Repository: eslint/eslint
Pull request #15325 (2021-11-17 15:37:08)

feat: update prefer-const for class static blocks
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#### What is the purpose of this pull request? (put an "X" next to an item)

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[ ] Documentation update
[ ] Bug fix ([template](https://raw.githubusercontent.com/eslint/eslint/HEAD/templates/bug-report.md))
[ ] New rule ([template](https://raw.githubusercontent.com/eslint/eslint/HEAD/templates/rule-proposal.md))
[x] Changes an existing rule ([template](https://raw.githubusercontent.com/eslint/eslint/HEAD/templates/rule-change-proposal.md))
[ ] Add autofixing to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

Refs #15016, fixes `prefer-const`

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#### What changes did you make? (Give an overview)

This PR fixes false negatives of the `prefer-const` rule at the top level of class static blocks.

Example of a false negative:

```js
/* eslint prefer-const: "error" */

class C {
    static {
        let a;
        a = 0; 
    }
}
```

#### Is there anything you'd like reviewers to focus on?



Patch:
diff --git a/docs/developer-guide/code-path-analysis.md b/docs/developer-guide/code-path-analysis.md
index 3507ff641..f22eb8f34 100644
--- a/docs/developer-guide/code-path-analysis.md
+++ b/docs/developer-guide/code-path-analysis.md
@@ -27,7 +27,7 @@ This has references of both the initial segment and the final segments of a code
 `CodePath` has the following properties:
 
 * `id` (`string`) - A unique string. Respective rules can use `id` to save additional information for each code path.
-* `origin` (`string`) - The reason that the code path was started. May be `"program"`, `"function"`, or `"class-field-initializer"`.
+* `origin` (`string`) - The reason that the code path was started. May be `"program"`, `"function"`, `"class-field-initializer"`, or `"class-static-block"`.
 * `initialSegment` (`CodePathSegment`) - The initial segment of this code path.
 * `finalSegments` (`CodePathSegment[]`) - The final segments which includes both returned and thrown.
 * `returnedSegments` (`CodePathSegment[]`) - The final segments which includes only returned.
diff --git a/docs/rules/prefer-const.md b/docs/rules/prefer-const.md
index 3e5a5d0c3..3cdba9e4d 100644
--- a/docs/rules/prefer-const.md
+++ b/docs/rules/prefer-const.md
@@ -12,7 +12,6 @@ Examples of **incorrect** code for this rule:
 
 ```js
 /*eslint prefer-const: "error"*/
-/*eslint-env es6*/
 
 // it's initialized and never reassigned.
 let a = 3;
@@ -22,6 +21,14 @@ let a;
 a = 0;
 console.log(a);
 
+class C {
+    static {
+        let a;
+        a = 0;
+        console.log(a);
+    }
+}
+
 // `i` is redefined (not reassigned) on each loop step.
 for (let i in [1, 2, 3]) {
     console.log(i);
@@ -37,7 +44,6 @@ Examples of **correct** code for this rule:
 
 ```js
 /*eslint prefer-const: "error"*/
-/*eslint-env es6*/
 
 // using const.
 const a = 0;
@@ -59,6 +65,15 @@ if (true) {
 }
 console.log(a);
 
+// it's initialized in a different scope.
+let a;
+class C {
+    #x;
+    static {
+        a = obj => obj.#x;
+    }
+}
+
 // it's initialized at a place that we cannot write a variable declaration.
 let a;
 if (true) a = 0;
diff --git a/lib/linter/code-path-analysis/code-path-analyzer.js b/lib/linter/code-path-analysis/code-path-analyzer.js
index d66c2f1be..2dcc27348 100644
--- a/lib/linter/code-path-analysis/code-path-analyzer.js
+++ b/lib/linter/code-path-analysis/code-path-analyzer.js
@@ -461,6 +461,10 @@ function processCodePathToEnter(analyzer, node) {
             startCodePath("function");
             break;
 
