Use official pug-lint to lint pug files (#65)

* WIP: Make sure to pass items to puglint

* Group test cases instead of defining just valid/invalid cases

* Make more complicated tests for pug-lint

* Make sure pug-lint works well with indentation

* Improve integration with Attribute Brackets rule

* Make sure we work properly with one-line statements

* Make sure we describe the rule for others

* Make sure we mention pug-lint in main configuration

README.md

@@ -61,3 +61,7 @@ Then configure the rules you want to use under the rules section.
 * [`react-pug/quotes`](./docs/rules/quotes.md): Manage quotes in Pug
 * [`react-pug/uses-react`](./docs/rules/uses-react.md): Prevent React to be marked as unused
 * [`react-pug/uses-vars`](./docs/rules/uses-vars.md): Prevent variables used in Pug to be marked as unused
+
+Experimental:
+
+* [`react-pug/pug-lint`](./docs/rules/pug-lint.md): Inherit pug-lint to validate pug

docs/rules/pug-lint.md

@@ -0,0 +1,31 @@
+# Inherit pug-lint to validate pug (experimental)
+
+This rule applies pug-lint to pug templates in js.
+
+[See pug-lint project](https://github.com/pugjs/pug-lint)
+
+## Rule Details
+
+The following patterns are considered warnings:
+
+```jsx
+/*eslint react-pug/pug-lint: ["error", { "requireSpaceAfterCodeOperator": true }]*/
+pug`div=greeting`
+```
+
+```jsx
+/*eslint react-pug/pug-lint: ["error", { "disallowTrailingSpaces": true }]*/
+pug`div: img() `
+```
+
+The following patterns are **not** considered warnings:
+
+```jsx
+/*eslint react-pug/pug-lint: ["error", { "requireSpaceAfterCodeOperator": true }]*/
+pug`div= greeting`
+```
+
+```jsx
+/*eslint react-pug/pug-lint: ["error", { "disallowTrailingSpaces": true }]*/
+pug`div: img()`
+```

index.js

@@ -10,6 +10,7 @@ const allRules = {
   'no-broken-template': require('./lib/rules/no-broken-template'),
   'no-interpolation': require('./lib/rules/no-interpolation'),
   'no-undef': require('./lib/rules/no-undef'),
+  'pug-lint': require('./lib/rules/pug-lint'),
   quotes: require('./lib/rules/quotes'),
   'uses-react': require('./lib/rules/uses-react'),
   'uses-vars': require('./lib/rules/uses-vars'),
@@ -29,6 +30,7 @@ module.exports = {
         'react-pug/indent': 2,
         'react-pug/no-broken-template': 2,
         'react-pug/no-undef': 2,
+        'react-pug/pug-lint': 2,
         'react-pug/no-interpolation': 2,
         'react-pug/quotes': 2,
         'react-pug/uses-react': 2,

