
+```typescript
+function foo(): number {
+  return 2;
+}
+```
diff --git a/cli/tests/fmt/expected_fmt_check_formatted_files.out b/cli/tests/fmt/expected_fmt_check_formatted_files.out
index 158c556c2..7c1e471b9 100644
--- a/cli/tests/fmt/expected_fmt_check_formatted_files.out
+++ b/cli/tests/fmt/expected_fmt_check_formatted_files.out
@@ -1 +1 @@
-Checked 2 files
+Checked 3 files
diff --git a/cli/tests/fmt/expected_fmt_check_ignore.out b/cli/tests/fmt/expected_fmt_check_ignore.out
index c05ac45a1..158c556c2 100644
--- a/cli/tests/fmt/expected_fmt_check_ignore.out
+++ b/cli/tests/fmt/expected_fmt_check_ignore.out
@@ -1 +1 @@
-Checked 1 file
+Checked 2 files
diff --git a/cli/tests/fmt/expected_fmt_check_tests_dir.out b/cli/tests/fmt/expected_fmt_check_tests_dir.out
index 00d7cb3fa..e2dc2b4ae 100644
--- a/cli/tests/fmt/expected_fmt_check_tests_dir.out
+++ b/cli/tests/fmt/expected_fmt_check_tests_dir.out
@@ -1,2 +1,2 @@
 [WILDCARD]
-error: Found 5 not formatted files in [WILDCARD] files
+error: Found 6 not formatted files in [WILDCARD] files
diff --git a/cli/tests/fmt/formatted3.md b/cli/tests/fmt/formatted3.md
new file mode 100644
index 000000000..e6e616584
--- /dev/null
+++ b/cli/tests/fmt/formatted3.md
@@ -0,0 +1,17 @@
+# Hello
+
+```js
+function foo() {
+  return 42;
+}
+
+foo();
+```
+
+```ts
+function bar(): number {
+  return 42;
+}
+
+bar();
+```
diff --git a/cli/tests/integration_tests.rs b/cli/tests/integration_tests.rs
index 0af4709fb..80a7222e5 100644
--- a/cli/tests/integration_tests.rs
+++ b/cli/tests/integration_tests.rs
@@ -511,20 +511,31 @@ fn cache_invalidation_test_no_check() {
 #[test]
 fn fmt_test() {
   let t = TempDir::new().expect("tempdir fail");
-  let fixed = util::root_path().join("cli/tests/badly_formatted_fixed.js");
-  let badly_formatted_original =
+  let fixed_js = util::root_path().join("cli/tests/badly_formatted_fixed.js");
+  let fixed_md = util::root_path().join("cli/tests/badly_formatted_fixed.md");
+  let badly_formatted_original_js =
     util::root_path().join("cli/tests/badly_formatted.mjs");
-  let badly_formatted = t.path().join("badly_formatted.js");
-  let badly_formatted_str = badly_formatted.to_str().unwrap();
-  std::fs::copy(&badly_formatted_original, &badly_formatted)
+  let badly_formatted_original_md =
+    util::root_path().join("cli/tests/badly_formatted.md");
+  let badly_formatted_js = t.path().join("badly_formatted.js");
+  let badly_formatted_md = t.path().join("badly_formatted.md");
+  let badly_formatted_js_str = badly_formatted_js.to_str().unwrap();
+  let badly_formatted_md_str = badly_formatted_md.to_str().unwrap();
+  std::fs::copy(&badly_formatted_original_js, &badly_formatted_js)
+    .expect("Failed to copy file");
+  std::fs::copy(&badly_formatted_original_md, &badly_formatted_md)
     .expect("Failed to copy file");
   // First, check formatting by ignoring the badly formatted file.
   let status = util::deno_cmd()
     .current_dir(util::root_path())
     .arg("fmt")
-    .arg(format!("--ignore={}", badly_formatted_str))
+    .arg(format!(
+      "--ignore={},{}",
+      badly_formatted_js_str, badly_formatted_md_str
+    ))
     .arg("--check")
-    .arg(badly_formatted_str)
+    .arg(badly_formatted_js_str)
+    .arg(badly_formatted_md_str)
     .spawn()
     .expect("Failed to spawn script")
     .wait()
@@ -535,7 +546,8 @@ fn fmt_test() {
     .current_dir(util::root_path())
     .arg("fmt")
     .arg("--check")
-    .arg(badly_formatted_str)
+    .arg(badly_formatted_js_str)
+    .arg(badly_formatted_md_str)
     .spawn()
     .expect("Failed to spawn script")
     .wait()
@@ -545,15 +557,19 @@ fn fmt_test() {
   let status = util::deno_cmd()
     .current_dir(util::root_path())
     .arg("fmt")
-    .arg(badly_formatted_str)
+    .arg(badly_formatted_js_str)
+    .arg(badly_formatted_md_str)
     .spawn()
     .expect("Failed to spawn script")
     .wait()
     .expect("Failed to wait for child process");
   assert!(status.success());
-  let expected = std::fs::read_to_string(fixed).unwrap();
-  let actual = std::fs::read_to_string(badly_formatted).unwrap();
-  assert_eq!(expected, actual);
+  let expected_js = std::fs::read_to_string(fixed_js).unwrap();
+  let expected_md = std::fs::read_to_string(fixed_md).unwrap();
+  let actual_js = std::fs::read_to_string(badly_formatted_js).unwrap();
+  let actual_md = std::fs::read_to_string(badly_formatted_md).unwrap();
+  assert_eq!(expected_js, actual_js);
+  assert_eq!(expected_md, actual_md);
 }
 
 // Helper function to skip watcher output that contains "Restarting"
@@ -2751,7 +2767,7 @@ itest!(fmt_quiet_check_fmt_dir {
 });
 
 itest!(fmt_check_formatted_files {
-  args: "fmt --check fmt/formatted1.js fmt/formatted2.ts",
+  args: "fmt --check fmt/formatted1.js fmt/formatted2.ts fmt/formatted3.md",
   output: "fmt/expected_fmt_check_formatted_files.out",
   exit_code: 0,
 });
@@ -2768,6 +2784,12 @@ itest!(fmt_stdin {
   output_str: Some("const a = 1;\n"),
 });
 
+itest!(fmt_stdin_markdown {
+  args: "fmt --ext=md -",
+  input: Some("# Hello      Markdown\n```ts\nconsole.log( \"text\")\n```\n"),
+  output_str: Some("# Hello Markdown\n\n```ts\nconsole.log(\"text\");\n```\n"),
+});
+
 itest!(fmt_stdin_check_formatted {
   args: "fmt --check -",
   input: Some("const a = 1;\n"),