+        case "StaticBlock":
+            startCodePath("class-static-block");
+            break;
+
         case "ChainExpression":
             state.pushChainContext();
             break;
@@ -706,7 +710,8 @@ function postprocess(analyzer, node) {
         case "Program":
         case "FunctionDeclaration":
         case "FunctionExpression":
-        case "ArrowFunctionExpression": {
+        case "ArrowFunctionExpression":
+        case "StaticBlock": {
             endCodePath();
             break;
         }
diff --git a/lib/linter/code-path-analysis/code-path.js b/lib/linter/code-path-analysis/code-path.js
index f225c09a1..0e6662770 100644
--- a/lib/linter/code-path-analysis/code-path.js
+++ b/lib/linter/code-path-analysis/code-path.js
@@ -40,7 +40,7 @@ class CodePath {
 
         /**
          * The reason that this code path was started. May be "program",
-         * "function", or "class-field-initializer".
+         * "function", "class-field-initializer", or "class-static-block".
          * @type {string}
          */
         this.origin = origin;
diff --git a/lib/rules/prefer-const.js b/lib/rules/prefer-const.js
index b44bd7592..38ec973fc 100644
--- a/lib/rules/prefer-const.js
+++ b/lib/rules/prefer-const.js
@@ -17,7 +17,7 @@ const astUtils = require("./utils/ast-utils");
 //------------------------------------------------------------------------------
 
 const PATTERN_TYPE = /^(?:.+?Pattern|RestElement|SpreadProperty|ExperimentalRestProperty|Property)$/u;
-const DECLARATION_HOST_TYPE = /^(?:Program|BlockStatement|SwitchCase)$/u;
+const DECLARATION_HOST_TYPE = /^(?:Program|BlockStatement|StaticBlock|SwitchCase)$/u;
 const DESTRUCTURING_HOST_TYPE = /^(?:VariableDeclarator|AssignmentExpression)$/u;
 
