Switch integration test script to be in JS

This allows us to do more clear checks on the errors returned from
eslint. The sample projects eslintrc is also updated to "allowComments"

Author: azeemba

examples/.eslintrc

@@ -7,9 +7,9 @@
     },
     "overrides": [
         {
-            "files": ["samples/jsonc.json"],
+            "files": ["samples/json-with-comments.json"],
             "rules": {
-                "json/json": ["warn", {"allowComments": true}]
+                "json/*": ["warn", {"allowComments": true}]
             }
         }
     ]

examples/integration-test.js

@@ -0,0 +1,82 @@
+#!/usr/bin/env node
+
+const { execFileSync }= require('child_process');
+const assert = require('assert');
+
+function get_lint_results(filename) {
+    let cmd_args = ['-f', 'json', filename];
+    let lint_results = [];
+    try {
+        let results = execFileSync('eslint', cmd_args, {encoding: 'utf8', stdio: 'pipe'})
+        lint_results = JSON.parse(results)
+    }
+    catch (e) {
+        if (e.status !== 1 && e.status !== 0) {
+            console.error("The lint command itself failed", e.status);
+            throw e;
+        }
+        lint_results = JSON.parse(e.stdout)
+    }
+    return lint_results
+}
+
+function sum_by_rule_id(lint_results) {
+    error_count_by_rule_id = {}
+    warning_count_by_rule_id = {}
+    for (file_result of lint_results) {
+        for (message of file_result.messages) {
+            let counter = error_count_by_rule_id;
+            if (message.severity === 1)  {
+                counter = warning_count_by_rule_id;
+            }
+            if (counter[message.ruleId]) {
+                counter[message.ruleId]++;
+            }
+            else {
+                counter[message.ruleId] = 1;
+            }
+        }
+    }
+    return {"errors": error_count_by_rule_id, "warnings": warning_count_by_rule_id};
+} 
+
+// counts is an object mapping ruleIds to counts
+// expected_array is al ist of expected ruleIds (can have repeated ruleIds)
+function match_count_by_expectation(counts, expected_array) {
+    for (rule_id of expected_array) {
+        assert(counts[rule_id], `${rule_id} violation not found`);
+        counts[rule_id]--;
+    }
+    for (rule_id in counts) {
+        assert(counts[rule_id] == 0, `${rule_id} had an unexpected occurence`);
+    }
+}
+
+function validate_file_by_rules(filename, expected_errors=[], expected_warnings=[]) {
+    lint_results = get_lint_results(filename);
+    counts_by_rule_id = sum_by_rule_id(lint_results)
+
+    error_counts = counts_by_rule_id.errors
+    match_count_by_expectation(error_counts, expected_errors)
+    warning_counts = counts_by_rule_id.warnings
+    match_count_by_expectation(warning_counts, expected_warnings)
+}
+
+function validate_files_by_totals(filename, error_totals, warning_totals) {
+    lint_results = get_lint_results(filename);
+    lint_result = lint_results[0]
+    assert(lint_result.errorCount === error_totals,
+        `${filename} has unexpected number of errors`);
+    assert(lint_result.warningCount === warning_totals,
+        `${filename} has unexpected number of warnings`);
+}
+
+validate_file_by_rules('samples/good-json.json', [], []);
+validate_file_by_rules('samples/duplicate-keys.json',
+    ['json/duplicate-key', 'json/duplicate-key'], [])
+validate_file_by_rules('samples/whole-mess.json',
+    ['json/duplicate-key', 'json/duplicate-key', 'json/trailing-comma'],
+    ['json/*']);
+validate_file_by_rules('samples/json-with-comments.json', [], [])
+
+validate_files_by_totals('samples/wrong-syntax.json', 0, 1)

examples/integration-test.sh

@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "lint": "eslint",
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "node integration-test.js"
   },
   "keywords": [],
   "license": "ISC",

examples/package.json

@@ -17,7 +17,7 @@
   "scripts": {
     "test": "mocha",
     "lint": "eslint lib test",
-    "integration-tests": "(cd examples && ./integration-test.sh)"
+    "integration-tests": "(cd examples && npm run test)"
   },
   "repository": {
     "type": "git",