Add prettier support

lib/common/utils.js

@@ -0,0 +1,18 @@
+module.exports = {
+  getLocFromIndex(text, index) {
+    let line = 1
+    let column = 0
+    let i = 0
+    while (i < index) {
+      if (text[i] === '\n') {
+        line++
+        column = 0
+      } else {
+        column++
+      }
+      i++
+    }
+
+    return { line, column }
+  }
+}

lib/config.js

@@ -1,4 +1,5 @@
 const _ = require('lodash')
+const { RULES } = require('./constants')
 
 module.exports = {
   from(configVals) {
@@ -12,5 +13,31 @@ module.exports = {
 
   getNumber(ruleName, defaultValue) {
     return this.getNumberByPath(`rules["${ruleName}"][1]`, defaultValue)
+  },
+
+  getRulesDisabledByDefault() {
+    const { PRETTIER } = RULES
+    return [PRETTIER]
+  },
+
+  isRuleDisabledByDefault(ruleId) {
+    const rules = module.exports.getRulesDisabledByDefault()
+    return rules.includes(ruleId)
+  },
+
+  validateDisabledByDefault(rulesConfig, rulesToCheck) {
+    const rulesArrayOfObjects = []
+
+    for (const ruleToCheck of rulesToCheck) {
+      const { rule, instance } = ruleToCheck
+
+      const isConfigured = rulesConfig && rulesConfig[rule]
+      const isEnabledByDefault = !module.exports.isRuleDisabledByDefault(rule)
+
+      if (isConfigured || isEnabledByDefault) {
+        rulesArrayOfObjects.push(instance)
+      }
+    }
+    return rulesArrayOfObjects
   }
 }

lib/constants.js

@@ -0,0 +1,6 @@
+module.exports = Object.freeze({
+  RULES: {
+    PRETTIER: 'prettier/prettier',
+    QUOTES: 'quotes'
+  }
+})

lib/index.js

@@ -8,7 +8,7 @@ const Reporter = require('./reporter')
 const TreeListener = require('./tree-listener')
 const checkers = require('./rules/index')
 
-function processStr(inputStr, config = {}) {
+function processStr(inputStr, config = {}, fileName = '') {
   const chars = new antlr4.InputStream(inputStr)
   const lexer = new SolidityLexer(chars)
   const tokens = new antlr4.CommonTokenStream(lexer)
@@ -18,14 +18,14 @@ function processStr(inputStr, config = {}) {
   const tree = parser.sourceUnit()
   const reporter = new Reporter(tokens, config)
 
-  const listener = new TreeListener(checkers(reporter, config))
+  const listener = new TreeListener(checkers(reporter, config, inputStr, fileName))
   antlr4.tree.ParseTreeWalker.DEFAULT.walk(listener, tree)
 
   return reporter
 }
 
 function processFile(file, config) {
-  const report = processStr(fs.readFileSync(file).toString(), config)
+  const report = processStr(fs.readFileSync(file).toString(), config, file)
   report.file = file
 
   return report

lib/rules/base-checker.js

@@ -7,6 +7,10 @@ class BaseChecker {
     this.reporter.error(ctx, ruleId, message)
   }
 
+  errorAt(line, column, ruleId, message) {
+    this.reporter.errorAt(line, column, ruleId, message)
+  }
+
   warn(ctx, ruleId, message) {
     this.reporter.warn(ctx, ruleId, message)
   }

lib/rules/index.js

@@ -4,10 +4,10 @@ const order = require('./order/index')
 const align = require('./align/index')
 const bestPractises = require('./best-practises/index')
 const deprecations = require('./deprecations/index')
-const QuotesChecker = require('./quotes')
+const miscellaneous = require('./miscellaneous/index')
 const configObject = require('./../config')
 
-module.exports = function checkers(reporter, configVals) {
+module.exports = function checkers(reporter, configVals, inputSrc, fileName) {
   const config = configObject.from(configVals)
 
   return [
@@ -17,6 +17,6 @@ module.exports = function checkers(reporter, configVals) {
     ...align(reporter, config),
     ...deprecations(reporter, config),
     ...bestPractises(reporter, config),
-    new QuotesChecker(reporter, config)
+    ...miscellaneous(reporter, config, inputSrc, fileName)
   ]
 }

lib/rules/miscellaneous/index.js

@@ -0,0 +1,20 @@
+const Prettier = require('./prettier')
+const QuotesChecker = require('./quotes')
+const { RULES } = require('../../constants')
+
+module.exports = function checkers(reporter, config, inputSrc, fileName) {
+  const { rules, validateDisabledByDefault } = config
+
+  const rulesToCheck = [
+    {
+      rule: RULES.QUOTES,
+      instance: new QuotesChecker(reporter, config)
+    },
+    {
+      rule: RULES.PRETTIER,
+      instance: new Prettier(reporter, config, inputSrc, fileName)
+    }
+  ]
+
+  return validateDisabledByDefault(rules, rulesToCheck)
+}

