Merge tag 'dm-pull-9jul19-take2' of https://gitlab.denx.de/u-boot/custodians/u-boot-dm

[oweals/u-boot.git] / tools / binman / elf_test.py

diff --git a/tools/binman/elf_test.py b/tools/binman/elf_test.py
index fb6e451cf0ec181070d9c4bea3ffb33a4fceac50..42d94cbbbe28bcd9a1e03f4315b9e1ff876218b3 100644 (file)
--- a/tools/binman/elf_test.py
+++ b/tools/binman/elf_test.py
@@ -4,43 +4,37 @@
 #
 # Test for the elf module
 
-from contextlib import contextmanager
 import os
 import sys
 import unittest
 
-try:
-  from StringIO import StringIO
-except ImportError:
-  from io import StringIO
-
 import elf
+import test_util
+import tools
 
 binman_dir = os.path.dirname(os.path.realpath(sys.argv[0]))
 
-# Use this to suppress stdout/stderr output:
-# with capture_sys_output() as (stdout, stderr)
-#   ...do something...
-@contextmanager
-def capture_sys_output():
-  capture_out, capture_err = StringIO(), StringIO()
-  old_out, old_err = sys.stdout, sys.stderr
-  try:
-    sys.stdout, sys.stderr = capture_out, capture_err
-    yield capture_out, capture_err
-  finally:
-    sys.stdout, sys.stderr = old_out, old_err
-
 
 class FakeEntry:
+    """A fake Entry object, usedfor testing
+
+    This supports an entry with a given size.
+    """
     def __init__(self, contents_size):
         self.contents_size = contents_size
-        self.data = 'a' * contents_size
+        self.data = tools.GetBytes(ord('a'), contents_size)
 
     def GetPath(self):
         return 'entry_path'
 
+
 class FakeSection:
+    """A fake Section object, used for testing
+
+    This has the minimum feature set needed to support testing elf functions.
+    A LookupSymbol() function is provided which returns a fake value for amu
+    symbol requested.
+    """
     def __init__(self, sym_value=1):
         self.sym_value = sym_value
 
@@ -48,15 +42,23 @@ class FakeSection:
         return 'section_path'
 
     def LookupSymbol(self, name, weak, msg):
+        """Fake implementation which returns the same value for all symbols"""
         return self.sym_value
 
+
 class TestElf(unittest.TestCase):
+    @classmethod
+    def setUpClass(self):
+        tools.SetInputDirs(['.'])
+
     def testAllSymbols(self):
+        """Test that we can obtain a symbol from the ELF file"""
         fname = os.path.join(binman_dir, 'test', 'u_boot_ucode_ptr')
         syms = elf.GetSymbols(fname, [])
         self.assertIn('.ucode', syms)
 
     def testRegexSymbols(self):
+        """Test that we can obtain from the ELF file by regular expression"""
         fname = os.path.join(binman_dir, 'test', 'u_boot_ucode_ptr')
         syms = elf.GetSymbols(fname, ['ucode'])
         self.assertIn('.ucode', syms)
@@ -66,6 +68,7 @@ class TestElf(unittest.TestCase):
         self.assertIn('.ucode', syms)
 
     def testMissingFile(self):
+        """Test that a missing file is detected"""
         entry = FakeEntry(10)
         section = FakeSection()
         with self.assertRaises(ValueError) as e:
@@ -74,6 +77,7 @@ class TestElf(unittest.TestCase):
                       str(e.exception))
 
     def testOutsideFile(self):
+        """Test a symbol which extends outside the entry area is detected"""
         entry = FakeEntry(10)
         section = FakeSection()
         elf_fname = os.path.join(binman_dir, 'test', 'u_boot_binman_syms')
@@ -83,6 +87,11 @@ class TestElf(unittest.TestCase):
                       'is a', str(e.exception))
 
     def testMissingImageStart(self):
+        """Test that we detect a missing __image_copy_start symbol
+
+        This is needed to mark the start of the image. Without it we cannot
+        locate the offset of a binman symbol within the image.
+        """
         entry = FakeEntry(10)
         section = FakeSection()
         elf_fname = os.path.join(binman_dir, 'test', 'u_boot_binman_syms_bad')
@@ -90,6 +99,11 @@ class TestElf(unittest.TestCase):
                          None)
 
     def testBadSymbolSize(self):
+        """Test that an attempt to use an 8-bit symbol are detected
+
+        Only 32 and 64 bits are supported, since we need to store an offset
+        into the image.
+        """
         entry = FakeEntry(10)
         section = FakeSection()
         elf_fname = os.path.join(binman_dir, 'test', 'u_boot_binman_syms_size')
@@ -99,18 +113,25 @@ class TestElf(unittest.TestCase):
                       str(e.exception))
 
     def testNoValue(self):
+        """Test the case where we have no value for the symbol
+
+        This should produce -1 values for all thress symbols, taking up the
+        first 16 bytes of the image.
+        """
         entry = FakeEntry(20)
         section = FakeSection(sym_value=None)
         elf_fname = os.path.join(binman_dir, 'test', 'u_boot_binman_syms')
         syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
-        self.assertEqual(chr(255) * 16 + 'a' * 4, entry.data)
+        self.assertEqual(tools.GetBytes(255, 16) + tools.GetBytes(ord('a'), 4),
+                                                                  entry.data)
 
     def testDebug(self):
+        """Check that enabling debug in the elf module produced debug output"""
         elf.debug = True
         entry = FakeEntry(20)
         section = FakeSection()
         elf_fname = os.path.join(binman_dir, 'test', 'u_boot_binman_syms')
-        with capture_sys_output() as (stdout, stderr):
+        with test_util.capture_sys_output() as (stdout, stderr):
             syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
         elf.debug = False
         self.assertTrue(len(stdout.getvalue()) > 0)