 /**


Test patch:
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--between-fields.js b/tests/fixtures/code-path-analysis/class-static-blocks--between-fields.js
new file mode 100644
index 000000000..9bf8edfef
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--between-fields.js
@@ -0,0 +1,65 @@
+/*expected
+initial->s2_1->s2_2->s2_3;
+s2_1->s2_3->final;
+*/
+/*expected
+initial->s3_1->s3_2->s3_3->s3_4;
+s3_1->s3_4;
+s3_2->s3_4->final;
+*/
+/*expected
+initial->s4_1->s4_2->s4_3->s4_4->s4_5;
+s4_1->s4_5;
+s4_2->s4_5;
+s4_3->s4_5->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { bar = a || b; static { x || y || z } baz = p || q || r || s; }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="LogicalExpression:enter\nIdentifier (a)"];
+    s2_2[label="Identifier (b)"];
+    s2_3[label="LogicalExpression:exit"];
+    initial->s2_1->s2_2->s2_3;
+    s2_1->s2_3->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s3_1[label="StaticBlock:enter\nExpressionStatement:enter\nLogicalExpression:enter\nLogicalExpression:enter\nIdentifier (x)"];
+    s3_2[label="Identifier (y)\nLogicalExpression:exit"];
+    s3_3[label="Identifier (z)"];
+    s3_4[label="LogicalExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s3_1->s3_2->s3_3->s3_4;
+    s3_1->s3_4;
+    s3_2->s3_4->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s4_1[label="LogicalExpression:enter\nLogicalExpression:enter\nLogicalExpression:enter\nIdentifier (p)"];
+    s4_2[label="Identifier (q)\nLogicalExpression:exit"];
+    s4_3[label="Identifier (r)\nLogicalExpression:exit"];
+    s4_4[label="Identifier (s)"];
+    s4_5[label="LogicalExpression:exit"];
+    initial->s4_1->s4_2->s4_3->s4_4->s4_5;
+    s4_1->s4_5;
+    s4_2->s4_5;
+    s4_3->s4_5->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nPropertyDefinition:enter\nIdentifier (bar)\nLogicalExpression\nPropertyDefinition:exit\nStaticBlock\nPropertyDefinition:enter\nIdentifier (baz)\nLogicalExpression\nPropertyDefinition:exit\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--between-methods.js b/tests/fixtures/code-path-analysis/class-static-blocks--between-methods.js
new file mode 100644
index 000000000..a6de6909a
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--between-methods.js
@@ -0,0 +1,65 @@
+/*expected
+initial->s2_1->s2_2->s2_3;
+s2_1->s2_3->final;
+*/
+/*expected
+initial->s3_1->s3_2->s3_3->s3_4;
+s3_1->s3_4;
+s3_2->s3_4->final;
+*/
+/*expected
+initial->s4_1->s4_2->s4_3->s4_4->s4_5;
+s4_1->s4_5;
+s4_2->s4_5;
+s4_3->s4_5->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { bar () { a || b } static { x || y || z } baz() { p || q || r || s } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="FunctionExpression:enter\nBlockStatement:enter\nExpressionStatement:enter\nLogicalExpression:enter\nIdentifier (a)"];
+    s2_2[label="Identifier (b)"];
+    s2_3[label="LogicalExpression:exit\nExpressionStatement:exit\nBlockStatement:exit\nFunctionExpression:exit"];
+    initial->s2_1->s2_2->s2_3;
+    s2_1->s2_3->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s3_1[label="StaticBlock:enter\nExpressionStatement:enter\nLogicalExpression:enter\nLogicalExpression:enter\nIdentifier (x)"];
+    s3_2[label="Identifier (y)\nLogicalExpression:exit"];
+    s3_3[label="Identifier (z)"];
+    s3_4[label="LogicalExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s3_1->s3_2->s3_3->s3_4;
+    s3_1->s3_4;
+    s3_2->s3_4->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s4_1[label="FunctionExpression:enter\nBlockStatement:enter\nExpressionStatement:enter\nLogicalExpression:enter\nLogicalExpression:enter\nLogicalExpression:enter\nIdentifier (p)"];
+    s4_2[label="Identifier (q)\nLogicalExpression:exit"];
+    s4_3[label="Identifier (r)\nLogicalExpression:exit"];
+    s4_4[label="Identifier (s)"];
+    s4_5[label="LogicalExpression:exit\nExpressionStatement:exit\nBlockStatement:exit\nFunctionExpression:exit"];
+    initial->s4_1->s4_2->s4_3->s4_4->s4_5;
+    s4_1->s4_5;
+    s4_2->s4_5;
+    s4_3->s4_5->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nMethodDefinition:enter\nIdentifier (bar)\nFunctionExpression\nMethodDefinition:exit\nStaticBlock\nMethodDefinition:enter\nIdentifier (baz)\nFunctionExpression\nMethodDefinition:exit\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--conditional.js b/tests/fixtures/code-path-analysis/class-static-blocks--conditional.js
new file mode 100644
index 000000000..bcdb4a7ec
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--conditional.js
@@ -0,0 +1,29 @@
+/*expected
+initial->s2_1->s2_2->s2_4;
+s2_1->s2_3->s2_4->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { this.bar = a ? b : c; } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (bar)\nMemberExpression:exit\nConditionalExpression:enter\nIdentifier (a)"];
+    s2_2[label="Identifier (b)"];
+    s2_4[label="ConditionalExpression:exit\nAssignmentExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    s2_3[label="Identifier (c)"];
+    initial->s2_1->s2_2->s2_4;
+    s2_1->s2_3->s2_4->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--empty.js b/tests/fixtures/code-path-analysis/class-static-blocks--empty.js
new file mode 100644
index 000000000..40a1e71ae
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--empty.js
@@ -0,0 +1,24 @@
+/*expected
+initial->s2_1->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static {} }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock"];
