feat(linter): eslint-plugin-unicorn no-object-as-default-parameter (#1162)

crates/oxc_linter/src/rules.rs

@@ -148,6 +148,7 @@ mod unicorn {
     pub mod no_instanceof_array;
     pub mod no_invalid_remove_event_listener;
     pub mod no_new_array;
+    pub mod no_object_as_default_parameter;
     pub mod no_thenable;
     pub mod no_unnecessary_await;
     pub mod prefer_array_flat_map;
@@ -276,18 +277,19 @@ oxc_macros::declare_all_lint_rules! {
     unicorn::no_instanceof_array,
     unicorn::no_invalid_remove_event_listener,
     unicorn::no_new_array,
+    unicorn::no_object_as_default_parameter,
     unicorn::no_thenable,
     unicorn::no_unnecessary_await,
     unicorn::prefer_array_flat_map,
     unicorn::prefer_date_now,
     unicorn::prefer_logical_operator_over_ternary,
+    unicorn::prefer_query_selector,
+    unicorn::prefer_string_trim_start_end,
     unicorn::prefer_type_error,
     unicorn::require_number_to_fixed_digits_argument,
     unicorn::switch_case_braces,
     unicorn::text_encoding_identifier_case,
     unicorn::throw_new_error,
-    unicorn::prefer_string_trim_start_end,
-    unicorn::prefer_query_selector,
     react::jsx_key,
     react::jsx_no_comment_text_nodes,
     react::jsx_no_duplicate_props,

