From f0207e68505e29419adb5d4a52279bb95cf98835 Mon Sep 17 00:00:00 2001
From: fisker Cheung <lionkay@gmail.com>
Date: Fri, 10 Apr 2020 21:20:40 +0800
Subject: [PATCH] Enable `unicorn/better-regex` (#7991)

* Enable `unicorn/better-regex`

* Spellcheck ignore regex
---
 .editorconfig                                | 1 +
 .eslintrc.yml                                | 1 +
 cspell.json                                  | 3 ++-
 scripts/draft-blog-post.js                   | 4 ++--
 scripts/lint-changelog.js                    | 4 ++--
 scripts/release/steps/update-version.js      | 2 +-
 src/common/util.js                           | 8 ++++----
 src/document/doc-printer.js                  | 4 ++--
 src/language-css/clean.js                    | 6 +++---
 src/language-css/parser-postcss.js           | 4 ++--
 src/language-css/printer-postcss.js          | 8 ++++----
 src/language-css/utils.js                    | 4 ++--
 src/language-graphql/pragma.js               | 2 +-
 src/language-handlebars/printer-glimmer.js   | 4 ++--
 src/language-html/conditional-comment.js     | 6 +++---
 src/language-html/constants.evaluate.js      | 2 +-
 src/language-html/parser-html.js             | 4 ++--
 src/language-html/preprocess.js              | 4 ++--
 src/language-html/printer-html.js            | 4 ++--
 src/language-html/syntax-vue.js              | 6 +++---
 src/language-js/comments.js                  | 2 +-
 src/language-js/embed.js                     | 8 ++++----
 src/language-js/printer-estree.js            | 4 ++--
 src/language-js/utils.js                     | 2 +-
 src/language-markdown/embed.js               | 2 +-
 src/language-markdown/parser-markdown.js     | 2 +-
 src/language-markdown/printer-markdown.js    | 8 ++++----
 src/language-markdown/utils.js               | 2 +-
 src/language-yaml/pragma.js                  | 2 +-
 src/language-yaml/utils.js                   | 2 +-
 tests_integration/__tests__/patterns-dirs.js | 2 +-
 31 files changed, 60 insertions(+), 57 deletions(-)

diff --git a/.editorconfig b/.editorconfig
index 49a6d74cdd74..1cbc8fe300ad 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -10,6 +10,7 @@ insert_final_newline = true
 
 [cspell.json]
 indent_size = 4
+insert_final_newline = false
 
 [website/blog/*.md]
 trim_trailing_whitespace = false
diff --git a/.eslintrc.yml b/.eslintrc.yml
index 28d4f88f0a9a..8b89ff848440 100644
--- a/.eslintrc.yml
+++ b/.eslintrc.yml
@@ -56,6 +56,7 @@ rules:
     - error
     - never
     - exceptRange: true
+  unicorn/better-regex: error
   unicorn/new-for-builtins: error
   unicorn/prefer-includes: error
   unicorn/prefer-set-has: error
diff --git a/cspell.json b/cspell.json
index b223deba330a..399366bf9800 100644
--- a/cspell.json
+++ b/cspell.json
@@ -431,7 +431,8 @@
         "\\[@\\w+?\\]",
         "\\[`\\w+`\\]",
         "ve{2,}r{2,}y",
-        "ve+r+y+long\\w*"
+        "ve+r+y+long\\w*",
+        "\\/.*?\\/"
     ],
     "ignorePaths": [
         "**/node_modules/**",
diff --git a/scripts/draft-blog-post.js b/scripts/draft-blog-post.js
index bce3c86d9d01..28adf7e20e7d 100644
--- a/scripts/draft-blog-post.js
+++ b/scripts/draft-blog-post.js
@@ -67,9 +67,9 @@ for (const dir of dirs) {
         highlight: title.includes("[HIGHLIGHT]"),
         content: [
           title
-            .replace(/\[(BREAKING|HIGHLIGHT)\]/g, "")
+            .replace(/\[(BREAKING|HIGHLIGHT)]/g, "")
             .replace(/\s+/g, " ")
-            .replace(/^#### [a-z]/, (s) => s.toUpperCase()),
+            .replace(/^#{4} [a-z]/, (s) => s.toUpperCase()),
           ...rest,
         ].join("\n"),
       };
diff --git a/scripts/lint-changelog.js b/scripts/lint-changelog.js
index 26ff1c20a0b8..c69f92e2fada 100644
--- a/scripts/lint-changelog.js
+++ b/scripts/lint-changelog.js
@@ -52,14 +52,14 @@ for (const file of [
   }
 }
 
