node: fix #7841 by overlooking the spare sourceline

Signed-off-by: Fedor Indutny <fedor@indutny.com>

src/node.cc

@@ -1396,14 +1396,22 @@ void AppendExceptionLine(Environment* env,
 
   // Print wavy underline (GetUnderline is deprecated).
   for (int i = 0; i < start; i++) {
+    if (sourceline_string[i] == '\0' ||
+        static_cast<size_t>(off) >= sizeof(arrow)) {
+      break;
+    }
     assert(static_cast<size_t>(off) < sizeof(arrow));
     arrow[off++] = (sourceline_string[i] == '\t') ? '\t' : ' ';
   }
   for (int i = start; i < end; i++) {
+    if (sourceline_string[i] == '\0' ||
+        static_cast<size_t>(off) >= sizeof(arrow)) {
+      break;
+    }
     assert(static_cast<size_t>(off) < sizeof(arrow));
     arrow[off++] = '^';
   }
-  assert(static_cast<size_t>(off) < sizeof(arrow) - 1);
+  assert(static_cast<size_t>(off - 1) <= sizeof(arrow) - 1);
   arrow[off++] = '\n';
   arrow[off] = '\0';
 

test/fixtures/throws_error4.js

@@ -0,0 +1,41 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+01234567890123456789012345/**
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789
+01234567890123456789012345678901234567890123456789

test/simple/test-error-reporting.js

@@ -71,6 +71,13 @@ errExec('throws_error3.js', function(err, stdout, stderr) {
 });
 
 
-process.on('exit', function() {
-  assert.equal(3, exits);
+// throw ILLEGAL error
+errExec('throws_error4.js', function(err, stdout, stderr) {
+  assert.ok(/\/\*\*/.test(stderr));
+  assert.ok(/SyntaxError/.test(stderr));
+});
+
+
+process.on('exit', function() {
+  assert.equal(4, exits);
 });