dtoc: add coverage test for unicode error

Add an additional test to dtoc in order improve the coverage,
specifically to take into account the case of unicode error when
scanning drivers.

Signed-off-by: Walter Lozano <walter.lozano@collabora.com>

tools/dtoc/test_dtoc.py

@@ -13,6 +13,7 @@ import collections
 import os
 import struct
 import sys
+import tempfile
 import unittest
 
 from dtoc import dtb_platdata
@@ -863,3 +864,28 @@ U_BOOT_DEVICE(spl_test2) = {
             self.run_test(['invalid-cmd'], dtb_file, output)
         self.assertIn("Unknown command 'invalid-cmd': (use: struct, platdata)",
                       str(e.exception))
+
+    def testScanDrivers(self):
+        """Test running dtoc with additional drivers to scan"""
+        dtb_file = get_dtb_file('dtoc_test_simple.dts')
+        output = tools.GetOutputFilename('output')
+        with test_util.capture_sys_output() as (stdout, stderr):
+            dtb_platdata.run_steps(['struct'], dtb_file, False, output, True,
+                               [None, '', 'tools/dtoc/dtoc_test_scan_drivers.cxx'])
+
+    def testUnicodeError(self):
+        """Test running dtoc with an invalid unicode file
+
+        To be able to perform this test without adding a weird text file which
+        would produce issues when using checkpatch.pl or patman, generate the
+        file at runtime and then process it.
+        """
+        dtb_file = get_dtb_file('dtoc_test_simple.dts')
+        output = tools.GetOutputFilename('output')
+        driver_fn = '/tmp/' + next(tempfile._get_candidate_names())
+        with open(driver_fn, 'wb+') as df:
+            df.write(b'\x81')
+
+        with test_util.capture_sys_output() as (stdout, stderr):
+            dtb_platdata.run_steps(['struct'], dtb_file, False, output, True,
+                               [driver_fn])