-const authorRegex = /by \[@(.*?)\]\(https:\/\/github\.com\/\1\)/;
+const authorRegex = /by \[@(.*?)]\(https:\/\/github\.com\/\1\)/;
 const titleRegex = /^#{4} (.*?)\(\[#\d{4,}]/;
 
 const template = fs.readFileSync(
   path.join(CHANGELOG_ROOT, TEMPLATE_FILE),
   "utf8"
 );
-const [templateComment] = template.match(/<!--[\s\S]*?-->/);
+const [templateComment] = template.match(/<!--[\S\s]*?-->/);
 const [templateAuthorLink] = template.match(authorRegex);
 
 for (const category of CHANGELOG_CATEGORIES) {
diff --git a/scripts/release/steps/update-version.js b/scripts/release/steps/update-version.js
index 6f01681685de..08182076560c 100644
--- a/scripts/release/steps/update-version.js
+++ b/scripts/release/steps/update-version.js
@@ -21,7 +21,7 @@ async function bump({ version }) {
 
   // Update unpkg link in docs
   processFile("docs/browser.md", (content) =>
-    content.replace(/(\/\/unpkg\.com\/prettier@)(?:.*?)\//g, `$1${version}/`)
+    content.replace(/(\/\/unpkg\.com\/prettier@).*?\//g, `$1${version}/`)
   );
 
   await execa("yarn", ["update-stable-docs"], {
diff --git a/src/common/util.js b/src/common/util.js
index 51ab3a1dce40..0de284663e21 100644
--- a/src/common/util.js
+++ b/src/common/util.js
@@ -73,7 +73,7 @@ const skipToLineEnd = skip(",; \t");
 /**
  * @type {(text: string, index: number | false, opts?: SkipOptions) => number | false}
  */
-const skipEverythingButNewLine = skip(/[^\r\n]/);
+const skipEverythingButNewLine = skip(/[^\n\r]/);
 
 /**
  * @param {string} text
@@ -520,7 +520,7 @@ function getIndentSize(value, tabWidth) {
 
   return getAlignmentSize(
     // All the leading whitespaces
-    value.slice(lastNewlineIndex + 1).match(/^[ \t]*/)[0],
+    value.slice(lastNewlineIndex + 1).match(/^[\t ]*/)[0],
     tabWidth
   );
 }
@@ -624,7 +624,7 @@ function makeString(rawContent, enclosingQuote, unescapeUnnecessaryEscapes) {
   const otherQuote = enclosingQuote === '"' ? "'" : '"';
 
   // Matches _any_ escape and unescaped quotes (both single and double).
-  const regex = /\\([\s\S])|(['"])/g;
+  const regex = /\\([\S\s])|(["'])/g;
 
   // Escape and unescape single and double quotes as needed to be able to
   // enclose `rawContent` with `enclosingQuote`.
@@ -650,7 +650,7 @@ function makeString(rawContent, enclosingQuote, unescapeUnnecessaryEscapes) {
     // Unescape any unnecessarily escaped character.
     // Adapted from https://github.com/eslint/eslint/blob/de0b4ad7bd820ade41b1f606008bea68683dc11a/lib/rules/no-useless-escape.js#L27
     return unescapeUnnecessaryEscapes &&
-      /^[^\\nrvtbfux\r\n\u2028\u2029"'0-7]$/.test(escaped)
+      /^[^\n\r"'0-7\\bfnrt-vx\u2028\u2029]$/.test(escaped)
       ? escaped
       : "\\" + escaped;
   });
diff --git a/src/document/doc-printer.js b/src/document/doc-printer.js
index 737532fb3af5..4f27b04443a5 100644
--- a/src/document/doc-printer.js
+++ b/src/document/doc-printer.js
@@ -121,13 +121,13 @@ function trim(out) {
   while (
     out.length > 0 &&
     typeof out[out.length - 1] === "string" &&
-    out[out.length - 1].match(/^[ \t]*$/)
+    out[out.length - 1].match(/^[\t ]*$/)
   ) {
     trimCount += out.pop().length;
   }
 
