feat(new tool): Regex Tester (and Cheatsheet) (#1030)

* feat(new tool): Regex Tester

Fix https://github.com/CorentinTh/it-tools/issues/1007, https://github.com/CorentinTh/it-tools/issues/991, https://github.com/CorentinTh/it-tools/issues/936, https://github.com/CorentinTh/it-tools/issues/761, https://github.com/CorentinTh/it-tools/issues/649
https://github.com/CorentinTh/it-tools/issues/644, https://github.com/CorentinTh/it-tools/issues/554
https://github.com/CorentinTh/it-tools/issues/308

* fix: refactor to service + add regex diagram + ui enhancements

* fix: update queryParams

* fix: deps

* fix: svg style bug in @regexper/render

@regexper/render use a stylesheet in svg that cause bugs in whole site. So add regexper in a shadow root

* feat(new tool): added Regex Cheatsheet

* Update src/tools/regex-memo/index.ts

* Update src/tools/regex-tester/index.ts

---------

Co-authored-by: Corentin THOMASSET <corentin.thomasset74@gmail.com>

src/composable/queryParams.ts

@@ -1,7 +1,8 @@
 import { useRouteQuery } from '@vueuse/router';
 import { computed } from 'vue';
+import { useStorage } from '@vueuse/core';
 
-export { useQueryParam };
+export { useQueryParam, useQueryParamOrStorage };
 
 const transformers = {
   number: {
@@ -16,6 +17,12 @@ const transformers = {
     fromQuery: (value: string) => value.toLowerCase() === 'true',
     toQuery: (value: boolean) => (value ? 'true' : 'false'),
   },
+  object: {
+    fromQuery: (value: string) => {
+      return JSON.parse(value);
+    },
+    toQuery: (value: object) => JSON.stringify(value),
+  },
 };
 
 function useQueryParam<T>({ name, defaultValue }: { name: string; defaultValue: T }) {
@@ -33,3 +40,27 @@ function useQueryParam<T>({ name, defaultValue }: { name: string; defaultValue:
     },
   });
 }
+
+function useQueryParamOrStorage<T>({ name, storageName, defaultValue }: { name: string; storageName: string; defaultValue: T }) {
+  const type = typeof defaultValue;
+  const transformer = transformers[type as keyof typeof transformers] ?? transformers.string;
+
+  const storageRef = useStorage(storageName, defaultValue);
+  const proxyDefaultValue = transformer.toQuery(defaultValue as never);
+  const proxy = useRouteQuery(name, proxyDefaultValue);
+
+  const r = ref(defaultValue);
+
+  watch(r,
+    (value) => {
+      proxy.value = transformer.toQuery(value as never);
+      storageRef.value = value as never;
+    },
+    { deep: true });
+
+  r.value = (proxy.value && proxy.value !== proxyDefaultValue
+    ? transformer.fromQuery(proxy.value) as unknown as T
+    : storageRef.value as T) as never;
+
+  return r;
+}

src/composable/validation.ts

@@ -3,9 +3,11 @@ import _ from 'lodash';
 import { type Ref, reactive, watch } from 'vue';
 
 type ValidatorReturnType = unknown;
+type GetErrorMessageReturnType = string;
 
 export interface UseValidationRule<T> {
   validator: (value: T) => ValidatorReturnType
+  getErrorMessage?: (value: T) => GetErrorMessageReturnType
   message: string
 }
 
@@ -24,6 +26,15 @@ export function isFalsyOrHasThrown(cb: () => ValidatorReturnType): boolean {
   }
 }
 
+export function getErrorMessageOrThrown(cb: () => GetErrorMessageReturnType): string {
+  try {
+    return cb() || '';
+  }
+  catch (e: any) {
+    return e.toString();
+  }
+}
+
 export interface ValidationAttrs {
   feedback: string
   validationStatus: string | undefined
@@ -61,7 +72,13 @@ export function useValidation<T>({
 
       for (const rule of get(rules)) {
         if (isFalsyOrHasThrown(() => rule.validator(source.value))) {
-          state.message = rule.message;
+          if (rule.getErrorMessage) {
+            const getErrorMessage = rule.getErrorMessage;
+            state.message = rule.message.replace('{0}', getErrorMessageOrThrown(() => getErrorMessage(source.value)));
+          }
+          else {
+            state.message = rule.message;
+          }
           state.status = 'error';
         }
       }