+    initial->s2_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--function-inside.js b/tests/fixtures/code-path-analysis/class-static-blocks--function-inside.js
new file mode 100644
index 000000000..49df347f0
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--function-inside.js
@@ -0,0 +1,34 @@
+/*expected
+initial->s3_1->final;
+*/
+/*expected
+initial->s2_1->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { (p) => {} } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s3_1[label="ArrowFunctionExpression:enter\nIdentifier (p)\nBlockStatement\nArrowFunctionExpression:exit"];
+    initial->s3_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nExpressionStatement:enter\nArrowFunctionExpression\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s2_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--if-else.js b/tests/fixtures/code-path-analysis/class-static-blocks--if-else.js
new file mode 100644
index 000000000..7b4a542bc
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--if-else.js
@@ -0,0 +1,29 @@
+/*expected
+initial->s2_1->s2_2->s2_4;
+s2_1->s2_3->s2_4->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { if (bar) { this.baz = 1; } else { this.qux = 2; } } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nIfStatement:enter\nIdentifier (bar)"];
+    s2_2[label="BlockStatement:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (baz)\nMemberExpression:exit\nLiteral (1)\nAssignmentExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    s2_4[label="IfStatement:exit\nStaticBlock:exit"];
+    s2_3[label="BlockStatement:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (qux)\nMemberExpression:exit\nLiteral (2)\nAssignmentExpression:exit\nExpressionStatement:exit\nBlockStatement:exit"];
+    initial->s2_1->s2_2->s2_4;
+    s2_1->s2_3->s2_4->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--multiple-1.js b/tests/fixtures/code-path-analysis/class-static-blocks--multiple-1.js
new file mode 100644
index 000000000..67365fb2f
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--multiple-1.js
@@ -0,0 +1,34 @@
+/*expected
+initial->s2_1->final;
+*/
+/*expected
+initial->s3_1->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { this.bar = 1; } static { this.baz = 2; } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (bar)\nMemberExpression:exit\nLiteral (1)\nAssignmentExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s2_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s3_1[label="StaticBlock:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (baz)\nMemberExpression:exit\nLiteral (2)\nAssignmentExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s3_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--multiple-2.js b/tests/fixtures/code-path-analysis/class-static-blocks--multiple-2.js
new file mode 100644
index 000000000..218d18a78
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--multiple-2.js
@@ -0,0 +1,45 @@
+/*expected
+initial->s2_1->s2_2->s2_3->s2_4;
+s2_1->s2_4;
+s2_2->s2_4->final;
+*/
+/*expected
+initial->s3_1->s3_2->s3_3;
+s3_1->s3_3->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { x || y || z } static { p || q } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nExpressionStatement:enter\nLogicalExpression:enter\nLogicalExpression:enter\nIdentifier (x)"];
+    s2_2[label="Identifier (y)\nLogicalExpression:exit"];
+    s2_3[label="Identifier (z)"];
+    s2_4[label="LogicalExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s2_1->s2_2->s2_3->s2_4;
+    s2_1->s2_4;
+    s2_2->s2_4->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s3_1[label="StaticBlock:enter\nExpressionStatement:enter\nLogicalExpression:enter\nIdentifier (p)"];
+    s3_2[label="Identifier (q)"];
+    s3_3[label="LogicalExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s3_1->s3_2->s3_3;
+    s3_1->s3_3->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/fixtures/code-path-analysis/class-static-blocks--simple.js b/tests/fixtures/code-path-analysis/class-static-blocks--simple.js
new file mode 100644
index 000000000..06bb73787
--- /dev/null
+++ b/tests/fixtures/code-path-analysis/class-static-blocks--simple.js
@@ -0,0 +1,24 @@
+/*expected
+initial->s2_1->final;
+*/
+/*expected
+initial->s1_1->final;
+*/
+class Foo { static { this.bar = baz; } }
+
+/*DOT
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s2_1[label="StaticBlock:enter\nExpressionStatement:enter\nAssignmentExpression:enter\nMemberExpression:enter\nThisExpression\nIdentifier (bar)\nMemberExpression:exit\nIdentifier (baz)\nAssignmentExpression:exit\nExpressionStatement:exit\nStaticBlock:exit"];
+    initial->s2_1->final;
+}
+digraph {
+    node[shape=box,style="rounded,filled",fillcolor=white];
+    initial[label="",shape=circle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    final[label="",shape=doublecircle,style=filled,fillcolor=black,width=0.25,height=0.25];
+    s1_1[label="Program:enter\nClassDeclaration:enter\nIdentifier (Foo)\nClassBody:enter\nStaticBlock\nClassBody:exit\nClassDeclaration:exit\nProgram:exit"];
+    initial->s1_1->final;
+}
+*/
diff --git a/tests/lib/linter/code-path-analysis/code-path.js b/tests/lib/linter/code-path-analysis/code-path.js
index 42a63a280..760d5b399 100644
--- a/tests/lib/linter/code-path-analysis/code-path.js
+++ b/tests/lib/linter/code-path-analysis/code-path.js
@@ -106,6 +106,12 @@ describe("CodePathAnalyzer", () => {
 