   if (out.length && typeof out[out.length - 1] === "string") {
-    const trimmed = out[out.length - 1].replace(/[ \t]*$/, "");
+    const trimmed = out[out.length - 1].replace(/[\t ]*$/, "");
     trimCount += out[out.length - 1].length - trimmed.length;
     out[out.length - 1] = trimmed;
   }
diff --git a/src/language-css/clean.js b/src/language-css/clean.js
index 0bc1016c4116..452834d48c2d 100644
--- a/src/language-css/clean.js
+++ b/src/language-css/clean.js
@@ -113,7 +113,7 @@ function clean(ast, newObj, parent) {
     }
 
     if (newObj.value) {
-      newObj.value = newObj.value.trim().replace(/^['"]|['"]$/g, "");
+      newObj.value = newObj.value.trim().replace(/^["']|["']$/g, "");
       delete newObj.quoted;
     }
   }
@@ -129,7 +129,7 @@ function clean(ast, newObj, parent) {
     newObj.value
   ) {
     newObj.value = newObj.value.replace(
-      /([\d.eE+-]+)([a-zA-Z]*)/g,
+      /([\d+.Ee-]+)([A-Za-z]*)/g,
       (match, numStr, unit) => {
         const num = Number(numStr);
         return isNaN(num) ? match : num + unit.toLowerCase();
@@ -157,7 +157,7 @@ function clean(ast, newObj, parent) {
 }
 
 function cleanCSSStrings(value) {
-  return value.replace(/'/g, '"').replace(/\\([^a-fA-F\d])/g, "$1");
+  return value.replace(/'/g, '"').replace(/\\([^\dA-Fa-f])/g, "$1");
 }
 
 module.exports = clean;
diff --git a/src/language-css/parser-postcss.js b/src/language-css/parser-postcss.js
index cd3fb3c65bf4..e3603a60d925 100644
--- a/src/language-css/parser-postcss.js
+++ b/src/language-css/parser-postcss.js
@@ -464,7 +464,7 @@ function parseNestedCSS(node, options) {
       }
 
       if (name === "at-root") {
-        if (/^\(\s*(without|with)\s*:[\s\S]+\)$/.test(params)) {
+        if (/^\(\s*(without|with)\s*:[\S\s]+\)$/.test(params)) {
           node.params = parseValue(params);
         } else {
           node.selector = parseSelector(params);
@@ -500,7 +500,7 @@ function parseNestedCSS(node, options) {
         ].includes(name)
       ) {
         // Remove unnecessary spaces in SCSS variable arguments
-        params = params.replace(/(\$\S+?)\s+?\.\.\./, "$1...");
+        params = params.replace(/(\$\S+?)\s+?\.{3}/, "$1...");
         // Remove unnecessary spaces before SCSS control, mixin and function directives
         params = params.replace(/^(?!if)(\S+)\s+\(/, "$1(");
 
diff --git a/src/language-css/printer-postcss.js b/src/language-css/printer-postcss.js
index ed7cc9627f02..1fe079f77e36 100644
--- a/src/language-css/printer-postcss.js
+++ b/src/language-css/printer-postcss.js
@@ -974,10 +974,10 @@ function printNodeSequence(path, options, print) {
   return concat(parts);
 }
 