src/main.ts

@@ -3,6 +3,7 @@ import { createPinia } from 'pinia';
 import { createHead } from '@vueuse/head';
 
 import { registerSW } from 'virtual:pwa-register';
+import shadow from 'vue-shadow-dom';
 import { plausible } from './plugins/plausible.plugin';
 
 import 'virtual:uno.css';
@@ -23,5 +24,6 @@ app.use(i18nPlugin);
 app.use(router);
 app.use(naive);
 app.use(plausible);
+app.use(shadow);
 
 app.mount('#app');

src/tools/index.ts

@@ -9,6 +9,8 @@ import { tool as textToUnicode } from './text-to-unicode';
 import { tool as safelinkDecoder } from './safelink-decoder';
 import { tool as xmlToJson } from './xml-to-json';
 import { tool as jsonToXml } from './json-to-xml';
+import { tool as regexTester } from './regex-tester';
+import { tool as regexMemo } from './regex-memo';
 import { tool as markdownToHtml } from './markdown-to-html';
 import { tool as pdfSignatureChecker } from './pdf-signature-checker';
 import { tool as numeronymGenerator } from './numeronym-generator';
@@ -156,6 +158,8 @@ export const toolsByCategory: ToolCategory[] = [
       xmlFormatter,
       yamlViewer,
       emailNormalizer,
+      regexTester,
+      regexMemo,
     ],
   },
   {

src/tools/regex-memo/index.ts

@@ -0,0 +1,12 @@
+import { BrandJavascript } from '@vicons/tabler';
+import { defineTool } from '../tool';
+
+export const tool = defineTool({
+  name: 'Regex cheatsheet',
+  path: '/regex-memo',
+  description: 'Javascript Regex/Regular Expression cheatsheet',
+  keywords: ['regex', 'regular', 'expression', 'javascript', 'memo', 'cheatsheet'],
+  component: () => import('./regex-memo.vue'),
+  icon: BrandJavascript,
+  createdAt: new Date('2024-09-20'),
+});

src/tools/regex-memo/regex-memo.content.md

@@ -0,0 +1,121 @@
+### Normal characters
+
+Expression | Description
+:--|:--
+`.` or `[^\n\r]` | any character *excluding* a newline or carriage return
+`[A-Za-z]` | alphabet
+`[a-z]` | lowercase alphabet
+`[A-Z]` | uppercase alphabet
+`\d` or `[0-9]` | digit
+`\D` or `[^0-9]` | non-digit
+`_` | underscore
+`\w` or `[A-Za-z0-9_]` | alphabet, digit or underscore
+`\W` or `[^A-Za-z0-9_]` | inverse of `\w`
+`\S` | inverse of `\s`
+
+### Whitespace characters
+
+Expression | Description
+:--|:--
+` ` | space
+`\t` | tab
+`\n` | newline
+`\r` | carriage return
+`\s` | space, tab, newline or carriage return
+
+### Character set
+
+Expression | Description
+:--|:--
+`[xyz]` | either `x`, `y` or `z`
+`[^xyz]` | neither `x`, `y` nor `z`
+`[1-3]` | either `1`, `2` or `3`
+`[^1-3]` | neither `1`, `2` nor `3`
+
+- Think of a character set as an `OR` operation on the single characters that are enclosed between the square brackets.
+- Use `^` after the opening `[` to “negate” the character set.
+- Within a character set, `.` means a literal period.
+
+### Characters that require escaping
+
+#### Outside a character set
+
+Expression | Description
+:--|:--
+`\.` | period
+`\^` | caret
+`\$` | dollar sign
+`\|` | pipe
+`\\` | back slash
+`\/` | forward slash
+`\(` | opening bracket
+`\)` | closing bracket
+`\[` | opening square bracket
+`\]` | closing square bracket
+`\{` | opening curly bracket
+`\}` | closing curly bracket
+
+#### Inside a character set
+
+Expression | Description
+:--|:--
+`\\` | back slash
+`\]` | closing square bracket
+
+- A `^` must be escaped only if it occurs immediately after the opening `[` of the character set.
+- A `-` must be escaped only if it occurs between two alphabets or two digits.
+
+### Quantifiers
+
+Expression | Description
+:--|:--
+`{2}` | exactly 2
+`{2,}` | at least 2
+`{2,7}` | at least 2 but no more than 7
+`*` | 0 or more
+`+` | 1 or more
+`?` | exactly 0 or 1
+
+- The quantifier goes *after* the expression to be quantified.
+
+### Boundaries
+
+Expression | Description
+:--|:--
+`^` | start of string
+`$` | end of string
+`\b` | word boundary
+
+- How word boundary matching works:
+    - At the beginning of the string if the first character is `\w`.
+    - Between two adjacent characters within the string, if the first character is `\w` and the second character is `\W`.
+    - At the end of the string if the last character is `\w`.
+
+### Matching
+
+Expression | Description
+:--|:--
+`foo\|bar` | match either `foo` or `bar`
+`foo(?=bar)` | match `foo` if it’s before `bar`
+`foo(?!bar)` | match `foo` if it’s *not* before `bar`
+`(?<=bar)foo` | match `foo` if it’s after `bar`
+`(?<!bar)foo` | match `foo` if it’s *not* after `bar`
+
+### Grouping and capturing
+
+Expression | Description
+:--|:--
+`(foo)` | capturing group; match and capture `foo`
+`(?:foo)` | non-capturing group; match `foo` but *without* capturing `foo`
+`(foo)bar\1` | `\1` is a backreference to the 1st capturing group; match `foobarfoo`
+
+- Capturing groups are only relevant in the following methods:
+    - `string.match(regexp)`
+    - `string.matchAll(regexp)`
+    - `string.replace(regexp, callback)`
+- `\N` is a backreference to the `Nth` capturing group. Capturing groups are numbered starting from 1.
+
+## References and tools
+
+- [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions)
+- [RegExplained](https://leaverou.github.io/regexplained/)