lib/rules/miscellaneous/prettier.js

@@ -0,0 +1,71 @@
+const { showInvisibles, generateDifferences } = require('prettier-linter-helpers')
+const { getLocFromIndex } = require('../../common/utils')
+const BaseChecker = require('../base-checker')
+const { RULES } = require('../../constants')
+
+const { INSERT, DELETE, REPLACE } = generateDifferences
+
+class Prettier extends BaseChecker {
+  constructor(reporter, config, inputSrc, fileName) {
+    super(reporter)
+    this.inputSrc = inputSrc
+    this.fileName = fileName
+  }
+
+  enterSourceUnit(ctx) {
+    try {
+      // Check for optional dependencies with the try catch
+      // Prettier is expensive to load, so only load it if needed.
+      const prettier = require('prettier')
+
+      const formatted = prettier.format(this.inputSrc, {
+        filepath: this.fileName,
+        plugins: ['prettier-plugin-solidity']
+      })
+
+      const differences = generateDifferences(this.inputSrc, formatted)
+
+      differences.forEach(difference => {
+        let loc = null
+        switch (difference.operation) {
+          case INSERT:
+            loc = getLocFromIndex(this.inputSrc, difference.offset)
+            this.errorAt(
+              loc.line,
+              loc.column,
+              RULES.PRETTIER,
+              `Insert ${showInvisibles(difference.insertText)}`
+            )
+            break
+          case DELETE:
+            loc = getLocFromIndex(this.inputSrc, difference.offset)
+            this.errorAt(
+              loc.line,
+              loc.column,
+              RULES.PRETTIER,
+              `Delete ${showInvisibles(difference.deleteText)}`
+            )
+            break
+          case REPLACE:
+            loc = getLocFromIndex(this.inputSrc, difference.offset)
+            this.errorAt(
+              loc.line,
+              loc.column,
+              RULES.PRETTIER,
+              `Replace ${showInvisibles(difference.deleteText)} with ${showInvisibles(
+                difference.insertText
+              )}`
+            )
+            break
+          default:
+          // A switch must have a default
+        }
+      })
+    } catch (e) {
+      console.error(e)
+      process.exit(1)
+    }
+  }
+}
+
+module.exports = Prettier

lib/rules/quotes.js → lib/rules/miscellaneous/quotes.js

@@ -1,4 +1,5 @@
-const BaseChecker = require('./base-checker')
+const BaseChecker = require('../base-checker')
+const { RULES } = require('../../constants')
 
 class QuotesChecker extends BaseChecker {
   constructor(reporter, config) {
@@ -40,7 +41,7 @@ class QuotesChecker extends BaseChecker {
   }
 
   _error(ctx) {
-    this.error(ctx, 'quotes', `Use ${this.quoteType} quotes for string literals`)
+    this.error(ctx, RULES.QUOTES, `Use ${this.quoteType} quotes for string literals`)
   }
 }
 

package.json

@@ -31,9 +31,11 @@
     "antlr4": "4.7.1",
     "commander": "2.18.0",
     "eslint": "^5.6.0",
+    "fast-diff": "^1.1.2",
     "glob": "7.1.3",
     "ignore": "^4.0.6",
-    "lodash": "^4.17.11"
+    "lodash": "^4.17.11",
+    "prettier-linter-helpers": "^1.0.0"
   },
   "devDependencies": {
     "assert": "1.4.1",
@@ -44,7 +46,10 @@
     "eslint-plugin-prettier": "^2.6.2",
     "mocha": "^5.2.0",
     "mocha-lcov-reporter": "1.3.0",
-    "nyc": "^13.0.1",
-    "prettier": "^1.14.3"
+    "nyc": "^13.0.1"
+  },
+  "optionalDependencies": {
+    "prettier": "^1.14.3",
+    "prettier-plugin-solidity": "^1.0.0-alpha.4"
   }
 }

test/common/configs.js

@@ -7,4 +7,21 @@ function noIndent() {
   }
 }
 
-module.exports = { noIndent }
+function prettier() {
+  return {
+    rules: {
+      'prettier/prettier': ['error'],
+      indent: false,
+      'no-empty-blocks': false,
+      'two-lines-top-level-separator': false,
+      'state-visibility': false,
+      'separate-by-one-line-in-contract': false,
+      'const-name-snakecase': false,
+      'func-visibility': false,
+      'compiler-fixed': false,
+      'contract-name-camelcase': false,
+      quotes: false
+    }
+  }
+}
+module.exports = { noIndent, prettier }

test/common/contract-builder.js

@@ -21,4 +21,13 @@ function multiLine(...args) {
   return args.join('\n')
 }
 
-module.exports = { contractWith, funcWith, multiLine }
+function contractWithPrettier(code) {
+  return `pragma solidity 0.4.4;
+
+contract A {
+  ${code}
+}
+`
+}
+
+module.exports = { contractWith, funcWith, multiLine, contractWithPrettier }