feat(js_analyze): implement noDivRegex

.changeset/fast-needles-hammer.md

@@ -0,0 +1,13 @@
+---
+"@biomejs/biome": patch
+---
+
+Added the nursery rule [`noDivRegex`](https://biomejs.dev/linter/rules/no-div-regex). Disallow equal signs explicitly at the beginning of regular expressions.
+
+**Invalid:**
+
+```js
+var f = function() {
+  return /=foo/;
+};
+```

crates/biome_js_analyze/src/lint/nursery.rs

@@ -7,6 +7,7 @@ pub mod no_ambiguous_anchor_text;
 pub mod no_before_interactive_script_outside_document;
 pub mod no_continue;
 pub mod no_deprecated_imports;
+pub mod no_div_regex;
 pub mod no_duplicate_enum_values;
 pub mod no_duplicated_spread_props;
 pub mod no_empty_source;
@@ -60,4 +61,4 @@ pub mod use_spread;
 pub mod use_vue_consistent_define_props_declaration;
 pub mod use_vue_define_macros_order;
 pub mod use_vue_multi_word_component_names;
-declare_lint_group! { pub Nursery { name : "nursery" , rules : [self :: no_ambiguous_anchor_text :: NoAmbiguousAnchorText , self :: no_before_interactive_script_outside_document :: NoBeforeInteractiveScriptOutsideDocument , self :: no_continue :: NoContinue , self :: no_deprecated_imports :: NoDeprecatedImports , self :: no_duplicate_enum_values :: NoDuplicateEnumValues , self :: no_duplicated_spread_props :: NoDuplicatedSpreadProps , self :: no_empty_source :: NoEmptySource , self :: no_equals_to_null :: NoEqualsToNull , self :: no_excessive_lines_per_file :: NoExcessiveLinesPerFile , self :: no_floating_promises :: NoFloatingPromises , self :: no_for_in :: NoForIn , self :: no_import_cycles :: NoImportCycles , self :: no_increment_decrement :: NoIncrementDecrement , self :: no_jsx_literals :: NoJsxLiterals , self :: no_jsx_props_bind :: NoJsxPropsBind , self :: no_leaked_render :: NoLeakedRender , self :: no_misused_promises :: NoMisusedPromises , self :: no_multi_assign :: NoMultiAssign , self :: no_multi_str :: NoMultiStr , self :: no_next_async_client_component :: NoNextAsyncClientComponent , self :: no_parameters_only_used_in_recursion :: NoParametersOnlyUsedInRecursion , self :: no_proto :: NoProto , self :: no_react_forward_ref :: NoReactForwardRef , self :: no_return_assign :: NoReturnAssign , self :: no_script_url :: NoScriptUrl , self :: no_shadow :: NoShadow , self :: no_sync_scripts :: NoSyncScripts , self :: no_ternary :: NoTernary , self :: no_undeclared_env_vars :: NoUndeclaredEnvVars , self :: no_unknown_attribute :: NoUnknownAttribute , self :: no_unnecessary_conditions :: NoUnnecessaryConditions , self :: no_unresolved_imports :: NoUnresolvedImports , self :: no_unused_expressions :: NoUnusedExpressions , self :: no_useless_catch_binding :: NoUselessCatchBinding , self :: no_useless_undefined :: NoUselessUndefined , self :: no_vue_data_object_declaration :: NoVueDataObjectDeclaration , self :: no_vue_duplicate_keys :: NoVueDuplicateKeys , self :: no_vue_reserved_keys :: NoVueReservedKeys , self :: no_vue_reserved_props :: NoVueReservedProps , self :: no_vue_setup_props_reactivity_loss :: NoVueSetupPropsReactivityLoss , self :: use_array_sort_compare :: UseArraySortCompare , self :: use_await_thenable :: UseAwaitThenable , self :: use_consistent_arrow_return :: UseConsistentArrowReturn , self :: use_destructuring :: UseDestructuring , self :: use_error_cause :: UseErrorCause , self :: use_exhaustive_switch_cases :: UseExhaustiveSwitchCases , self :: use_explicit_type :: UseExplicitType , self :: use_find :: UseFind , self :: use_max_params :: UseMaxParams , self :: use_qwik_method_usage :: UseQwikMethodUsage , self :: use_qwik_valid_lexical_scope :: UseQwikValidLexicalScope , self :: use_regexp_exec :: UseRegexpExec , self :: use_sorted_classes :: UseSortedClasses , self :: use_spread :: UseSpread , self :: use_vue_consistent_define_props_declaration :: UseVueConsistentDefinePropsDeclaration , self :: use_vue_define_macros_order :: UseVueDefineMacrosOrder , self :: use_vue_multi_word_component_names :: UseVueMultiWordComponentNames ,] } }
