@@ -2478,3 +2478,92 @@ fn markdown_formatting_preview_enabled() -> Result<()> {
     "#);
     Ok(())
 }
+
+#[test]
+fn markdown_formatting_stdin() -> Result<()> {
+    let test = CliTest::new()?;
+
+    let fixtures = Path::new("resources").join("test").join("fixtures");
+    let unformatted = fs::read(fixtures.join("unformatted.md")).unwrap();
+    assert_cmd_snapshot!(test.format_command()
+        .args(["--isolated", "--preview", "--stdin-filename", "unformatted.md"])
+        .arg("-")
+        .pass_stdin(unformatted), @r#"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    This is a markdown document with some fenced code blocks with unformatted code.
+
+    Unlabeled Python code:
+
+    ```
+    print( "hello" )
+    ```
+
+    Unlabeled Rust code:
+
+    ```
+    fn thing() {
+        println!( "hello" );
+    }
+    ```
+
+    Labeled Python code:
+
+    ```py
+    print("hello")
+
+
+    def foo():
+        pass
+    ```
+
+    Labeled Python stub:
+
+    ```pyi
+    print("hello")
+
+    def foo():
+        pass
+    ```
+
+    Labeled Rust code:
+    ```rust
+    fn thing() {
+        println!( "hello" );
+    }
+    ```
+
+    Indented code blocks should also work:
+
+    * List item
+
+      ```py
+      print("hello")
+      ```
+
+    Block quoted code blocks may not be supported:
+
+    > Quoted text
+    >
+    > ```py
+    > print( "hello" )
+    > ```
+
+
+    Blacken-docs supports ignore directives:
+
+    <!-- blacken-docs:off -->
+    ```py
+    print("hello")
+    ```
+    <!-- blacken-docs:on -->
+
+    ```py
+    print("hello")
+    ```
+
+    ----- stderr -----
+    "#);
+    Ok(())
+}
@@ -130,6 +130,8 @@ impl SourceKind {
             Ok(notebook
                 .is_python_notebook()
                 .then_some(Self::IpyNotebook(Box::new(notebook))))
+        } else if source_type.is_markdown() {
+            Ok(Some(Self::Markdown(source_code)))
         } else {
             Ok(Some(Self::Python(source_code)))
         }
Original file line number	Diff line number	Diff line change
`@@ -130,6 +130,8 @@ impl SourceKind {`
`130`	`130`	`Ok(notebook`
`131`	`131`	`.is_python_notebook()`
`132`	`132`	`.then_some(Self::IpyNotebook(Box::new(notebook))))`
	`133`	`+ } else if source_type.is_markdown() {`
	`134`	`+ Ok(Some(Self::Markdown(source_code)))`
`133`	`135`	`} else {`
`134`	`136`	`Ok(Some(Self::Python(source_code)))`
`135`	`137`	`}`