-const STRING_REGEX = /(['"])(?:(?!\1)[^\\]|\\[\s\S])*\1/g;
-const NUMBER_REGEX = /(?:\d*\.\d+|\d+\.?)(?:[eE][+-]?\d+)?/g;
-const STANDARD_UNIT_REGEX = /[a-zA-Z]+/g;
-const WORD_PART_REGEX = /[$@]?[a-zA-Z_\u0080-\uFFFF][\w\-\u0080-\uFFFF]*/g;
+const STRING_REGEX = /(["'])(?:(?!\1)[^\\]|\\[\S\s])*\1/g;
+const NUMBER_REGEX = /(?:\d*\.\d+|\d+\.?)(?:[Ee][+-]?\d+)?/g;
+const STANDARD_UNIT_REGEX = /[A-Za-z]+/g;
+const WORD_PART_REGEX = /[$@]?[A-Z_a-z\u0080-\uFFFF][\w\u0080-\uFFFF-]*/g;
 const ADJUST_NUMBERS_REGEX = new RegExp(
   STRING_REGEX.source +
     "|" +
diff --git a/src/language-css/utils.js b/src/language-css/utils.js
index 1328dd256356..f0bd1cc389ec 100644
--- a/src/language-css/utils.js
+++ b/src/language-css/utils.js
@@ -60,7 +60,7 @@ function getPropOfDeclNode(path) {
 
 function isSCSS(parser, text) {
   const hasExplicitParserChoice = parser === "less" || parser === "scss";
-  const IS_POSSIBLY_SCSS = /(\w\s*:\s*[^}:]+|#){|@import[^\n]+(?:url|,)/;
+  const IS_POSSIBLY_SCSS = /(\w\s*:\s*[^:}]+|#){|@import[^\n]+(?:url|,)/;
   return hasExplicitParserChoice
     ? parser === "scss"
     : IS_POSSIBLY_SCSS.test(text);
@@ -385,7 +385,7 @@ function isLessParser(options) {
 }
 
 function lastLineHasInlineComment(text) {
-  return /\/\//.test(text.split(/[\r\n]/).pop());
+  return /\/\//.test(text.split(/[\n\r]/).pop());
 }
 
 module.exports = {
diff --git a/src/language-graphql/pragma.js b/src/language-graphql/pragma.js
index d41219dc7a0a..af174a325f9e 100644
--- a/src/language-graphql/pragma.js
+++ b/src/language-graphql/pragma.js
@@ -1,7 +1,7 @@
 "use strict";
 
 function hasPragma(text) {
-  return /^\s*#[^\n\S]*@(format|prettier)\s*(\n|$)/.test(text);
+  return /^\s*#[^\S\n]*@(format|prettier)\s*(\n|$)/.test(text);
 }
 
 function insertPragma(text) {
diff --git a/src/language-handlebars/printer-glimmer.js b/src/language-handlebars/printer-glimmer.js
index 6327e43d7007..eca75b26fd53 100644
--- a/src/language-handlebars/printer-glimmer.js
+++ b/src/language-handlebars/printer-glimmer.js
@@ -493,14 +493,14 @@ function countNewLines(string) {
 function countLeadingNewLines(string) {
   /* istanbul ignore next */
   string = typeof string === "string" ? string : "";
-  const newLines = (string.match(/^([^\S\r\n]*[\r\n])+/g) || [])[0] || "";
+  const newLines = (string.match(/^([^\S\n\r]*[\n\r])+/g) || [])[0] || "";
   return countNewLines(newLines);
 }
 
 function countTrailingNewLines(string) {
   /* istanbul ignore next */
   string = typeof string === "string" ? string : "";
-  const newLines = (string.match(/([\r\n][^\S\r\n]*)+$/g) || [])[0] || "";
+  const newLines = (string.match(/([\n\r][^\S\n\r]*)+$/g) || [])[0] || "";
   return countNewLines(newLines);
 }
 
diff --git a/src/language-html/conditional-comment.js b/src/language-html/conditional-comment.js
index 55199c87b977..267b86eac306 100644
--- a/src/language-html/conditional-comment.js
+++ b/src/language-html/conditional-comment.js
@@ -3,11 +3,11 @@
 // https://css-tricks.com/how-to-create-an-ie-only-stylesheet
 