+declare_lint_group! { pub Nursery { name : "nursery" , rules : [self :: no_ambiguous_anchor_text :: NoAmbiguousAnchorText , self :: no_before_interactive_script_outside_document :: NoBeforeInteractiveScriptOutsideDocument , self :: no_continue :: NoContinue , self :: no_deprecated_imports :: NoDeprecatedImports , self :: no_div_regex :: NoDivRegex , self :: no_duplicate_enum_values :: NoDuplicateEnumValues , self :: no_duplicated_spread_props :: NoDuplicatedSpreadProps , self :: no_empty_source :: NoEmptySource , self :: no_equals_to_null :: NoEqualsToNull , self :: no_excessive_lines_per_file :: NoExcessiveLinesPerFile , self :: no_floating_promises :: NoFloatingPromises , self :: no_for_in :: NoForIn , self :: no_import_cycles :: NoImportCycles , self :: no_increment_decrement :: NoIncrementDecrement , self :: no_jsx_literals :: NoJsxLiterals , self :: no_jsx_props_bind :: NoJsxPropsBind , self :: no_leaked_render :: NoLeakedRender , self :: no_misused_promises :: NoMisusedPromises , self :: no_multi_assign :: NoMultiAssign , self :: no_multi_str :: NoMultiStr , self :: no_next_async_client_component :: NoNextAsyncClientComponent , self :: no_parameters_only_used_in_recursion :: NoParametersOnlyUsedInRecursion , self :: no_proto :: NoProto , self :: no_react_forward_ref :: NoReactForwardRef , self :: no_return_assign :: NoReturnAssign , self :: no_script_url :: NoScriptUrl , self :: no_shadow :: NoShadow , self :: no_sync_scripts :: NoSyncScripts , self :: no_ternary :: NoTernary , self :: no_undeclared_env_vars :: NoUndeclaredEnvVars , self :: no_unknown_attribute :: NoUnknownAttribute , self :: no_unnecessary_conditions :: NoUnnecessaryConditions , self :: no_unresolved_imports :: NoUnresolvedImports , self :: no_unused_expressions :: NoUnusedExpressions , self :: no_useless_catch_binding :: NoUselessCatchBinding , self :: no_useless_undefined :: NoUselessUndefined , self :: no_vue_data_object_declaration :: NoVueDataObjectDeclaration , self :: no_vue_duplicate_keys :: NoVueDuplicateKeys , self :: no_vue_reserved_keys :: NoVueReservedKeys , self :: no_vue_reserved_props :: NoVueReservedProps , self :: no_vue_setup_props_reactivity_loss :: NoVueSetupPropsReactivityLoss , self :: use_array_sort_compare :: UseArraySortCompare , self :: use_await_thenable :: UseAwaitThenable , self :: use_consistent_arrow_return :: UseConsistentArrowReturn , self :: use_destructuring :: UseDestructuring , self :: use_error_cause :: UseErrorCause , self :: use_exhaustive_switch_cases :: UseExhaustiveSwitchCases , self :: use_explicit_type :: UseExplicitType , self :: use_find :: UseFind , self :: use_max_params :: UseMaxParams , self :: use_qwik_method_usage :: UseQwikMethodUsage , self :: use_qwik_valid_lexical_scope :: UseQwikValidLexicalScope , self :: use_regexp_exec :: UseRegexpExec , self :: use_sorted_classes :: UseSortedClasses , self :: use_spread :: UseSpread , self :: use_vue_consistent_define_props_declaration :: UseVueConsistentDefinePropsDeclaration , self :: use_vue_define_macros_order :: UseVueDefineMacrosOrder , self :: use_vue_multi_word_component_names :: UseVueMultiWordComponentNames ,] } }

