New: no-unused-modules rule - added default src, more comprehensive…

… sanity checks

Signed-off-by: René Fermann <rene.fermann@gmx.de>

src/rules/no-unused-modules.js

@@ -6,10 +6,17 @@
 
 import Exports from '../ExportMap'
 import { makeOptionsSchema } from 'eslint-module-utils/moduleVisitor'
-import { listFilesToProcess } from 'eslint/lib/util/glob-util'
 import resolve from 'eslint-module-utils/resolve'
 import docsUrl from '../docsUrl'
 
+// eslint/lib/util/glob-util has been moved to eslint/lib/util/glob-utils with version 5.3
+let listFilesToProcess
+try {
+  listFilesToProcess = require('eslint/lib/util/glob-util').listFilesToProcess
+} catch (err) {
+  listFilesToProcess = require('eslint/lib/util/glob-utils').listFilesToProcess
+}
+
 const EXPORT_DEFAULT_DECLARATION = 'ExportDefaultDeclaration'
 const EXPORT_NAMED_DECLARATION = 'ExportNamedDeclaration'
 const IMPORT_DECLARATION = 'ImportDeclaration' 
@@ -113,6 +120,13 @@ const determineUsage = () => {
   })
 }
 
+const getSrc = src => {
+  if (src) {
+    return src
+  }
+  return [process.cwd()]
+}
+
 /**
  * prepare the lists of existing imports and exports - should only be executed once at
  * the start of a new eslint run
@@ -121,32 +135,38 @@ const doPreparation = (src, ignore, context) => {
   const { id } = context
 
   // do some sanity checks
-  if (!Array.isArray(src)) {
+  if (typeof src !== UNDEFINED && !Array.isArray(src)) {
     throw new Error(`Rule ${id}: src option must be an array`)
   }
 
-  if (!Array.isArray(ignore)) {
+  if (typeof ignore !== UNDEFINED && !Array.isArray(ignore)) {
     throw new Error(`Rule ${id}: ignore option must be an array`)
   }
 
-  if (src.length < 1) {
-    throw new Error(`Rule ${id}: src option must be defined`)
-  }
-
   // no empty patterns for paths, as this will cause issues during path resolution
-  src.forEach(file => {
-    if (file.length < 1) {
-      throw new Error(`Rule ${id}: src option must not contain empty strings`)
-    }
-  })
-
-  ignore.forEach(file => {
-    if (file.length < 1) {
-      throw new Error(`Rule ${id}: ignore option must not contain empty strings`)
-    }
-  })
+  if (src) {
+    src.forEach(file => {
+      if (typeof file !== 'string') {
+        throw new Error(`Rule ${id}: src option must not contain values other than strings`)
+      }
+      if (file.length < 1) {
+        throw new Error(`Rule ${id}: src option must not contain empty strings`)
+      }
+    })
+  }
+
+  if (ignore) {
+    ignore.forEach(file => {
+      if (typeof file !== 'string') {
+        throw new Error(`Rule ${id}: ignore option must not contain values other than strings`)
+      }
+      if (file.length < 1) {
+        throw new Error(`Rule ${id}: ignore option must not contain empty strings`)
+      }
+    })
+  }
 
-  const srcFiles = resolveFiles(src, ignore)
+  const srcFiles = resolveFiles(getSrc(src), ignore)
   prepareImportsAndExports(srcFiles, context)
   determineUsage()  
   preparationDone = true
@@ -168,6 +188,7 @@ const newDefaultImportExists = specifiers => {
 
 module.exports = {
   doPreparation,
+  getSrc,
   meta: {
     docs: { url: docsUrl('no-unused-modules') },
     schema: [

tests/src/rules/no-unused-modules.js

@@ -1,9 +1,10 @@
 import { test, testFilePath } from '../utils'
 
 import { RuleTester } from 'eslint'
-import { expect } from 'chai';
+import { expect } from 'chai'
 
 const doPreparation = require( '../../../src/rules/no-unused-modules').doPreparation
+const getSrc = require( '../../../src/rules/no-unused-modules').getSrc
 
 const ruleTester = new RuleTester()
     , rule = require('rules/no-unused-modules')
@@ -21,22 +22,46 @@ const unusedExportsOptions = [{
 }]
 
 describe('doPreparation throws correct errors', () => {
-  // const fn = doPreparation()
-  const context = {id: 'no-unused-modules' }
+  const context = { id: 'no-unused-modules' }
   it('should throw an error, if src is not an array', () => {
     expect(doPreparation.bind(doPreparation, null,  null, context)).to.throw(`Rule ${context.id}: src option must be an array`)
   })
   it('should throw an error, if ignore is not an array', () => {
     expect(doPreparation.bind(doPreparation, [], null, context)).to.throw(`Rule ${context.id}: ignore option must be an array`)
   })
-  it('should throw an error, if src is empty', () => {
-    expect(doPreparation.bind(doPreparation, [],  [], context)).to.throw(`Rule ${context.id}: src option must be defined`)
+  it('should throw an error, if src contains empty strings', () => {
+    expect(doPreparation.bind(doPreparation, [''],  [], context)).to.throw(`Rule ${context.id}: src option must not contain empty strings`)
   })
-  it('should throw an error, if src is empty', () => {
-    expect(doPreparation.bind(doPreparation, [""],  [], context)).to.throw(`Rule ${context.id}: src option must not contain empty strings`)
+  it('should throw an error, if src contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, [false],  [], context)).to.throw(`Rule ${context.id}: src option must not contain values other than strings`)
   })
-  it('should throw an error, if src is empty', () => {
-    expect(doPreparation.bind(doPreparation, ["src"],  [""], context)).to.throw(`Rule ${context.id}: ignore option must not contain empty strings`)
+  it('should throw an error, if src contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, [null],  [], context)).to.throw(`Rule ${context.id}: src option must not contain values other than strings`)
+  })
+  it('should throw an error, if src contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, [undefined],  [], context)).to.throw(`Rule ${context.id}: src option must not contain values other than strings`)
+  })
+  it('should throw an error, if ignore contains empty strings', () => {
+    expect(doPreparation.bind(doPreparation, ['src'],  [''], context)).to.throw(`Rule ${context.id}: ignore option must not contain empty strings`)
+  })
+  it('should throw an error, if ignore contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, ['src'],  [false], context)).to.throw(`Rule ${context.id}: ignore option must not contain values other than strings`)
+  })
+  it('should throw an error, if ignore contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, ['src'],  [null], context)).to.throw(`Rule ${context.id}: ignore option must not contain values other than strings`)
+  })
+  it('should throw an error, if ignore contains values other than strings', () => {
+    expect(doPreparation.bind(doPreparation, ['src'],  [undefined], context)).to.throw(`Rule ${context.id}: ignore option must not contain values other than strings`)
+  })
+})
+
+describe('getSrc returns correct source', () => {
+  it('if src is provided', () => {
+    const src = ['file-a.js']
+    expect(getSrc(src)).to.eq(src)
+  })
+  it('if src is not provided', () => {
+    expect(getSrc()).to.eql([process.cwd()])
   })
 })