Initial test :)

crates/ruff/resources/test/fixtures/jupyter/line_magics.ipynb

@@ -0,0 +1,41 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "eab4754a-d6df-4b41-8ee8-7e23aef440f9",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "\n",
+    "%matplotlib inline\n",
+    "\n",
+    "import os\n",
+    "\n",
+    "_ = math.pi"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python (ruff)",
+   "language": "python",
+   "name": "ruff"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

crates/ruff/resources/test/fixtures/jupyter/line_magics_expected.ipynb

@@ -0,0 +1,40 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "cad32845-44f9-4a53-8b8c-a6b1bb3f3378",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import math\n",
+    "\n",
+    "%matplotlib inline\n",
+    "\n",
+    "\n",
+    "_ = math.pi"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python (ruff)",
+   "language": "python",
+   "name": "ruff"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

crates/ruff/src/jupyter/notebook.rs

@@ -552,6 +552,18 @@ print("after empty cells")
         Ok(())
     }
 
+    #[test]
+    fn test_line_magics() -> Result<()> {
+        let path = "line_magics.ipynb".to_string();
+        let (diagnostics, source_kind) = test_notebook_path(
+            &path,
+            Path::new("line_magics_expected.ipynb"),
+            &settings::Settings::for_rule(Rule::UnusedImport),
+        )?;
+        assert_messages!(diagnostics, path, source_kind);
+        Ok(())
+    }
+
     #[test]
     fn test_json_consistency() -> Result<()> {
         let path = "before_fix.ipynb".to_string();

crates/ruff/src/jupyter/snapshots/ruff__jupyter__notebook__tests__line_magics.snap

@@ -0,0 +1,21 @@
+---
+source: crates/ruff/src/jupyter/notebook.rs
+---
+line_magics.ipynb:cell 1:5:8: F401 [*] `os` imported but unused
+  |
+3 | %matplotlib inline
+4 | 
+5 | import os
+  |        ^^ F401
+  |
+  = help: Remove unused import: `os`
+
+ℹ Fix
+2 2 | 
+3 3 | %matplotlib inline
+4 4 | 
+5   |-import os
+6 5 | 
+7 6 | _ = math.pi
+
+