src/tools/regex-memo/regex-memo.vue

@@ -0,0 +1,32 @@
+<script setup lang="ts">
+import { useThemeVars } from 'naive-ui';
+import Memo from './regex-memo.content.md';
+
+const themeVars = useThemeVars();
+</script>
+
+<template>
+  <div>
+    <Memo />
+  </div>
+</template>
+
+<style lang="less" scoped>
+::v-deep(pre) {
+  margin: 0;
+  padding: 15px 22px;
+  background-color: v-bind('themeVars.cardColor');
+  border-radius: 4px;
+  overflow: auto;
+}
+::v-deep(table) {
+  border-collapse: collapse;
+}
+::v-deep(table), ::v-deep(td), ::v-deep(th) {
+  border: 1px solid v-bind('themeVars.textColor1');
+  padding: 5px;
+}
+::v-deep(a) {
+  color: v-bind('themeVars.textColor1');
+}
+</style>

src/tools/regex-tester/index.ts

@@ -0,0 +1,12 @@
+import { Language } from '@vicons/tabler';
+import { defineTool } from '../tool';
+
+export const tool = defineTool({
+  name: 'Regex Tester',
+  path: '/regex-tester',
+  description: 'Regex Tester',
+  keywords: ['regex', 'tester', 'sample', 'expression'],
+  component: () => import('./regex-tester.vue'),
+  icon: Language,
+  createdAt: new Date('2024-09-20'),
+});

src/tools/regex-tester/regex-tester.service.test.ts

@@ -0,0 +1,106 @@
+import { describe, expect, it } from 'vitest';
+import { matchRegex } from './regex-tester.service';
+
+const regexesData = [
+  {
+    regex: '',
+    text: '',
+    flags: '',
+    result: [],
+  },
+  {
+    regex: '.*',
+    text: '',
+    flags: '',
+    result: [],
+  },
+  {
+    regex: '',
+    text: 'aaa',
+    flags: '',
+    result: [],
+  },
+  {
+    regex: 'a',
+    text: 'baaa',
+    flags: '',
+    result: [
+      {
+        captures: [],
+        groups: [],
+        index: 1,
+        value: 'a',
+      },
+    ],
+  },
+  {
+    regex: '(.)(?<g>r)',
+    text: 'azertyr',
+    flags: 'g',
+    result: [
+      {
+        captures: [
+          {
+            end: 3,
+            name: '1',
+            start: 2,
+            value: 'e',
+          },
+          {
+            end: 4,
+            name: '2',
+            start: 3,
+            value: 'r',
+          },
+        ],
+        groups: [
+          {
+            end: 4,
+            name: 'g',
+            start: 3,
+            value: 'r',
+          },
+        ],
+        index: 2,
+        value: 'er',
+      },
+      {
+        captures: [
+          {
+            end: 6,
+            name: '1',
+            start: 5,
+            value: 'y',
+          },
+          {
+            end: 7,
+            name: '2',
+            start: 6,
+            value: 'r',
+          },
+        ],
+        groups: [
+          {
+            end: 7,
+            name: 'g',
+            start: 6,
+            value: 'r',
+          },
+        ],
+        index: 5,
+        value: 'yr',
+      },
+    ],
+  },
+];
+
+describe('regex-tester', () => {
+  for (const reg of regexesData) {
+    const { regex, text, flags, result: expected_result } = reg;
+    it(`Should matchRegex("${regex}","${text}","${flags}") return correct result`, async () => {
+      const result = matchRegex(regex, text, `${flags}d`);
+
+      expect(result).to.deep.equal(expected_result);
+    });
+  }
+});

