feat: add special message for bad indentation (#53744)

client/i18n/locales/english/translations.json

@@ -376,6 +376,7 @@
     "tests-completed": "// tests completed",
     "console-output": "// console output",
     "syntax-error": "Your code raised an error before any tests could run. Please fix it and try again.",
+    "indentation-error": "Your code has an indentation error. You may need to add 'pass' on a new line to form a valid block of code.",
     "sign-in-save": "Sign in to save your progress",
     "download-solution": "Download my solution",
     "download-results": "Download my results",

client/src/templates/Challenges/redux/execute-challenge-saga.js

@@ -209,7 +209,7 @@ function* executeTests(testRunner, tests, testTimeout = 5000) {
         throw err;
       }
     } catch (err) {
-      const { actual, expected, syntaxError } = err;
+      const { actual, expected, errorType } = err;
 
       newTest.message = text
         .replace('--fcc-expected--', expected)
@@ -217,14 +217,18 @@ function* executeTests(testRunner, tests, testTimeout = 5000) {
       if (err === 'timeout') {
         newTest.err = 'Test timed out';
         newTest.message = `${newTest.message} (${newTest.err})`;
-      } else if (syntaxError) {
-        newTest.err = 'syntax error';
-        newTest.message = `<p>${i18next.t('learn.syntax-error')}</p>`;
+      } else if (errorType) {
+        const msgKey =
+          errorType === 'indentation'
+            ? 'learn.indentation-error'
+            : 'learn.syntax-error';
+        newTest.message = `<p>${i18next.t(msgKey)}</p>`;
       } else {
         const { message, stack } = err;
         newTest.err = message + '\n' + stack;
         newTest.stack = stack;
       }
+      console.log('newTest', newTest);
       yield put(updateConsole(newTest.message));
     } finally {
       testResults.push(newTest);

tools/client-plugins/browser-scripts/python-test-evaluator.ts

@@ -1,7 +1,7 @@
 // We have to specify pyodide.js because we need to import that file (not .mjs)
 // and 'import' defaults to .mjs
 import { loadPyodide, type PyodideInterface } from 'pyodide/pyodide.js';
-import type { PyProxy } from 'pyodide/ffi';
+import type { PyProxy, PythonError } from 'pyodide/ffi';
 import pkg from 'pyodide/package.json';
 import * as helpers from '@freecodecamp/curriculum-helpers';
 import chai from 'chai';
@@ -135,17 +135,22 @@ input = __inputGen(${JSON.stringify(input ?? [])})
     // available to the test.
     try {
       runPython(code);
-    } catch (err) {
-      // We don't, yet, want user code to raise exceptions. When they do, we
-      // count this as a failing test.
-      ctx.postMessage({
+    } catch (e) {
+      const err = e as PythonError;
+
+      // Quite a lot of lessons can easily lead users to write code that has
+      // indentation errors. In these cases we want to provide a more helpful
+      // error message. For other errors, we can just provide the standard
+      // message.
+      const errorType =
+        err.type === 'IndentationError' ? 'indentation' : 'other';
+      return ctx.postMessage({
         err: {
-          message: (err as Error).message,
-          stack: (err as Error).stack,
-          syntaxError: true
+          message: err.message,
+          stack: err.stack,
+          errorType
         }
       });
-      return;
     }
     // TODO: remove the next line, creating __locals, once all the tests access
     // variables directly.