[PATCH v11 2/5] Add tests for pylibfdt

[Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>]

Add a set of tests to cover the functionality in pylibfdt.

Signed-off-by: Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
---

Changes in v11: None
Changes in v10: None
Changes in v9: None
Changes in v8:
- Avoid using hard-coded offsets (ROOT_PROPS)
- Use types.ModuleType instead of type(str)
- Compare exception number instead of using a regex
- Avoid using hard-coded size
- Drop testEndian()
- Move the changes to run_tests.sh to a later commit
- Add comments to testPropertyOffsetExceptions()

Changes in v7:
- Add a test for QUIET_ALL

Changes in v6:
- Adjust tests to avoid checking a hard-coded offset
- Use 0 instead of self.fdt.path_offset('/')
- Adjust the totalsize() test to compare against the file size
- Adjust test result processing to avoid using awk

Changes in v5:
- Adjust tests to match new swig bindings

Changes in v4:
- Drop tests that are no-longer applicable
- Add a get for getprop()

Changes in v3:
- Add some more tests

Changes in v2:
- Update tests for new pylibfdt
- Add a few more tests to increase coverage

 tests/pylibfdt_tests.py | 288 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 288 insertions(+)
 create mode 100644 tests/pylibfdt_tests.py

diff --git a/tests/pylibfdt_tests.py b/tests/pylibfdt_tests.py
new file mode 100644
index 0000000..ae392bb
--- /dev/null
+++ b/tests/pylibfdt_tests.py
@@ -0,0 +1,288 @@
+# pylibfdt - Tests for Flat Device Tree manipulation in Python
+# Copyright (C) 2017 Google, Inc.
+# Written by Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
+#
+# libfdt is dual licensed: you can use it either under the terms of
+# the GPL, or the BSD license, at your option.
+#
+#  a) This library is free software; you can redistribute it and/or
+#     modify it under the terms of the GNU General Public License as
+#     published by the Free Software Foundation; either version 2 of the
+#     License, or (at your option) any later version.
+#
+#     This library is distributed in the hope that it will be useful,
+#     but WITHOUT ANY WARRANTY; without even the implied warranty of
+#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#     GNU General Public License for more details.
+#
+#     You should have received a copy of the GNU General Public
+#     License along with this library; if not, write to the Free
+#     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+#     MA 02110-1301 USA
+#
+# Alternatively,
+#
+#  b) Redistribution and use in source and binary forms, with or
+#     without modification, are permitted provided that the following
+#     conditions are met:
+#
+#     1. Redistributions of source code must retain the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer.
+#     2. Redistributions in binary form must reproduce the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer in the documentation and/or other materials
+#        provided with the distribution.
+#
+#     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+#     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+#     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+#     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+#     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+#     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+#     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+#     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+#     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+#     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+#     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+
+import sys
+import types
+import unittest
+
+sys.path.append('../pylibfdt')
+import libfdt
+from libfdt import FdtException, QUIET_NOTFOUND, QUIET_ALL
+
+def get_err(err_code):
+    """Convert an error code into an error message
+
+    Args:
+        err_code: Error code value (FDT_ERR_...)
+
+    Returns:
+        String error code
+    """
+    return 'pylibfdt error %d: %s' % (-err_code, libfdt.fdt_strerror(-err_code))
+
+def _ReadFdt(fname):
+    """Read a device tree file into an Fdt object, ready for use
+
+    Args:
+        fname: Filename to read from
+
+    Returns:
+        Fdt bytearray suitable for passing to libfdt functions
+    """
+    return libfdt.Fdt(open(fname).read())
+
+class PyLibfdtTests(unittest.TestCase):
+    """Test class for pylibfdt
+
+    Properties:
+        fdt: Device tree file used for testing
+    """
+
+    def setUp(self):
+        """Read in the device tree we use for testing"""
+        self.fdt = _ReadFdt('test_tree1.dtb')
+
+    def GetPropList(self, node_path):
+        """Read a list of properties from a node
+
+        Args:
+            node_path: Full path to node, e.g. '/subnode@1/subsubnode'
+
+        Returns:
+            List of property names for that node, e.g. ['compatible', 'reg']
+        """
+        prop_list = []
+        node = self.fdt.path_offset(node_path)
+        poffset = self.fdt.first_property_offset(node, QUIET_NOTFOUND)
+        while poffset > 0:
+            prop = self.fdt.get_property_by_offset(poffset)
+            prop_list.append(prop.name)
+            poffset = self.fdt.next_property_offset(poffset, QUIET_NOTFOUND)
+        return prop_list
+
+    def testImport(self):
+        """Check that we can import the library correctly"""
+        self.assertEquals(type(libfdt), types.ModuleType)
+
+    def testBadFdt(self):
+        """Check that a filename provided accidentally is not accepted"""
