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[dotfiles/.git] / .config / coc / extensions / node_modules / coc-prettier / node_modules / eslint / lib / rules / no-duplicate-case.js
diff --git a/.config/coc/extensions/node_modules/coc-prettier/node_modules/eslint/lib/rules/no-duplicate-case.js b/.config/coc/extensions/node_modules/coc-prettier/node_modules/eslint/lib/rules/no-duplicate-case.js
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+/**
+ * @fileoverview Rule to disallow a duplicate case label.
+ * @author Dieter Oberkofler
+ * @author Burak Yigit Kaya
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const astUtils = require("./utils/ast-utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+    meta: {
+        type: "problem",
+
+        docs: {
+            description: "disallow duplicate case labels",
+            category: "Possible Errors",
+            recommended: true,
+            url: "https://eslint.org/docs/rules/no-duplicate-case"
+        },
+
+        schema: [],
+
+        messages: {
+            unexpected: "Duplicate case label."
+        }
+    },
+
+    create(context) {
+        const sourceCode = context.getSourceCode();
+
+        /**
+         * Determines whether the two given nodes are considered to be equal.
+         * @param {ASTNode} a First node.
+         * @param {ASTNode} b Second node.
+         * @returns {boolean} `true` if the nodes are considered to be equal.
+         */
+        function equal(a, b) {
+            if (a.type !== b.type) {
+                return false;
+            }
+
+            return astUtils.equalTokens(a, b, sourceCode);
+        }
+        return {
+            SwitchStatement(node) {
+                const previousTests = [];
+
+                for (const switchCase of node.cases) {
+                    if (switchCase.test) {
+                        const test = switchCase.test;
+
+                        if (previousTests.some(previousTest => equal(previousTest, test))) {
+                            context.report({ node: switchCase, messageId: "unexpected" });
+                        } else {
+                            previousTests.push(test);
+                        }
+                    }
+                }
+            }
+        };
+    }
+};