crates/oxc_linter/src/rules/unicorn/no_object_as_default_parameter.rs

@@ -0,0 +1,132 @@
+use oxc_ast::{
+    ast::{BindingPatternKind, Expression},
+    AstKind,
+};
+use oxc_diagnostics::{
+    miette::{self, Diagnostic},
+    thiserror::{self, Error},
+};
+use oxc_macros::declare_oxc_lint;
+use oxc_span::Span;
+
+use crate::{context::LintContext, rule::Rule, AstNode};
+
+#[derive(Debug, Error, Diagnostic)]
+enum NoObjectAsDefaultParameterDiagnostic {
+    #[error("eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `{1}`.")]
+    #[diagnostic(severity(warning))]
+    Identifier(#[label] Span, String),
+    #[error("eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default")]
+    #[diagnostic(severity(warning))]
+    NonIdentifier(#[label] Span),
+}
+
+#[derive(Debug, Default, Clone)]
+pub struct NoObjectAsDefaultParameter;
+
+declare_oxc_lint!(
+    /// ### What it does
+    ///
+    /// Disallow the use of an object literal as a default value for a parameter.
+    ///
+    /// ### Why is this bad?
+    ///
+    /// Default parameters should not be passed to a function through an object literal. The `foo = {a: false}` parameter works fine if only used with one option. As soon as additional options are added, you risk replacing the whole `foo = {a: false, b: true}` object when passing only one option: `{a: true}`. For this reason, object destructuring should be used instead.
+    ///
+    /// ### Example
+    /// ```javascript
+    /// // Bad
+    /// function foo(foo = {a: false}) {}
+    ///
+    /// // Good
+    /// function foo({a = false} = {}) {}
+    /// ```
+    NoObjectAsDefaultParameter,
+    pedantic
+);
+
+impl Rule for NoObjectAsDefaultParameter {
+    fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {
+        let AstKind::AssignmentPattern(assignment_pat) = node.kind() else { return };
+
+        let Expression::ObjectExpression(object_expr) = &assignment_pat.right else {
+            return;
+        };
+
+        if object_expr.properties.len() == 0 {
+            return;
+        }
+
+        let Some(parent) = ctx.nodes().parent_node(node.id()) else { return };
+
+        if !matches!(parent.kind(), AstKind::FormalParameter(_)) {
+            return;
+        }
+
+        if let BindingPatternKind::BindingIdentifier(binding_id) = &assignment_pat.left.kind {
+            ctx.diagnostic(NoObjectAsDefaultParameterDiagnostic::Identifier(
+                object_expr.span,
+                binding_id.name.to_string(),
+            ));
+            return;
+        }
+
+        ctx.diagnostic(NoObjectAsDefaultParameterDiagnostic::NonIdentifier(object_expr.span));
+    }
+}
+
+#[test]
+fn test() {
+    use crate::tester::Tester;
+
+    let pass = vec![
+        r#"const abc = {};"#,
+        r#"const abc = {foo: 123};"#,
+        r#"function abc(foo) {}"#,
+        r#"function abc(foo = null) {}"#,
+        r#"function abc(foo = undefined) {}"#,
+        r#"function abc(foo = 123) {}"#,
+        r#"function abc(foo = true) {}"#,
+        r#"function abc(foo = "bar") {}"#,
+        r#"function abc(foo = 123, bar = "foo") {}"#,
+        r#"function abc(foo = {}) {}"#,
+        r#"function abc({foo = 123} = {}) {}"#,
+        r#"(function abc() {})(foo = {a: 123})"#,
+        r#"const abc = foo => {};"#,
+        r#"const abc = (foo = null) => {};"#,
+        r#"const abc = (foo = undefined) => {};"#,
+        r#"const abc = (foo = 123) => {};"#,
+        r#"const abc = (foo = true) => {};"#,
+        r#"const abc = (foo = "bar") => {};"#,
+        r#"const abc = (foo = 123, bar = "foo") => {};"#,
+        r#"const abc = (foo = {}) => {};"#,
+        r#"const abc = ({a = true, b = "foo"}) => {};"#,
+        r#"const abc = function(foo = 123) {}"#,
+        r#"const {abc = {foo: 123}} = bar;"#,
+        r#"const {abc = {null: "baz"}} = bar;"#,
+        r#"const {abc = {foo: undefined}} = undefined;"#,
+        r#"const abc = ([{foo = false, bar = 123}]) => {};"#,
+        r#"const abc = ({foo = {a: 123}}) => {};"#,
+        r#"const abc = ([foo = {a: 123}]) => {};"#,
+        r#"const abc = ({foo: bar = {a: 123}}) => {};"#,
+        r#"const abc = () => (foo = {a: 123});"#,
+    ];
+
+    let fail = vec![
+        r#"function abc(foo = {a: 123}) {}"#,
+        r#"async function * abc(foo = {a: 123}) {}"#,
+        r#"function abc(foo = {a: false}) {}"#,
+        r#"function abc(foo = {a: "bar"}) {}"#,
+        r#"function abc(foo = {a: "bar", b: {c: true}}) {}"#,
+        r#"const abc = (foo = {a: false}) => {};"#,
+        r#"const abc = (foo = {a: 123, b: false}) => {};"#,
+        r#"const abc = (foo = {a: false, b: 1, c: "test", d: null}) => {};"#,
+        r#"const abc = function(foo = {a: 123}) {}"#,
+        r#"function abc(foo = {a: 123}) {}"#,
+        r#"const abc = (foo = {a: false}) => {};"#,
+        r#"function abc({a} = {a: 123}) {}"#,
+        r#"function abc([a] = {a: 123}) {}"#,
+    ];
+
+    Tester::new_without_config(NoObjectAsDefaultParameter::NAME, pass, fail).test_and_snapshot();
+}

crates/oxc_linter/src/snapshots/no_object_as_default_parameter.snap

@@ -0,0 +1,83 @@
+---
+source: crates/oxc_linter/src/tester.rs
+expression: no_object_as_default_parameter
+---
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc(foo = {a: 123}) {}
+   ·                    ────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ async function * abc(foo = {a: 123}) {}
+   ·                            ────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc(foo = {a: false}) {}
+   ·                    ──────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc(foo = {a: "bar"}) {}
+   ·                    ──────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc(foo = {a: "bar", b: {c: true}}) {}
+   ·                    ────────────────────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ const abc = (foo = {a: false}) => {};
+   ·                    ──────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ const abc = (foo = {a: 123, b: false}) => {};
+   ·                    ──────────────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ const abc = (foo = {a: false, b: 1, c: "test", d: null}) => {};
+   ·                    ────────────────────────────────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ const abc = function(foo = {a: 123}) {}
+   ·                            ────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc(foo = {a: 123}) {}
+   ·                    ────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default for parameter `foo`.
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ const abc = (foo = {a: false}) => {};
+   ·                    ──────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc({a} = {a: 123}) {}
+   ·                    ────────
+   ╰────
+
+  ⚠ eslint-plugin-unicorn(no-object-as-default-parameter): Do not use an object literal as default
+   ╭─[no_object_as_default_parameter.tsx:1:1]
+ 1 │ function abc([a] = {a: 123}) {}
+   ·                    ────────
+   ╰────
+
+