Show all parse errors as diagnostics

crates/ruff/tests/integration_test.rs

@@ -727,15 +727,32 @@ fn stdin_format_jupyter() {
 fn stdin_parse_error() {
     let mut cmd = RuffCheck::default().build();
     assert_cmd_snapshot!(cmd
-        .pass_stdin("from foo import =\n"), @r###"
+        .pass_stdin("from foo import\n"), @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:17: E999 SyntaxError: Expected an import name
+    -:1:16: E999 SyntaxError: Expected one or more symbol names after import
     Found 1 error.
 
     ----- stderr -----
-    error: Failed to parse at 1:17: Expected an import name
+    error: Failed to parse at 1:16: Expected one or more symbol names after import
+    "###);
+}
+
+#[test]
+fn stdin_multiple_parse_error() {
+    let mut cmd = RuffCheck::default().build();
+    assert_cmd_snapshot!(cmd
+        .pass_stdin("from foo import\nbar =\n"), @r###"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    -:1:16: E999 SyntaxError: Expected one or more symbol names after import
+    -:2:6: E999 SyntaxError: Expected an expression
+    Found 2 errors.
+
+    ----- stderr -----
+    error: Failed to parse at 1:16: Expected one or more symbol names after import
     "###);
 }
 

crates/ruff_linter/src/linter.rs

@@ -192,15 +192,17 @@ pub fn check_path(
                     doc_lines.extend(doc_lines_from_ast(parsed.suite(), locator));
                 }
             }
-            Err(parse_error) => {
+            Err(parse_errors) => {
                 // Always add a diagnostic for the syntax error, regardless of whether
                 // `Rule::SyntaxError` is enabled. We avoid propagating the syntax error
                 // if it's disabled via any of the usual mechanisms (e.g., `noqa`,
                 // `per-file-ignores`), and the easiest way to detect that suppression is
                 // to see if the diagnostic persists to the end of the function.
-                pycodestyle::rules::syntax_error(&mut diagnostics, parse_error, locator);
+                for parse_error in parse_errors {
+                    pycodestyle::rules::syntax_error(&mut diagnostics, parse_error, locator);
+                }
                 // TODO(dhruvmanila): Remove this clone
-                error = Some(parse_error.clone());
+                error = parse_errors.iter().next().cloned();
             }
         }
     }

crates/ruff_python_parser/src/lib.rs

@@ -274,11 +274,11 @@ impl<T> Parsed<T> {
 
     /// Returns the [`Parsed`] output as a [`Result`], returning [`Ok`] if it has no syntax errors,
     /// or [`Err`] containing the first [`ParseError`] encountered.
-    pub fn as_result(&self) -> Result<&Parsed<T>, &ParseError> {
-        if let [error, ..] = self.errors() {
-            Err(error)
-        } else {
+    pub fn as_result(&self) -> Result<&Parsed<T>, &[ParseError]> {
+        if self.is_valid() {
             Ok(self)
+        } else {
+            Err(&self.errors)
         }
     }
 

crates/ruff_python_parser/tests/fixtures.rs

@@ -126,8 +126,7 @@ fn test_invalid_syntax(input_path: &Path) {
 #[allow(clippy::print_stdout)]
 fn parser_quick_test() {
     let source = "\
-def foo()
-    pass
+from foo import
 ";
 
     let parsed = parse_unchecked(source, Mode::Module);