src/tools/regex-tester/regex-tester.service.ts

@@ -0,0 +1,61 @@
+interface RegExpGroupIndices {
+  [name: string]: [number, number]
+}
+interface RegExpIndices extends Array<[number, number]> {
+  groups: RegExpGroupIndices
+}
+interface RegExpExecArrayWithIndices extends RegExpExecArray {
+  indices: RegExpIndices
+}
+interface GroupCapture {
+  name: string
+  value: string
+  start: number
+  end: number
+};
+
+export function matchRegex(regex: string, text: string, flags: string) {
+  // if (regex === '' || text === '') {
+  //   return [];
+  // }
+
+  let lastIndex = -1;
+  const re = new RegExp(regex, flags);
+  const results = [];
+  let match = re.exec(text) as RegExpExecArrayWithIndices;
+  while (match !== null) {
+    if (re.lastIndex === lastIndex || match[0] === '') {
+      break;
+    }
+    const indices = match.indices;
+    const captures: Array<GroupCapture> = [];
+    Object.entries(match).forEach(([captureName, captureValue]) => {
+      if (captureName !== '0' && captureName.match(/\d+/)) {
+        captures.push({
+          name: captureName,
+          value: captureValue,
+          start: indices[Number(captureName)][0],
+          end: indices[Number(captureName)][1],
+        });
+      }
+    });
+    const groups: Array<GroupCapture> = [];
+    Object.entries(match.groups || {}).forEach(([groupName, groupValue]) => {
+      groups.push({
+        name: groupName,
+        value: groupValue,
+        start: indices.groups[groupName][0],
+        end: indices.groups[groupName][1],
+      });
+    });
+    results.push({
+      index: match.index,
+      value: match[0],
+      captures,
+      groups,
+    });
+    lastIndex = re.lastIndex;
+    match = re.exec(text) as RegExpExecArrayWithIndices;
+  }
+  return results;
+}

