Add eslint setup (#80)

* Add .npmrc to disable package-lock.json so npm i doesn't create it at every opportunity

* Add .editorconfig reflecting the current formatting

* Add eslint

* Add lint npm script

* Run lint with node.js 12 on CI via a build matrix

* Mark define (AMD) as a global

* Add breaks to prevent switch fallthrough on unknown selectors

Should probably also add default cases to prevent silently ignoring
unknown selectors, but this is at least better than falling through.

* Remove unused function parameter

* Add .eslintignore to avoid checking /parser.js (generated)

* Remove unused dependencies in test files

* Tidy up .eslintrc.json

* Disable the no-unused-vars rule in a file where having esprima around is useful

* Fix accidental global vars

* Also build with node.js 4, 6, 8, 10, 12 and latest

#74 (comment)

* OCD: Put node.js versions in chronological order

* Don't run with the latest node

#80 (comment)

* Throw on unknown selector value type

#80 (comment)

.editorconfig

@@ -0,0 +1,12 @@
+# This file is for unifying the coding style for different editors and IDEs
+# editorconfig.org
+
+root = true
+
+[*]
+end_of_line = lf
+charset = utf-8
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 4

.eslintignore

@@ -0,0 +1,2 @@
+# Generated file:
+/parser.js

.eslintrc.json

@@ -0,0 +1,18 @@
+{
+    "env": {
+        "browser": true,
+        "commonjs": true,
+        "es6": true,
+        "node": true
+    },
+    "extends": "eslint:recommended",
+    "globals": {
+        "Atomics": "readonly",
+        "SharedArrayBuffer": "readonly",
+        "define": "readonly"
+    },
+    "parserOptions": {
+        "ecmaVersion": 2018
+    },
+    "rules": {}
+}

.npmrc

@@ -0,0 +1 @@
+package-lock = false

.travis.yml

@@ -1,7 +1,18 @@
 sudo: false
 language: node_js
 node_js:
-  - "iojs"
-  - "0.12"
-  - "0.11"
   - "0.10"
+  - "0.11"
+  - "0.12"
+  - "iojs"
+  - 4
+  - 6
+  - 8
+  - 10
+  - 12
+
+matrix:
+  include:
+    - name: Lint
+      node_js: 12
+      script: npm run lint

esquery.js

@@ -128,25 +128,26 @@
                                 case 'literal': return '' + selector.value.value === '' + p;
                                 case 'type': return selector.value.value === typeof p;
                             }
+                            throw new Error("Unknown selector value type: " + selector.value.type);
                         case '!=':
                             switch (selector.value.type) {
                                 case 'regexp': return !selector.value.value.test(p);
                                 case 'literal': return '' + selector.value.value !== '' + p;
                                 case 'type': return selector.value.value !== typeof p;
                             }
+                            throw new Error("Unknown selector value type: " + selector.value.type);
                         case '<=': return p <= selector.value.value;
                         case '<': return p < selector.value.value;
                         case '>': return p > selector.value.value;
                         case '>=': return p >= selector.value.value;
                     }
-
+                    break;
                 case 'sibling':
                     return matches(node, selector.right, ancestry) &&
                         sibling(node, selector.left, ancestry, LEFT_SIDE) ||
                         selector.left.subject &&
                         matches(node, selector.left, ancestry) &&
                         sibling(node, selector.right, ancestry, RIGHT_SIDE);
-
                 case 'adjacent':
                     return matches(node, selector.right, ancestry) &&
                         adjacent(node, selector.left, ancestry, LEFT_SIDE) ||
@@ -156,7 +157,7 @@
 
                 case 'nth-child':
                     return matches(node, selector.right, ancestry) &&
-                        nthChild(node, ancestry, function (length) {
+                        nthChild(node, ancestry, function () {
                             return selector.index.value - 1;
                         });
 

package.json

@@ -12,7 +12,8 @@
     "README.md"
   ],
   "scripts": {
-    "test": "node node_modules/jstestr/bin/jstestr.js path=tests"
+    "test": "node node_modules/jstestr/bin/jstestr.js path=tests",
+    "lint": "eslint ."
   },
   "repository": {
     "type": "git",
@@ -25,10 +26,11 @@
     "query"
   ],
   "devDependencies": {
-    "jstestr": ">=0.4",
-    "pegjs": "~0.7.0",
     "commonjs-everywhere": "~0.9.4",
-    "esprima": "~1.1.1"
+    "eslint": "^6.8.0",
+    "esprima": "~1.1.1",
+    "jstestr": ">=0.4",
+    "pegjs": "~0.7.0"
   },
   "license": "BSD-3-Clause",
   "engines": {

tests/fixtures/allClasses.js

@@ -1,3 +1,4 @@
+// eslint-disable-next-line no-unused-vars
 define(["esprima"], function (esprima) {
 
     // return esprima.parse("function a(){ [a] = () => 0; new.target; `test`; `hello,${name}`; }");

tests/queryAttribute.js

@@ -222,6 +222,24 @@ define([
                 conditional.body[1].test.left.right,
                 conditional.body[1].alternate.test
             ], matches);
+        },
+
+        "unknown type": function () {
+            assert.doesThrow(Error, function () {
+                esquery.match(forLoop, {
+                    type: 'attribute',
+                    name: 'foo',
+                    operator: '=',
+                    value: { type: 'foobar' } });
+            });
+
+            assert.doesThrow(Error, function () {
+                esquery.match(forLoop, {
+                    type: 'attribute',
+                    name: 'foo',
+                    operator: '!=',
+                    value: { type: 'foobar' } });
+            });
         }
     });
 });

tests/queryComplex.js

@@ -6,9 +6,8 @@ define([
     "./fixtures/conditional",
     "./fixtures/forLoop",
     "./fixtures/simpleFunction",
-    "./fixtures/simpleProgram",
-    "./fixtures/nestedFunctions"
-], function (esquery, assert, test, conditional, forLoop, simpleFunction, simpleProgram, nestedFunctions) {
+    "./fixtures/simpleProgram"
+], function (esquery, assert, test, conditional, forLoop, simpleFunction, simpleProgram) {
 
     test.defineSuite("Complex selector query", {
 

tests/queryCompound.js

@@ -3,11 +3,8 @@ define([
     "esquery",
     "jstestr/assert",
     "jstestr/test",
-    "./fixtures/conditional",
-    "./fixtures/forLoop",
-    "./fixtures/simpleFunction",
-    "./fixtures/simpleProgram"
-], function (esquery, assert, test, conditional, forLoop, simpleFunction, simpleProgram) {
+    "./fixtures/conditional"
+], function (esquery, assert, test, conditional) {
 
     test.defineSuite("Compound query", {
 

tests/queryNot.js

@@ -44,7 +44,7 @@ define([
                     kind: "var"
                 }]
             };
-            matches = esquery(program, ":not([value=1])");
+            var matches = esquery(program, ":not([value=1])");
 
             assert.contains([
                 program,

tests/queryWildcard.js

@@ -49,7 +49,7 @@ define([
                     kind: "var"
                 }]
             };
-            matches = esquery(program, "*");
+            var matches = esquery(program, "*");
 
             assert.contains([
                 program,