 // <!--[if ... ]> ... <![endif]-->
-const IE_CONDITIONAL_START_END_COMMENT_REGEX = /^(\[if([^\]]*?)\]>)([\s\S]*?)<!\s*\[endif\]$/;
+const IE_CONDITIONAL_START_END_COMMENT_REGEX = /^(\[if([^\]]*?)]>)([\S\s]*?)<!\s*\[endif]$/;
 // <!--[if ... ]><!-->
-const IE_CONDITIONAL_START_COMMENT_REGEX = /^\[if([^\]]*?)\]><!$/;
+const IE_CONDITIONAL_START_COMMENT_REGEX = /^\[if([^\]]*?)]><!$/;
 // <!--<![endif]-->
-const IE_CONDITIONAL_END_COMMENT_REGEX = /^<!\s*\[endif\]$/;
+const IE_CONDITIONAL_END_COMMENT_REGEX = /^<!\s*\[endif]$/;
 
 const REGEX_PARSE_TUPLES = [
   [IE_CONDITIONAL_START_END_COMMENT_REGEX, parseIeConditionalStartEndComment],
diff --git a/src/language-html/constants.evaluate.js b/src/language-html/constants.evaluate.js
index fd52e4f08a67..62eaafcb6de1 100644
--- a/src/language-html/constants.evaluate.js
+++ b/src/language-html/constants.evaluate.js
@@ -13,7 +13,7 @@ const getCssStyleTags = (property) =>
           htmlStyle.selectorText
             .split(",")
             .map((selector) => selector.trim())
-            .filter((selector) => /^[a-zA-Z0-9]+$/.test(selector))
+            .filter((selector) => /^[\dA-Za-z]+$/.test(selector))
             .map((tagName) => [tagName, htmlStyle.style[property]])
         )
     )
diff --git a/src/language-html/parser-html.js b/src/language-html/parser-html.js
index ad9207cf385d..ce88a5010118 100644
--- a/src/language-html/parser-html.js
+++ b/src/language-html/parser-html.js
@@ -93,7 +93,7 @@ function ngHtmlParser(
           attr.value = null;
         } else {
           attr.value = attr.valueSpan.toString();
-          if (/['"]/.test(attr.value[0])) {
+          if (/["']/.test(attr.value[0])) {
             attr.value = attr.value.slice(1, -1);
           }
         }
@@ -204,7 +204,7 @@ function _parse(text, options, parserOptions, shouldParseFrontMatter = true) {
 
   const parseSubHtml = (subContent, startSpan) => {
     const { offset } = startSpan;
-    const fakeContent = text.slice(0, offset).replace(/[^\r\n]/g, " ");
+    const fakeContent = text.slice(0, offset).replace(/[^\n\r]/g, " ");
     const realContent = subContent;
     const subAst = _parse(
       fakeContent + realContent,
diff --git a/src/language-html/preprocess.js b/src/language-html/preprocess.js
index 537ebd751765..956b82d43f9e 100644
--- a/src/language-html/preprocess.js
+++ b/src/language-html/preprocess.js
@@ -232,7 +232,7 @@ function extractInterpolation(ast, options) {
     return ast;
   }
 
-  const interpolationRegex = /\{\{([\s\S]+?)\}\}/g;
+  const interpolationRegex = /{{([\S\s]+?)}}/g;
   return ast.map((node) => {
     if (!canHaveInterpolation(node)) {
       return node;
@@ -337,7 +337,7 @@ function extractWhitespaces(ast /*, options*/) {
           const localChildren = [];
 
           const [, leadingSpaces, text, trailingSpaces] = child.value.match(
-            /^(\s*)([\s\S]*?)(\s*)$/
+            /^(\s*)([\S\s]*?)(\s*)$/
           );
 
           if (leadingSpaces) {
diff --git a/src/language-html/printer-html.js b/src/language-html/printer-html.js
index 721e07e7a0a8..8baaaff21d40 100644
--- a/src/language-html/printer-html.js
+++ b/src/language-html/printer-html.js
@@ -120,7 +120,7 @@ function embed(path, print, textToDoc, options) {
 
       // lwc: html`<my-element data-for={value}></my-element>`
       if (options.parser === "lwc") {
-        const interpolationRegex = /^\{[\s\S]*\}$/;
+        const interpolationRegex = /^{[\S\s]*}$/;
         if (
           interpolationRegex.test(
             options.originalText.slice(
@@ -1100,7 +1100,7 @@ function printEmbeddedAttributeValue(node, originalTextToDoc, options) {
       );
     }
 
