Continue running tests on failure. Print failures.

scripts/test-failure-collector.js

@@ -0,0 +1,69 @@
+/*
+ * Used to collect test failures in a file. Use by specifying --file to Mocha.
+ *
+ * See https://mochajs.org/#command-line-usage
+ */
+
+const path = require('path');
+const projectRoot = path.normalize(path.join(__dirname, '..'));
+const outputLog = path.join(projectRoot, '.test-failures.log');
+
+const red = function(string) {
+  return `\x1b[31m${string}\x1b[0m`;
+};
+
+const green = function(string) {
+  return `\x1b[32m${string}\x1b[0m`;
+};
+
+const dim = function(string) {
+  return `\x1b[2m${string}\x1b[0m`;
+};
+
+// Mapping of test file name to array of failing tests.
+const failuresPerFile = {};
+
+afterEach(function () {
+  if (this.currentTest.state === "failed") {
+    failuresPerFile[this.currentTest.file] = failuresPerFile[this.currentTest.file] || [];
+    failuresPerFile[this.currentTest.file].push(this.currentTest);
+  }
+});
+
+after(function () {
+  if (Object.keys(failuresPerFile).length === 0) return;
+
+  const fs = require('fs')
+  const logger = fs.createWriteStream(outputLog, { flags: 'a' });
+  const writeLine = (line) => logger.write(`${line}\n`);
+
+  for (let file in failuresPerFile) {
+    const failures = failuresPerFile[file];
+
+    // Remove project root from file path to keep log lines shorter.
+    if (file.startsWith(projectRoot)) {
+      file = file.substr(projectRoot.length + 1, file.length - projectRoot.length - 1)
+    }
+
+    // Print each failure.
+    failures.forEach(function (failure, i) {
+      const stack = failure.err.stack.split('\n');
+      writeLine(`${file}:  ${i + 1}\) ${failure.title}:`);
+      writeLine(`${file}:`);
+      writeLine(`${file}:      ${red(stack[0].trim())}`);
+      writeLine(`${file}:      ${green('+ expected')} ${red('- actual')}`);
+      writeLine(`${file}:`);
+      writeLine(`${file}:      ${red("-" + failure.err.actual)}`);
+      writeLine(`${file}:      ${green("+" + failure.err.expected)}`);
+      writeLine(`${file}:`);
+      stack.slice(1).forEach(function (stackLine) {
+        writeLine(`${file}:      ${dim(stackLine.trim())}`);
+      });
+      if (i < failures.length - 1) {
+        writeLine(`${file}:`);
+      }
+    });
+  }
+
+  logger.end();
+});