Show partial fixability indicator in statistics output (#21513)

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Micha Reiser <micha@reiser.io>

crates/ruff/src/printer.rs

@@ -34,9 +34,21 @@ struct ExpandedStatistics<'a> {
     code: Option<&'a SecondaryCode>,
     name: &'static str,
     count: usize,
-    fixable: bool,
+    #[serde(rename = "fixable")]
+    all_fixable: bool,
+    fixable_count: usize,
 }
 
+impl ExpandedStatistics<'_> {
+    fn any_fixable(&self) -> bool {
+        self.fixable_count > 0
+    }
+}
+
+/// Accumulator type for grouping diagnostics by code.
+/// Format: (`code`, `representative_diagnostic`, `total_count`, `fixable_count`)
+type DiagnosticGroup<'a> = (Option<&'a SecondaryCode>, &'a Diagnostic, usize, usize);
+
 pub(crate) struct Printer {
     format: OutputFormat,
     log_level: LogLevel,
@@ -133,7 +145,7 @@ impl Printer {
                         if fixables.applicable > 0 {
                             writeln!(
                                 writer,
-                                "{fix_prefix} {} fixable with the --fix option.",
+                                "{fix_prefix} {} fixable with the `--fix` option.",
                                 fixables.applicable
                             )?;
                         }
@@ -256,35 +268,41 @@ impl Printer {
         diagnostics: &Diagnostics,
         writer: &mut dyn Write,
     ) -> Result<()> {
+        let required_applicability = self.unsafe_fixes.required_applicability();
         let statistics: Vec<ExpandedStatistics> = diagnostics
             .inner
             .iter()
-            .map(|message| (message.secondary_code(), message))
+            .sorted_by_key(|diagnostic| diagnostic.secondary_code())
-            .sorted_by_key(|(code, message)| (*code, message.fixable()))
+            .fold(vec![], |mut acc: Vec<DiagnosticGroup>, diagnostic| {
-            .fold(
+                let is_fixable = diagnostic
-                vec![],
+                    .fix()
-                |mut acc: Vec<((Option<&SecondaryCode>, &Diagnostic), usize)>, (code, message)| {
+                    .is_some_and(|fix| fix.applies(required_applicability));
-                    if let Some(((prev_code, _prev_message), count)) = acc.last_mut() {
+                let code = diagnostic.secondary_code();
-                        if *prev_code == code {
+
-                            *count += 1;
+                if let Some((prev_code, _prev_message, count, fixable_count)) = acc.last_mut() {
-                            return acc;
+                    if *prev_code == code {
+                        *count += 1;
+                        if is_fixable {
+                            *fixable_count += 1;
                         }
+                        return acc;
                     }
-                    acc.push(((code, message), 1));
+                }
-                    acc
+                acc.push((code, diagnostic, 1, usize::from(is_fixable)));
+                acc
+            })
+            .iter()
+            .map(
+                |&(code, message, count, fixable_count)| ExpandedStatistics {
+                    code,
+                    name: message.name(),
+                    count,
+                    // Backward compatibility: `fixable` is true only when all violations are fixable.
+                    // See: https://github.com/astral-sh/ruff/pull/21513
+                    all_fixable: fixable_count == count,
+                    fixable_count,
                 },
             )
-            .iter()
-            .map(|&((code, message), count)| ExpandedStatistics {
-                code,
-                name: message.name(),
-                count,
-                fixable: if let Some(fix) = message.fix() {
-                    fix.applies(self.unsafe_fixes.required_applicability())
-                } else {
-                    false
-                },
-            })
             .sorted_by_key(|statistic| Reverse(statistic.count))
             .collect();
 
@@ -308,13 +326,14 @@ impl Printer {
                     .map(|statistic| statistic.code.map_or(0, |s| s.len()))
                     .max()
                     .unwrap();
-                let any_fixable = statistics.iter().any(|statistic| statistic.fixable);
+                let any_fixable = statistics.iter().any(ExpandedStatistics::any_fixable);
 
-                let fixable = format!("[{}] ", "*".cyan());
+                let all_fixable = format!("[{}] ", "*".cyan());
+                let partially_fixable = format!("[{}] ", "-".cyan());
                 let unfixable = "[ ] ";
 
                 // By default, we mimic Flake8's `--statistics` format.
-                for statistic in statistics {
+                for statistic in &statistics {
                     writeln!(
                         writer,
                         "{:>count_width$}\t{:<code_width$}\t{}{}",
@@ -326,8 +345,10 @@ impl Printer {
                             .red()
                             .bold(),
                         if any_fixable {
-                            if statistic.fixable {
+                            if statistic.all_fixable {
-                                &fixable
+                                &all_fixable
+                            } else if statistic.any_fixable() {
+                                &partially_fixable
                             } else {
                                 unfixable
                             }

crates/ruff/tests/integration_test.rs

@@ -1043,7 +1043,7 @@ def mvce(keys, values):
     ----- stdout -----
     1	C416	[*] unnecessary-comprehension
     Found 1 error.
-    [*] 1 fixable with the --fix option.
+    [*] 1 fixable with the `--fix` option.
 