-    const interpolationRegex = /\{\{([\s\S]+?)\}\}/g;
+    const interpolationRegex = /{{([\S\s]+?)}}/g;
     const value = getValue();
     if (interpolationRegex.test(value)) {
       const parts = [];
diff --git a/src/language-html/syntax-vue.js b/src/language-html/syntax-vue.js
index 4d5e44e2eaf0..f028eb7e7d71 100644
--- a/src/language-html/syntax-vue.js
+++ b/src/language-html/syntax-vue.js
@@ -29,7 +29,7 @@ function printVueFor(value, textToDoc) {
 // modified from https://github.com/vuejs/vue/blob/v2.5.17/src/compiler/parser/index.js#L370-L387
 function parseVueFor(value) {
   const forAliasRE = /([^]*?)\s+(in|of)\s+([^]*)/;
-  const forIteratorRE = /,([^,}\]]*)(?:,([^,}\]]*))?$/;
+  const forIteratorRE = /,([^,\]}]*)(?:,([^,\]}]*))?$/;
   const stripParensRE = /^\(|\)$/g;
 
   const inMatch = value.match(forAliasRE);
@@ -69,9 +69,9 @@ function printVueSlotScope(value, textToDoc) {
 function isVueEventBindingExpression(eventBindingValue) {
   // https://github.com/vuejs/vue/blob/v2.5.17/src/compiler/codegen/events.js#L3-L4
   // arrow function or anonymous function
-  const fnExpRE = /^([\w$_]+|\([^)]*?\))\s*=>|^function\s*\(/;
+  const fnExpRE = /^([\w$]+|\([^)]*?\))\s*=>|^function\s*\(/;
   // simple member expression chain (a, a.b, a['b'], a["b"], a[0], a[b])
-  const simplePathRE = /^[A-Za-z_$][\w$]*(?:\.[A-Za-z_$][\w$]*|\['[^']*?']|\["[^"]*?"]|\[\d+]|\[[A-Za-z_$][\w$]*])*$/;
+  const simplePathRE = /^[$A-Z_a-z][\w$]*(?:\.[$A-Z_a-z][\w$]*|\['[^']*?']|\["[^"]*?"]|\[\d+]|\[[$A-Z_a-z][\w$]*])*$/;
 
   // https://github.com/vuejs/vue/blob/v2.5.17/src/compiler/helpers.js#L104
   const value = eventBindingValue.trim();
diff --git a/src/language-js/comments.js b/src/language-js/comments.js
index 50aa34987355..0044d54b89bf 100644
--- a/src/language-js/comments.js
+++ b/src/language-js/comments.js
@@ -951,7 +951,7 @@ function getGapRegex(enclosingNode) {
   ) {
     // Support degenerate single-element unions and intersections.
     // E.g.: `type A = /* 1 */ & B`
-    return /^[\s(&|]*$/;
+    return /^[\s&(|]*$/;
   }
 }
 
diff --git a/src/language-js/embed.js b/src/language-js/embed.js
index 679c9d6b37f5..55fde9021264 100644
--- a/src/language-js/embed.js
+++ b/src/language-js/embed.js
@@ -94,11 +94,11 @@ function embed(path, print, textToDoc, options) {
             lines[numLines - 2].trim() === "";
 
           const commentsAndWhitespaceOnly = lines.every((line) =>
-            /^\s*(?:#[^\r\n]*)?$/.test(line)
+            /^\s*(?:#[^\n\r]*)?$/.test(line)
           );
 
           // Bail out if an interpolation occurs within a comment.
-          if (!isLast && /#[^\r\n]*$/.test(lines[numLines - 1])) {
+          if (!isLast && /#[^\n\r]*$/.test(lines[numLines - 1])) {
             return null;
           }
 
