Implement F631 (AssertTuple) (#99)

README.md

@@ -114,6 +114,7 @@ OPTIONS:
 | F401 | UnusedImport | `...` imported but unused |
 | F403 | ImportStarUsage | Unable to detect undefined names |
 | F541 | FStringMissingPlaceholders | f-string without any placeholders |
+| F631 | AssertTuple | Assert test is a non-empty tuple, which is always `True` |
 | F634 | IfTuple | If test is a tuple, which is always `True` |
 | F704 | YieldOutsideFunction | a `yield` or `yield from` statement outside of a function/method |
 | F706 | ReturnOutsideFunction | a `return` statement outside of a function/method |

resources/test/fixtures/F631.py

@@ -0,0 +1,4 @@
+assert (False, "x")
+assert (False,)
+assert ()
+assert True

resources/test/fixtures/pyproject.toml

@@ -6,6 +6,7 @@ select = [
     "F401",
     "F403",
     "F541",
+    "F631",
     "F634",
     "F704",
     "F706",

src/check_ast.rs

@@ -283,6 +283,18 @@ impl Visitor for Checker<'_> {
                 }
             }
             StmtKind::AugAssign { target, .. } => self.handle_node_load(target),
+            StmtKind::Assert { test, .. } => {
+                if self.settings.select.contains(CheckKind::AssertTuple.code()) {
+                    if let ExprKind::Tuple { elts, .. } = &test.node {
+                        if !elts.is_empty() {
+                            self.checks.push(Check {
+                                kind: CheckKind::AssertTuple,
+                                location: stmt.location,
+                            });
+                        }
+                    }
+                }
+            }
             _ => {}
         }
 

src/checks.rs

@@ -12,6 +12,7 @@ pub enum CheckCode {
     F401,
     F403,
     F541,
+    F631,
     F634,
     F704,
     F706,
@@ -33,6 +34,7 @@ impl FromStr for CheckCode {
             "F401" => Ok(CheckCode::F401),
             "F403" => Ok(CheckCode::F403),
             "F541" => Ok(CheckCode::F541),
+            "F631" => Ok(CheckCode::F631),
             "F634" => Ok(CheckCode::F634),
             "F704" => Ok(CheckCode::F704),
             "F706" => Ok(CheckCode::F706),
@@ -55,6 +57,7 @@ impl CheckCode {
             CheckCode::F401 => "F401",
             CheckCode::F403 => "F403",
             CheckCode::F541 => "F541",
+            CheckCode::F631 => "F631",
             CheckCode::F634 => "F634",
             CheckCode::F704 => "F704",
             CheckCode::F706 => "F706",
@@ -75,6 +78,7 @@ impl CheckCode {
             CheckCode::F401 => &LintSource::AST,
             CheckCode::F403 => &LintSource::AST,
             CheckCode::F541 => &LintSource::AST,
+            CheckCode::F631 => &LintSource::AST,
             CheckCode::F634 => &LintSource::AST,
             CheckCode::F704 => &LintSource::AST,
             CheckCode::F706 => &LintSource::AST,
@@ -99,6 +103,7 @@ pub enum LintSource {
 pub enum CheckKind {
     DuplicateArgumentName,
     FStringMissingPlaceholders,
+    AssertTuple,
     IfTuple,
     ImportStarUsage,
     LineTooLong,
@@ -119,6 +124,7 @@ impl CheckKind {
         match self {
             CheckKind::DuplicateArgumentName => "DuplicateArgumentName",
             CheckKind::FStringMissingPlaceholders => "FStringMissingPlaceholders",
+            CheckKind::AssertTuple => "AssertTuple",
             CheckKind::IfTuple => "IfTuple",
             CheckKind::ImportStarUsage => "ImportStarUsage",
             CheckKind::LineTooLong => "LineTooLong",
@@ -139,6 +145,7 @@ impl CheckKind {
         match self {
             CheckKind::DuplicateArgumentName => &CheckCode::F831,
             CheckKind::FStringMissingPlaceholders => &CheckCode::F541,
+            CheckKind::AssertTuple => &CheckCode::F631,
             CheckKind::IfTuple => &CheckCode::F634,
             CheckKind::ImportStarUsage => &CheckCode::F403,
             CheckKind::LineTooLong => &CheckCode::E501,
@@ -163,6 +170,9 @@ impl CheckKind {
             CheckKind::FStringMissingPlaceholders => {
                 "f-string without any placeholders".to_string()
             }
+            CheckKind::AssertTuple => {
+                "Assert test is a non-empty tuple, which is always `True`".to_string()
+            }
             CheckKind::IfTuple => "If test is a tuple, which is always `True`".to_string(),
             CheckKind::ImportStarUsage => "Unable to detect undefined names".to_string(),
             CheckKind::LineTooLong => "Line too long".to_string(),

src/linter.rs

@@ -191,6 +191,37 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn f631() -> Result<()> {
+        let actual = check_path(
+            Path::new("./resources/test/fixtures/F631.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::F631]),
+            },
+            &cache::Mode::None,
+        )?;
+        let expected = vec![
+            Message {
+                kind: CheckKind::AssertTuple,
+                location: Location::new(1, 1),
+                filename: "./resources/test/fixtures/F631.py".to_string(),
+            },
+            Message {
+                kind: CheckKind::AssertTuple,
+                location: Location::new(2, 1),
+                filename: "./resources/test/fixtures/F631.py".to_string(),
+            },
+        ];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
     #[test]
     fn f634() -> Result<()> {
         let actual = check_path(

src/pyproject.rs

@@ -241,6 +241,7 @@ other-attribute = 1
                     CheckCode::F401,
                     CheckCode::F403,
                     CheckCode::F541,
+                    CheckCode::F631,
                     CheckCode::F634,
                     CheckCode::F704,
                     CheckCode::F706,

src/settings.rs

@@ -48,6 +48,7 @@ impl Settings {
                     CheckCode::F401,
                     CheckCode::F403,
                     CheckCode::F541,
+                    CheckCode::F631,
                     CheckCode::F634,
                     CheckCode::F706,
                     CheckCode::F831,