lib/rules/pug-lint.js

@@ -0,0 +1,118 @@
+/**
+ * @fileoverview Inherit pug-lint to validate pug
+ * @author Eugene Zhlobo
+ */
+
+const Linter = require('pug-lint')
+const common = require('common-prefix')
+
+const { isReactPugReference, buildLocation, docsUrl } = require('../util/eslint')
+const getTemplate = require('../util/getTemplate')
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+const buildMessage = actual => (
+  `Invalid indentation, found "${actual}" spaces`
+)
+
+module.exports = {
+  meta: {
+    docs: {
+      description: 'Inherit pug-lint to validate pug (experimental)',
+      category: 'Stylistic Issues',
+      recommended: false,
+      url: docsUrl('pug-lint'),
+    },
+    schema: [
+      {
+        type: 'object',
+      },
+    ],
+  },
+
+  create: function (context) {
+    return {
+      TaggedTemplateExpression: function (node) {
+        if (isReactPugReference(node)) {
+          const template = getTemplate(node)
+          const lines = template.split('\n')
+
+          const linter = new Linter()
+
+          linter.configure(context.options[0])
+
+          const firstTokenInLine = context
+            .getSourceCode()
+            .getTokensBefore(node, {
+              filter: token => token.loc.end.line === node.loc.start.line,
+            })[0]
+
+          const minimalIndent = firstTokenInLine
+            ? firstTokenInLine.loc.start.column
+            : node.loc.start.column
+
+          const desiredIndent = lines.length > 1
+            ? minimalIndent + 2
+            : 0
+
+          const amountOfUselessSpaces = common(lines.filter(item => item.trim() !== ''))
+            .replace(/^(\s*).*/, '$1')
+            .length
+
+          if (amountOfUselessSpaces > 0 && amountOfUselessSpaces < desiredIndent) {
+            context.report({
+              node,
+              message: buildMessage(amountOfUselessSpaces),
+              loc: buildLocation(
+                [(node.loc.start.line + 1), 0],
+                [(node.loc.start.line + 1), amountOfUselessSpaces],
+              ),
+            })
+
+            return null
+          }
+
+          // We need to pass the template without not valuable spaces in the
+          // beginning of each line
+          const preparedTemplate = lines
+            .map(item => item.slice(desiredIndent))
+            .join('\n')
+
+          const result = linter.checkString(preparedTemplate, 'testfile')
+
+          if (result.length) {
+            result.forEach((error) => {
+              const delta = error.line === 1
+                // When template starts plus backtick
+                ? node.quasi.quasis[0].loc.start.column + 1
+                : desiredIndent - 1
+
+              let columnStart = error.column + delta
+              let columnEnd = error.column + delta
+              let message = error.msg
+
+              if (error.msg === 'Invalid indentation') {
+                columnStart = 0
+                columnEnd = preparedTemplate.split('\n')[error.line - 1].replace(/^(\s*).*/, '$1').length + desiredIndent
+                message = buildMessage(columnEnd)
+              }
+
+              context.report({
+                node,
+                message,
+                loc: buildLocation(
+                  [(node.loc.start.line + error.line) - 1, columnStart],
+                  [(node.loc.start.line + error.line) - 1, columnEnd],
+                ),
+              })
+            })
+          }
+        }
+
+        return null
+      },
+    }
+  },
+}

lib/util/testBuildCases.js

@@ -0,0 +1,19 @@
+const extractCase = type => item => ({
+  options: item.options || [],
+  ...item[type],
+})
+
+const extractCases = type => (items) => {
+  if (items.some(item => item.only)) {
+    return items.filter(item => item.only).map(extractCase(type))
+  }
+
+  return items.map(extractCase(type))
+}
+
+module.exports = function (cases) {
+  return {
+    valid: extractCases('valid')(cases),
+    invalid: extractCases('invalid')(cases),
+  }
+}

package.json

@@ -28,7 +28,9 @@
   "dependencies": {
     "@babel/parser": "^7.3.2",
     "@babel/traverse": "^7.2.3",
+    "common-prefix": "^1.1.0",
     "pug-lexer": "^4.0.0",
+    "pug-lint": "^2.5.0",
     "pug-uses-variables": "^3.0.0"
   },
   "devDependencies": {

tests/each-rule.js

@@ -34,7 +34,7 @@ describe('each rule', () => {
   describe('mentioned in README', () => {
     const listOfRulesInReadme = fs
       .readFileSync(path.resolve(__dirname, '..', 'README.md'), 'utf-8')
-      .match(/## List of supported rules\n+((\*.+\n+)+)/m)[1]
+      .match(/## List of supported rules\n+((\*.+\n+|^[^#]+)+)/m)[1]
       .split('\n')
       .filter(Boolean)
 

tests/lib/rules/eslint.js

@@ -9,6 +9,7 @@
 
 const eslint = require('eslint')
 const buildError = require('../../../lib/util/testBuildError')
+const buildCases = require('../../../lib/util/testBuildCases')
 
 const { RuleTester } = eslint
 
@@ -216,20 +217,4 @@ const cases = [
   },
 ]
 
-const extractCase = type => item => ({
-  options: item.options || [],
-  ...item[type],
-})
-
-const extractCases = type => (items) => {
-  if (items.some(item => item.only)) {
-    return items.filter(item => item.only).map(extractCase(type))
-  }
-
-  return items.map(extractCase(type))
-}
-
-ruleTester.run('rule "eslint"', rule, {
-  valid: extractCases('valid')(cases),
-  invalid: extractCases('invalid')(cases),
-})
+ruleTester.run('rule "eslint"', rule, buildCases(cases))