@@ -204,7 +204,7 @@ function getIndentation(str) {
 }
 
 function uncook(cookedValue) {
-  return cookedValue.replace(/([\\`]|\$\{)/g, "\\$1");
+  return cookedValue.replace(/([\\`]|\${)/g, "\\$1");
 }
 
 function escapeTemplateCharacters(doc, raw) {
@@ -292,7 +292,7 @@ function replacePlaceholders(quasisDoc, expressionDocs) {
       const placeholder = parts[atPlaceholderIndex];
       const rest = parts.slice(atPlaceholderIndex + 1);
       const placeholderMatch = placeholder.match(
-        /@prettier-placeholder-(.+)-id([\s\S]*)/
+        /@prettier-placeholder-(.+)-id([\S\s]*)/
       );
       const placeholderID = placeholderMatch[1];
       // When the expression has a suffix appended, like:
diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 750a0692444d..5d4298d585bd 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -3641,7 +3641,7 @@ function printPathNoParens(path, options, print, args) {
         )
       );
     case "NGMicrosyntaxKey":
-      return /^[a-z_$][a-z0-9_$]*(-[a-z_$][a-z0-9_$])*$/i.test(n.name)
+      return /^[$_a-z][\w$]*(-[$_a-z][\w$])*$/i.test(n.name)
         ? n.name
         : JSON.stringify(n.name);
     case "NGMicrosyntaxExpression":
@@ -5114,7 +5114,7 @@ function printMemberChain(path, options, print) {
   // letter or just a sequence of _$. The rationale is that they are
   // likely to be factories.
   function isFactory(name) {
-    return /^[A-Z]|^[_$]+$/.test(name);
+    return /^[A-Z]|^[$_]+$/.test(name);
   }
 
   // In case the Identifier is shorter than tab width, we can keep the
diff --git a/src/language-js/utils.js b/src/language-js/utils.js
index 78cd6277df35..9aec30eeec6d 100644
--- a/src/language-js/utils.js
+++ b/src/language-js/utils.js
@@ -731,7 +731,7 @@ function isJestEachTemplateLiteral(node, parentNode) {
    *
    * Ref: https://github.com/facebook/jest/pull/6102
    */
-  const jestEachTriggerRegex = /^[xf]?(describe|it|test)$/;
+  const jestEachTriggerRegex = /^[fx]?(describe|it|test)$/;
   return (
     parentNode.type === "TaggedTemplateExpression" &&
     parentNode.quasi === node &&
diff --git a/src/language-markdown/embed.js b/src/language-markdown/embed.js
index 2919ffce4329..fe5e2bcf2bef 100644
--- a/src/language-markdown/embed.js
+++ b/src/language-markdown/embed.js
@@ -13,7 +13,7 @@ function embed(path, print, textToDoc, options) {
 
   if (node.type === "code" && node.lang !== null) {
     // only look for the first string so as to support [markdown-preview-enhanced](https://shd101wyy.github.io/markdown-preview-enhanced/#/code-chunk)
-    const langMatch = node.lang.match(/^[A-Za-z0-9_-]+/);
+    const langMatch = node.lang.match(/^[\w-]+/);
     const lang = langMatch ? langMatch[0] : "";
     const parser = getParserName(lang);
     if (parser) {
diff --git a/src/language-markdown/parser-markdown.js b/src/language-markdown/parser-markdown.js
index a9e4f61836ca..67a352a3628a 100644
--- a/src/language-markdown/parser-markdown.js
+++ b/src/language-markdown/parser-markdown.js
@@ -80,7 +80,7 @@ function liquid() {
   proto.inlineTokenizers.liquid = tokenizer;
 
   function tokenizer(eat, value) {
-    const match = value.match(/^({%[\s\S]*?%}|{{[\s\S]*?}})/);
+    const match = value.match(/^({%[\S\s]*?%}|{{[\S\s]*?}})/);
 
     if (match) {
       return eat(match[0])({
diff --git a/src/language-markdown/printer-markdown.js b/src/language-markdown/printer-markdown.js
index c2cd2f40c93a..fa4c566b52fd 100644
--- a/src/language-markdown/printer-markdown.js
+++ b/src/language-markdown/printer-markdown.js
@@ -81,7 +81,7 @@ function genericPrint(path, options, print) {
       return printChildren(path, options, print);
     case "word":
       return node.value
-        .replace(/[*$]/g, "\\$&") // escape all `*` and `$` (math)
+        .replace(/[$*]/g, "\\$&") // escape all `*` and `$` (math)
         .replace(
           new RegExp(
             [
@@ -103,7 +103,7 @@ function genericPrint(path, options, print) {
 