             assert.strictEqual(codePath.origin, "class-field-initializer");
         });
+
+        it("should be 'class-static-block' when code path starts inside a class static block", () => {
+            const codePath = parseCodePaths("class Foo { static { this.a=1; } }")[1];
+
+            assert.strictEqual(codePath.origin, "class-static-block");
+        });
     });
 
     describe(".traverseSegments()", () => {
diff --git a/tests/lib/rules/prefer-const.js b/tests/lib/rules/prefer-const.js
index c591d2365..0a44b0bd0 100644
--- a/tests/lib/rules/prefer-const.js
+++ b/tests/lib/rules/prefer-const.js
@@ -173,7 +173,56 @@ ruleTester.run("prefer-const", rule, {
 
         // https://github.com/eslint/eslint/issues/10520
         "const x = [1,2]; let y; [,y] = x; y = 0;",
-        "const x = [1,2,3]; let y, z; [y,,z] = x; y = 0; z = 0;"
+        "const x = [1,2,3]; let y, z; [y,,z] = x; y = 0; z = 0;",
+
+        {
+            code: "class C { static { let a = 1; a = 2; } }",
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "class C { static { let a; a = 1; a = 2; } }",
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "let a; class C { static { a = 1; } }",
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "class C { static { let a; if (foo) { a = 1; } } }",
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "class C { static { let a; if (foo) a = 1; } }",
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "class C { static { let a, b; if (foo) { ({ a, b } = foo); } } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" },
+                { messageId: "useConst", data: { name: "b" }, type: "Identifier" }
+            ]
+        },
+        {
+            code: "class C { static { let a, b; if (foo) ({ a, b } = foo); } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" },
+                { messageId: "useConst", data: { name: "b" }, type: "Identifier" }
+            ]
+        },
+        {
+            code: "class C { static { a; } } let a = 1; ",
+            options: [{ ignoreReadBeforeAssign: true }],
+            parserOptions: { ecmaVersion: 2022 }
+        },
+        {
+            code: "class C { static { () => a; let a = 1; } };",
+            options: [{ ignoreReadBeforeAssign: true }],
+            parserOptions: { ecmaVersion: 2022 }
+        }
     ],
     invalid: [
         {
@@ -555,6 +604,86 @@ ruleTester.run("prefer-const", rule, {
             code: "/*eslint no-undef-init:error*/ let foo = undefined;",
             output: "/*eslint no-undef-init:error*/ const foo = undefined;",
             errors: 2
+        },
+
+        {
+            code: "let a = 1; class C { static { a; } }",
+            output: "const a = 1; class C { static { a; } }",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+
+            // this is a TDZ error with either `let` or `const`, but that isn't a concern of this rule
+            code: "class C { static { a; } } let a = 1;",
+            output: "class C { static { a; } } const a = 1;",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+            code: "class C { static { let a = 1; } }",
+            output: "class C { static { const a = 1; } }",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+            code: "class C { static { if (foo) { let a = 1; } } }",
+            output: "class C { static { if (foo) { const a = 1; } } }",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+            code: "class C { static { let a = 1; if (foo) { a; } } }",
+            output: "class C { static { const a = 1; if (foo) { a; } } }",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+            code: "class C { static { if (foo) { let a; a = 1; } } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier" }]
+        },
+        {
+            code: "class C { static { let a; a = 1; } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [{ messageId: "useConst", data: { name: "a" }, type: "Identifier", column: 27 }]
+        },
+        {
+            code: "class C { static { let { a, b } = foo; } }",
+            output: "class C { static { const { a, b } = foo; } }",
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" },
+                { messageId: "useConst", data: { name: "b" }, type: "Identifier" }
+            ]
+        },
+        {
+            code: "class C { static { let a, b; ({ a, b } = foo); } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" },
+                { messageId: "useConst", data: { name: "b" }, type: "Identifier" }
+            ]
+        },
+        {
+            code: "class C { static { let a; let b; ({ a, b } = foo); } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" },
+                { messageId: "useConst", data: { name: "b" }, type: "Identifier" }
+            ]
+        },
+        {
+            code: "class C { static { let a; a = 0; console.log(a); } }",
+            output: null,
+            parserOptions: { ecmaVersion: 2022 },
+            errors: [
+                { messageId: "useConst", data: { name: "a" }, type: "Identifier" }
+            ]
         }
     ]
 });