crates/biome_js_analyze/src/lint/nursery/no_div_regex.rs

@@ -0,0 +1,109 @@
+use biome_analyze::{
+    Ast, FixKind, Rule, RuleAction, RuleDiagnostic, RuleSource, context::RuleContext,
+    declare_lint_rule,
+};
+use biome_console::markup;
+use biome_js_syntax::{JsRegexLiteralExpression, JsSyntaxKind, JsSyntaxToken};
+use biome_rowan::{AstNode, BatchMutationExt};
+use biome_rule_options::no_div_regex::NoDivRegexOptions;
+
+use crate::JsRuleAction;
+
+declare_lint_rule! {
+    /// Disallow equal signs explicitly at the beginning of regular expressions.
+    ///
+    /// This rule forbids equal signs (`=`) after the slash (`/`) at the beginning of a regular expression literal,
+    /// because the characters `/=` can be confused with a division assignment operator.
+    ///
+    /// ## Examples
+    ///
+    /// ### Invalid
+    ///
+    /// ```js,expect_diagnostic
+    /// function bar() {
+    ///   return /=foo/;
+    /// }
+    /// ```
+    ///
+    /// ### Valid
+    ///
+    /// ```js
+    /// function bar() {
+    ///   return /[=]foo/;
+    /// }
+    /// ```
+    ///
+    pub NoDivRegex {
+        version: "next",
+        name: "noDivRegex",
+        language: "js",
+        recommended: false,
+        sources: &[RuleSource::Eslint("no-div-regex").same()],
+        fix_kind: FixKind::Safe,
+    }
+}
+
+impl Rule for NoDivRegex {
+    type Query = Ast<JsRegexLiteralExpression>;
+    type State = ();
+    type Signals = Option<Self::State>;
+    type Options = NoDivRegexOptions;
+
+    fn run(ctx: &RuleContext<Self>) -> Self::Signals {
+        let node = ctx.query();
+
+        let value_token = node.value_token().ok()?;
+        let text = value_token.text_trimmed();
+
+        if let Some(first_char) = text.chars().nth(1)
+            && first_char == '='
+        {
+            return Some(());
+        }
+
+        None
+    }
+
+    fn diagnostic(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<RuleDiagnostic> {
+        let node = ctx.query();
+        Some(
+            RuleDiagnostic::new(
+                rule_category!(),
+                node.range(),
+                markup! {
+                    "A regular expression literal can be confused with '/='."
+                },
+            )
+            .note(markup! {
+                "The characters `/=` can be confused with a division assignment operator. Replace with `[=]` to prevent confusion."
+            }),
+        )
+    }
+
+    fn action(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<JsRuleAction> {
+        let node = ctx.query();
+        let mut mutation = ctx.root().begin();
+
+        let text = node.to_trimmed_string();
+        let new_text = format!("/[=]{}", &text[2..]);
+
+        let new_node = node.clone().with_value_token(JsSyntaxToken::new_detached(
+            JsSyntaxKind::JS_REGEX_LITERAL,
+            new_text.as_str(),
+            [],
+            [],
+        ));
+
+        mutation.replace_node(node.clone(), new_node);
+
+        Some(RuleAction::new(
+            ctx.metadata().action_category(ctx.category(), ctx.group()),
+            ctx.metadata().applicability(),
+            markup! {
+                "Replace with `[=]`."
+            }
+            .to_owned(),
+            mutation,
+        ))
+    }
+}

crates/biome_js_analyze/tests/specs/nursery/noDivRegex/invalid.js

@@ -0,0 +1,2 @@
+/* should generate diagnostics */
+var f = function() { return /=foo/; };

crates/biome_js_analyze/tests/specs/nursery/noDivRegex/invalid.js.snap

@@ -0,0 +1,32 @@
+---
+source: crates/biome_js_analyze/tests/spec_tests.rs
+expression: invalid.js
+---
+# Input
+```js
+/* should generate diagnostics */
+var f = function() { return /=foo/; };
+
+```
+
+# Diagnostics
+```
+invalid.js:2:29 lint/nursery/noDivRegex  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  i A regular expression literal can be confused with '/='.
+
+    1 │ /* should generate diagnostics */
+  > 2 │ var f = function() { return /=foo/; };
+      │                             ^^^^^^
+    3 │ 
+
+  i The characters `/=` can be confused with a division assignment operator. Replace with `[=]` to prevent confusion.
+
+  i This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
+
+  i Safe fix: Replace with `[=]`.
+
+    2 │ var·f·=·function()·{·return·/[=]foo/;·};
+      │                              + +        
+
+```

crates/biome_js_analyze/tests/specs/nursery/noDivRegex/valid.js

@@ -0,0 +1,4 @@
+/* should not generate diagnostics */
+var f = function() { return /foo/ig.test('bar'); };
+
+var f = function() { return /\\=foo/; };

crates/biome_js_analyze/tests/specs/nursery/noDivRegex/valid.js.snap

@@ -0,0 +1,12 @@
+---
+source: crates/biome_js_analyze/tests/spec_tests.rs
+expression: valid.js
+---
+# Input
+```js
+/* should not generate diagnostics */
+var f = function() { return /foo/ig.test('bar'); };
+
+var f = function() { return /\\=foo/; };
+
+```

crates/biome_rule_options/src/lib.rs

@@ -48,6 +48,7 @@ pub mod no_delete;
 pub mod no_deprecated_imports;
 pub mod no_descending_specificity;
 pub mod no_distracting_elements;
+pub mod no_div_regex;
 pub mod no_document_cookie;
 pub mod no_document_import_in_page;
 pub mod no_done_callback;

crates/biome_rule_options/src/no_div_regex.rs

@@ -0,0 +1,6 @@
+use biome_deserialize_macros::{Deserializable, Merge};
+use serde::{Deserialize, Serialize};
+#[derive(Default, Clone, Debug, Deserialize, Deserializable, Merge, Eq, PartialEq, Serialize)]
+#[cfg_attr(feature = "schema", derive(schemars::JsonSchema))]
+#[serde(rename_all = "camelCase", deny_unknown_fields, default)]
+pub struct NoDivRegexOptions {}