     ----- stderr -----
     ");
@@ -1073,7 +1073,8 @@ def mvce(keys, values):
         "code": "C416",
         "name": "unnecessary-comprehension",
         "count": 1,
-        "fixable": false
+        "fixable": false,
+        "fixable_count": 0
       }
     ]
 
@@ -1106,7 +1107,8 @@ def mvce(keys, values):
         "code": "C416",
         "name": "unnecessary-comprehension",
         "count": 1,
-        "fixable": true
+        "fixable": true,
+        "fixable_count": 1
       }
     ]
 
@@ -1114,6 +1116,54 @@ def mvce(keys, values):
     "#);
 }
 
+#[test]
+fn show_statistics_json_partial_fix() {
+    let mut cmd = RuffCheck::default()
+        .args([
+            "--select",
+            "UP035",
+            "--statistics",
+            "--output-format",
+            "json",
+        ])
+        .build();
+    assert_cmd_snapshot!(cmd
+        .pass_stdin("from typing import List, AsyncGenerator"), @r#"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    [
+      {
+        "code": "UP035",
+        "name": "deprecated-import",
+        "count": 2,
+        "fixable": false,
+        "fixable_count": 1
+      }
+    ]
+
+    ----- stderr -----
+    "#);
+}
+
+#[test]
+fn show_statistics_partial_fix() {
+    let mut cmd = RuffCheck::default()
+        .args(["--select", "UP035", "--statistics"])
+        .build();
+    assert_cmd_snapshot!(cmd
+        .pass_stdin("from typing import List, AsyncGenerator"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    2	UP035	[-] deprecated-import
+    Found 2 errors.
+    [*] 1 fixable with the `--fix` option.
+
+    ----- stderr -----
+    ");
+}
+
 #[test]
 fn show_statistics_syntax_errors() {
     let mut cmd = RuffCheck::default()
@@ -1810,7 +1860,7 @@ fn check_no_hint_for_hidden_unsafe_fixes_when_disabled() {
     --> -:1:1
 
     Found 2 errors.
-    [*] 1 fixable with the --fix option.
+    [*] 1 fixable with the `--fix` option.
 
     ----- stderr -----
     ");
@@ -1853,7 +1903,7 @@ fn check_shows_unsafe_fixes_with_opt_in() {
     --> -:1:1
 
     Found 2 errors.
-    [*] 2 fixable with the --fix option.
+    [*] 2 fixable with the `--fix` option.
 
     ----- stderr -----
     ");

crates/ruff_linter/resources/test/project/README.md

@@ -17,7 +17,7 @@ crates/ruff_linter/resources/test/project/examples/docs/docs/file.py:8:5: F841 [
 crates/ruff_linter/resources/test/project/project/file.py:1:8: F401 [*] `os` imported but unused
 crates/ruff_linter/resources/test/project/project/import_file.py:1:1: I001 [*] Import block is un-sorted or un-formatted
 Found 7 errors.
-[*] 7 potentially fixable with the --fix option.
+[*] 7 potentially fixable with the `--fix` option.
 ```
 
 Running from the project directory itself should exhibit the same behavior:
@@ -32,7 +32,7 @@ examples/docs/docs/file.py:8:5: F841 [*] Local variable `x` is assigned to but n
 project/file.py:1:8: F401 [*] `os` imported but unused
 project/import_file.py:1:1: I001 [*] Import block is un-sorted or un-formatted
 Found 7 errors.
-[*] 7 potentially fixable with the --fix option.
+[*] 7 potentially fixable with the `--fix` option.
 ```
 
 Running from the sub-package directory should exhibit the same behavior, but omit the top-level
@@ -43,7 +43,7 @@ files:
 docs/file.py:1:1: I001 [*] Import block is un-sorted or un-formatted
 docs/file.py:8:5: F841 [*] Local variable `x` is assigned to but never used
 Found 2 errors.
-[*] 2 potentially fixable with the --fix option.
+[*] 2 potentially fixable with the `--fix` option.
 ```
 
 `--config` should force Ruff to use the specified `pyproject.toml` for all files, and resolve
@@ -61,7 +61,7 @@ crates/ruff_linter/resources/test/project/examples/docs/docs/file.py:4:27: F401
 crates/ruff_linter/resources/test/project/examples/excluded/script.py:1:8: F401 [*] `os` imported but unused
 crates/ruff_linter/resources/test/project/project/file.py:1:8: F401 [*] `os` imported but unused
 Found 9 errors.
-[*] 9 potentially fixable with the --fix option.
+[*] 9 potentially fixable with the `--fix` option.
 ```
 
 Running from a parent directory should "ignore" the `exclude` (hence, `concepts/file.py` gets
@@ -74,7 +74,7 @@ docs/docs/file.py:1:1: I001 [*] Import block is un-sorted or un-formatted
 docs/docs/file.py:8:5: F841 [*] Local variable `x` is assigned to but never used
 excluded/script.py:5:5: F841 [*] Local variable `x` is assigned to but never used
 Found 4 errors.
-[*] 4 potentially fixable with the --fix option.
+[*] 4 potentially fixable with the `--fix` option.
 ```
 
 Passing an excluded directory directly should report errors in the contained files:
@@ -83,7 +83,7 @@ Passing an excluded directory directly should report errors in the contained fil
 ∴ cargo run -p ruff -- check crates/ruff_linter/resources/test/project/examples/excluded/
 crates/ruff_linter/resources/test/project/examples/excluded/script.py:1:8: F401 [*] `os` imported but unused
 Found 1 error.
-[*] 1 potentially fixable with the --fix option.
+[*] 1 potentially fixable with the `--fix` option.
 ```
 
 Unless we `--force-exclude`:

docs/faq.md

@@ -454,7 +454,7 @@ Untitled.ipynb:cell_1:2:5: F841 Local variable `x` is assigned to but never used
 Untitled.ipynb:cell_2:1:1: E402 Module level import not at top of file
 Untitled.ipynb:cell_2:1:8: F401 `os` imported but unused
 Found 3 errors.
-1 potentially fixable with the --fix option.
+1 potentially fixable with the `--fix` option.
 ```
 
 ## Does Ruff support NumPy- or Google-style docstrings?