src/tools/regex-tester/regex-tester.vue

@@ -0,0 +1,193 @@
+<script setup lang="ts">
+import RandExp from 'randexp';
+import { render } from '@regexper/render';
+import type { ShadowRootExpose } from 'vue-shadow-dom';
+import { matchRegex } from './regex-tester.service';
+import { useValidation } from '@/composable/validation';
+import { useQueryParamOrStorage } from '@/composable/queryParams';
+
+const regex = useQueryParamOrStorage({ name: 'regex', storageName: 'regex-tester:regex', defaultValue: '' });
+const text = ref('');
+const global = ref(true);
+const ignoreCase = ref(false);
+const multiline = ref(false);
+const dotAll = ref(true);
+const unicode = ref(true);
+const unicodeSets = ref(false);
+const visualizerSVG = ref<ShadowRootExpose>();
+
+const regexValidation = useValidation({
+  source: regex,
+  rules: [
+    {
+      message: 'Invalid regex: {0}',
+      validator: value => new RegExp(value),
+      getErrorMessage: (value) => {
+        const _ = new RegExp(value);
+        return '';
+      },
+    },
+  ],
+});
+const results = computed(() => {
+  let flags = 'd';
+  if (global.value) {
+    flags += 'g';
+  }
+  if (ignoreCase.value) {
+    flags += 'i';
+  }
+  if (multiline.value) {
+    flags += 'm';
+  }
+  if (dotAll.value) {
+    flags += 's';
+  }
+  if (unicode.value) {
+    flags += 'u';
+  }
+  else if (unicodeSets.value) {
+    flags += 'v';
+  }
+
+  try {
+    return matchRegex(regex.value, text.value, flags);
+  }
+  catch (_) {
+    return [];
+  }
+});
+
+const sample = computed(() => {
+  try {
+    const randexp = new RandExp(new RegExp(regex.value.replace(/\(\?\<[^\>]*\>/g, '(?:')));
+    return randexp.gen();
+  }
+  catch (_) {
+    return '';
+  }
+});
+
+watchEffect(
+  async () => {
+    const regexValue = regex.value;
+    // shadow root is required:
+    // @regexper/render append a <defs><style> that broke svg transparency of icons in the whole site
+    const visualizer = visualizerSVG.value?.shadow_root;
+    if (visualizer) {
+      while (visualizer.lastChild) {
+        visualizer.removeChild(visualizer.lastChild);
+      }
+      const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      try {
+        await render(regexValue, svg);
+      }
+      catch (_) {
+      }
+      visualizer.appendChild(svg);
+    }
+  },
+);
+</script>
+
+<template>
+  <div max-w-600px>
+    <c-card title="Regex" mb-1>
+      <c-input-text
+        v-model:value="regex"
+        label="Regex to test:"
+        placeholder="Put the regex to test"
+        multiline
+        rows="3"
+        :validation="regexValidation"
+      />
+      <router-link target="_blank" to="/regex-memo" mb-1 mt-1>
+        See Regular Expression Cheatsheet
+      </router-link>
+      <n-space>
+        <n-checkbox v-model:checked="global">
+          <span title="Global search">Global search. (<code>g</code>)</span>
+        </n-checkbox>
+        <n-checkbox v-model:checked="ignoreCase">
+          <span title="Case-insensitive search">Case-insensitive search. (<code>i</code>)</span>
+        </n-checkbox>
+        <n-checkbox v-model:checked="multiline">
+          <span title="Allows ^ and $ to match next to newline characters.">Multiline(<code>m</code>)</span>
+        </n-checkbox>
+        <n-checkbox v-model:checked="dotAll">
+          <span title="Allows . to match newline characters.">Singleline(<code>s</code>)</span>
+        </n-checkbox>
+        <n-checkbox v-model:checked="unicode">
+          <span title="Unicode; treat a pattern as a sequence of Unicode code points.">Unicode(<code>u</code>)</span>
+        </n-checkbox>
+        <n-checkbox v-model:checked="unicodeSets">
+          <span title="An upgrade to the u mode with more Unicode features.">Unicode Sets (<code>v</code>)</span>
+        </n-checkbox>
+      </n-space>
+
+      <n-divider />
+
+      <c-input-text
+        v-model:value="text"
+        label="Text to match:"
+        placeholder="Put the text to match"
+        multiline
+        rows="5"
+      />
+    </c-card>
+
+    <c-card title="Matches" mb-1 mt-3>
+      <n-table v-if="results?.length > 0">
+        <thead>
+          <tr>
+            <th scope="col">
+              Index in text
+            </th>
+            <th scope="col">
+              Value
+            </th>
+            <th scope="col">
+              Captures
+            </th>
+            <th scope="col">
+              Groups
+            </th>
+          </tr>
+        </thead>
+        <tbody>
+          <tr v-for="match of results" :key="match.index">
+            <td>{{ match.index }}</td>
+            <td>{{ match.value }}</td>
+            <td>
+              <ul>
+                <li v-for="capture in match.captures" :key="capture.name">
+                  "{{ capture.name }}" = {{ capture.value }} [{{ capture.start }} - {{ capture.end }}]
+                </li>
+              </ul>
+            </td>
+            <td>
+              <ul>
+                <li v-for="group in match.groups" :key="group.name">
+                  "{{ group.name }}" = {{ group.value }} [{{ group.start }} - {{ group.end }}]
+                </li>
+              </ul>
+            </td>
+          </tr>
+        </tbody>
+      </n-table>
+      <c-alert v-else>
+        No match
+      </c-alert>
+    </c-card>
+
+    <c-card title="Sample matching text" mt-3>
+      <pre style="white-space: pre-wrap; word-break: break-all;">{{ sample }}</pre>
+    </c-card>
+
+    <c-card title="Regex Diagram" style="overflow-x: scroll;" mt-3>
+      <shadow-root ref="visualizerSVG">
+&#xa0;
+      </shadow-root>
+    </c-card>
+  </div>
+</template>