       const proseWrap =
         // leading char that may cause different syntax
-        nextNode && /^>|^([-+*]|#{1,6}|[0-9]+[.)])$/.test(nextNode.value)
+        nextNode && /^>|^([*+-]|#{1,6}|\d+[).])$/.test(nextNode.value)
           ? "never"
           : options.proseWrap;
 
@@ -236,7 +236,7 @@ function genericPrint(path, options, print) {
         privateUtil.getLast(parentNode.children) === node
           ? node.value.trimEnd()
           : node.value;
-      const isHtmlComment = /^<!--[\s\S]*-->$/.test(value);
+      const isHtmlComment = /^<!--[\S\s]*-->$/.test(value);
       return concat(
         replaceEndOfLineWith(
           value,
@@ -951,7 +951,7 @@ function clean(ast, newObj, parent) {
   }
 
   if (ast.type === "inlineCode") {
-    newObj.value = ast.value.replace(/[ \t\n]+/g, " ");
+    newObj.value = ast.value.replace(/[\t\n ]+/g, " ");
   }
 
   // for insert pragma
diff --git a/src/language-markdown/utils.js b/src/language-markdown/utils.js
index 05abf00fc1aa..a7a6dde8dd50 100644
--- a/src/language-markdown/utils.js
+++ b/src/language-markdown/utils.js
@@ -52,7 +52,7 @@ function splitText(text, options) {
     ? text
     : text.replace(new RegExp(`(${cjkPattern})\n(${cjkPattern})`, "g"), "$1$2")
   )
-    .split(/([ \t\n]+)/)
+    .split(/([\t\n ]+)/)
     .forEach((token, index, tokens) => {
       // whitespace
       if (index % 2 === 1) {
diff --git a/src/language-yaml/pragma.js b/src/language-yaml/pragma.js
index 56225a0d33e4..f65ca0dd2117 100644
--- a/src/language-yaml/pragma.js
+++ b/src/language-yaml/pragma.js
@@ -5,7 +5,7 @@ function isPragma(text) {
 }
 
 function hasPragma(text) {
-  return /^\s*#[^\n\S]*@(prettier|format)\s*?(\n|$)/.test(text);
+  return /^\s*#[^\S\n]*@(prettier|format)\s*?(\n|$)/.test(text);
 }
 
 function insertPragma(text) {
diff --git a/src/language-yaml/utils.js b/src/language-yaml/utils.js
index 0ff8f6ed79fb..c4bb86426fbc 100644
--- a/src/language-yaml/utils.js
+++ b/src/language-yaml/utils.js
@@ -246,7 +246,7 @@ function getBlockValueLineContents(
       : options.originalText
           .slice(node.position.start.offset, node.position.end.offset)
           // exclude open line `>` or `|`
-          .match(/^[^\n]*?\n([\s\S]*)$/)[1];
+          .match(/^[^\n]*?\n([\S\s]*)$/)[1];
 
   const leadingSpaceCount =
     node.indent === null
diff --git a/tests_integration/__tests__/patterns-dirs.js b/tests_integration/__tests__/patterns-dirs.js
index 0f7b25b23e5b..0818ab93bf66 100644
--- a/tests_integration/__tests__/patterns-dirs.js
+++ b/tests_integration/__tests__/patterns-dirs.js
@@ -95,7 +95,7 @@ function testPatterns(namePrefix, cliArgs, expected = {}) {
     (namePrefix ? namePrefix + ": " : "") +
     "prettier " +
     cliArgs
-      .map((arg) => (/^[\w.=/-]+$/.test(arg) ? arg : `'${arg}'`))
+      .map((arg) => (/^[\w./=-]+$/.test(arg) ? arg : `'${arg}'`))
       .join(" ");
 
   describe(testName, () => {