handle RegExp calls with regex patterns

eslint · Feb 25, 2024 · 6792594 · 6792594
1 parent 072f256
commit 6792594
Show file tree

Hide file tree

Showing 2 changed files with 109 additions and 9 deletions.
diff --git a/lib/rules/no-misleading-character-class.js b/lib/rules/no-misleading-character-class.js
@@ -3,7 +3,14 @@
  */
 "use strict";
 
-const { CALL, CONSTRUCT, ReferenceTracker, getStringIfConstant } = require("@eslint-community/eslint-utils");
+const { isRegExp } = require("node:util/types");
+const {
+    CALL,
+    CONSTRUCT,
+    ReferenceTracker,
+    getStaticValue,
+    getStringIfConstant
+} = require("@eslint-community/eslint-utils");
 const { RegExpParser, visitRegExpAST } = require("@eslint-community/regexpp");
 const { isCombiningCharacter, isEmojiModifier, isRegionalIndicatorSymbol, isSurrogatePair } = require("./utils/unicode");
 const astUtils = require("./utils/ast-utils.js");
@@ -226,6 +233,7 @@ module.exports = {
     create(context) {
         const sourceCode = context.sourceCode;
         const parser = new RegExpParser();
+        const checkedPatternNodes = new Set();
 
         /**
          * Verify a given regular expression.
@@ -342,6 +350,9 @@ module.exports = {
 
         return {
             "Literal[regex]"(node) {
+                if (checkedPatternNodes.has(node)) {
+                    return;
+                }
                 verify(node, node.regex.pattern, node.regex.flags, fixer => {
                     if (!isValidWithUnicodeFlag(context.languageOptions.ecmaVersion, node.regex.pattern)) {
                         return null;
@@ -364,16 +375,28 @@ module.exports = {
                 })) {
                     let pattern, flags;
                     const [patternNode, flagsNode] = refNode.arguments;
+                    const evaluatedPattern = getStaticValue(patternNode, scope);
 
-                    if (patternNode.type === "Literal" && patternNode.regex) {
-                        pattern = patternNode.regex.pattern;
-                        flags = flagsNode ? getStringIfConstant(flagsNode, scope) : patternNode.regex.flags;
+                    if (!evaluatedPattern) {
+                        continue;
+                    }
+                    if (flagsNode) {
+                        if (isRegExp(evaluatedPattern.value)) {
+                            pattern = evaluatedPattern.value.source;
+                            checkedPatternNodes.add(patternNode);
+                        } else {
+                            pattern = String(evaluatedPattern.value);
+                        }
+                        flags = getStringIfConstant(flagsNode, scope);
                     } else {
-                        pattern = getStringIfConstant(patternNode, scope);
-                        flags = flagsNode ? getStringIfConstant(flagsNode, scope) : "";
+                        if (isRegExp(evaluatedPattern.value)) {
+                            continue;
+                        }
+                        pattern = String(evaluatedPattern.value);
+                        flags = "";
                     }
 
-                    if (typeof pattern === "string" && typeof flags === "string") {
+                    if (typeof flags === "string") {
                         verify(patternNode, pattern, flags, fixer => {
 
                             if (!isValidWithUnicodeFlag(context.languageOptions.ecmaVersion, pattern)) {

diff --git a/tests/lib/rules/no-misleading-character-class.js b/tests/lib/rules/no-misleading-character-class.js
@@ -41,6 +41,11 @@ ruleTester.run("no-misleading-character-class", rule, {
         "var r = /[JP]/",
         "var r = /👨‍👩‍👦/",
         "var r = RegExp(/[👍]/u)",
+        "const regex = /[👍]/u; new RegExp(regex);",
+        {
+            code: "new RegExp('[👍]')",
+            languageOptions: { globals: { RegExp: "off" } }
+        },
 
         // Ignore solo lead/tail surrogate.
         "var r = /[\\uD83D]/",
@@ -80,6 +85,9 @@ ruleTester.run("no-misleading-character-class", rule, {
         "var r = new RegExp('[🇯🇵]', `${foo}`)",
         String.raw`var r = new RegExp("[👍]", flags)`,
 
+        // don't report on spread arguments
+        "const args = ['[👍]', 'i']; new RegExp(...args);",
+
         // ES2024
         { code: "var r = /[👍]/v", languageOptions: { ecmaVersion: 2024 } },
         { code: String.raw`var r = /^[\q{👶🏻}]$/v`, languageOptions: { ecmaVersion: 2024 } },
@@ -1351,14 +1359,83 @@ ruleTester.run("no-misleading-character-class", rule, {
             }]
         },
 
-        // second argument in RegExp should override flags in regexp literal
+        // second argument in RegExp should override flags in regex literal
         {
             code: "RegExp(/[a👍z]/u, '');",
             errors: [{
                 column: 11,
                 endColumn: 13,
                 messageId: "surrogatePairWithoutUFlag",
-                suggestions: [{ messageId: "suggestUnicodeFlag", output: "RegExp(/[a👍z]/u, 'u');" }]
+                suggestions: [{
+                    messageId: "suggestUnicodeFlag",
+                    output: "RegExp(/[a👍z]/u, 'u');"
+                }]
+            }]
+        },
+        {
+            code: "const pattern = /[👍]/u; RegExp(pattern, '');",
+            errors: [{
+                column: 33,
+                endColumn: 40,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{
+                    messageId: "suggestUnicodeFlag",
+                    output: "const pattern = /[👍]/u; RegExp(pattern, 'u');"
+                }]
+            }]
+        },
+        {
+            code: "const pattern = /[👍]/g; RegExp(pattern, 'i');",
+            errors: [{
+                column: 19,
+                endColumn: 21,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{
+                    messageId: "suggestUnicodeFlag",
+                    output: "const pattern = /[👍]/gu; RegExp(pattern, 'i');"
+                }]
+            }, {
+                column: 33,
+                endColumn: 40,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{
+                    messageId: "suggestUnicodeFlag",
+                    output: "const pattern = /[👍]/g; RegExp(pattern, 'iu');"
+                }]
+            }]
+        },
+
+        // report only on regex literal if no flags are supplied
+        {
+            code: "RegExp(/[👍]/)",
+            errors: [{
+                column: 10,
+                endColumn: 12,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{ messageId: "suggestUnicodeFlag", output: "RegExp(/[👍]/u)" }]
+            }]
+        },
+
+        // report only on RegExp call if a regex literal and flags are supplied
+        {
+            code: "RegExp(/[👍]/, 'i');",
+            errors: [{
+                column: 10,
+                endColumn: 12,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{ messageId: "suggestUnicodeFlag", output: "RegExp(/[👍]/, 'iu');" }]
+            }]
+        },
+
+        // ignore RegExp if not built-in
+        {
+            code: "RegExp(/[👍]/, 'g');",
+            languageOptions: { globals: { RegExp: "off" } },
+            errors: [{
+                column: 10,
+                endColumn: 12,
+                messageId: "surrogatePairWithoutUFlag",
+                suggestions: [{ messageId: "suggestUnicodeFlag", output: "RegExp(/[👍]/u, 'g');" }]
             }]
         },