+        with self.assertRaises(FdtException) as e:
+            fdt = libfdt.Fdt('a string')
+        self.assertEquals(e.exception.err, -libfdt.BADMAGIC)
+
+    def testPathOffset(self):
+        """Check that we can find the offset of a node"""
+        self.assertEquals(self.fdt.path_offset('/'), 0)
+        self.assertTrue(self.fdt.path_offset('/subnode@1') > 0)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.path_offset('/wibble')
+        self.assertEquals(e.exception.err, -libfdt.NOTFOUND)
+        self.assertEquals(self.fdt.path_offset('/wibble', QUIET_NOTFOUND),
+                          -libfdt.NOTFOUND)
+
+    def testPropertyOffset(self):
+        """Walk through all the properties in the root node"""
+        offset = self.fdt.first_property_offset(0)
+        self.assertTrue(offset > 0)
+        for i in range(5):
+            next_offset = self.fdt.next_property_offset(offset)
+            self.assertTrue(next_offset > offset)
+            offset = next_offset
+        self.assertEquals(self.fdt.next_property_offset(offset, QUIET_NOTFOUND),
+                          -libfdt.NOTFOUND)
+
+    def testPropertyOffsetExceptions(self):
+        """Check that exceptions are raised as expected"""
+        with self.assertRaises(FdtException) as e:
+            self.fdt.first_property_offset(107)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+
+        # Quieten the NOTFOUND exception and check that a BADOFFSET
+        # exception is still raised.
+        with self.assertRaises(FdtException) as e:
+            self.fdt.first_property_offset(107, QUIET_NOTFOUND)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.next_property_offset(107, QUIET_NOTFOUND)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+
+        # Check that NOTFOUND can be quietened.
+        node = self.fdt.path_offset('/subnode@1/ss1')
+        self.assertEquals(self.fdt.first_property_offset(node, QUIET_NOTFOUND),
+                          -libfdt.NOTFOUND)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.first_property_offset(node)
+        self.assertEquals(e.exception.err, -libfdt.NOTFOUND)
+
+    def testGetName(self):
+        """Check that we can get the name of a node"""
+        self.assertEquals(self.fdt.get_name(0), '')
+        node = self.fdt.path_offset('/subnode@1/subsubnode')
+        self.assertEquals(self.fdt.get_name(node), 'subsubnode')
+
+        with self.assertRaises(FdtException) as e:
+            self.fdt.get_name(-2)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+
+    def testGetPropertyByOffset(self):
+        """Check that we can read the name and contents of a property"""
+        root = 0
+        poffset = self.fdt.first_property_offset(root)
+        prop = self.fdt.get_property_by_offset(poffset)
+        self.assertEquals(prop.name, 'compatible')
+        self.assertEquals(prop.value, 'test_tree1\0')
+
+        with self.assertRaises(FdtException) as e:
+            self.fdt.get_property_by_offset(-2)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+        self.assertEquals(
+                -libfdt.BADOFFSET,
+                self.fdt.get_property_by_offset(-2, [libfdt.BADOFFSET]))
+
+    def testGetProp(self):
+        """Check that we can read the contents of a property by name"""
+        root = self.fdt.path_offset('/')
+        value = self.fdt.getprop(root, "compatible")
+        self.assertEquals(value, 'test_tree1\0')
+        self.assertEquals(-libfdt.NOTFOUND, self.fdt.getprop(root, 'missing',
+                                                             QUIET_NOTFOUND))
+
+        with self.assertRaises(FdtException) as e:
+            self.fdt.getprop(root, 'missing')
+        self.assertEquals(e.exception.err, -libfdt.NOTFOUND)
+
+        node = self.fdt.path_offset('/subnode@1/subsubnode')
+        value = self.fdt.getprop(node, "compatible")
+        self.assertEquals(value, 'subsubnode1\0subsubnode\0')
+
+    def testStrError(self):
+        """Check that we can get an error string"""
+        self.assertEquals(libfdt.strerror(-libfdt.NOTFOUND),
+                          'FDT_ERR_NOTFOUND')
+
+    def testFirstNextSubnodeOffset(self):
+        """Check that we can walk through subnodes"""
+        node_list = []
+        node = self.fdt.first_subnode(0, QUIET_NOTFOUND)
+        while node >= 0:
+            node_list.append(self.fdt.get_name(node))
+            node = self.fdt.next_subnode(node, QUIET_NOTFOUND)
+        self.assertEquals(node_list, ['subnode@1', 'subnode@2'])
+
+    def testFirstNextSubnodeOffsetExceptions(self):
+        """Check except handling for first/next subnode functions"""
+        node = self.fdt.path_offset('/subnode@1/subsubnode', QUIET_NOTFOUND)
+        self.assertEquals(self.fdt.first_subnode(node, QUIET_NOTFOUND),
+                          -libfdt.NOTFOUND)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.first_subnode(node)
+        self.assertEquals(e.exception.err, -libfdt.NOTFOUND)
+
+        node = self.fdt.path_offset('/subnode@1/ss1', QUIET_NOTFOUND)
+        self.assertEquals(self.fdt.next_subnode(node, QUIET_NOTFOUND),
+                          -libfdt.NOTFOUND)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.next_subnode(node)
+        self.assertEquals(e.exception.err, -libfdt.NOTFOUND)
+
+    def testDeleteProperty(self):
+        """Test that we can delete a property"""
+        node_name = '/subnode@1'
+        self.assertEquals(self.GetPropList(node_name),
+                          ['compatible', 'reg', 'prop-int'])
+        node = self.fdt.path_offset('/%s' % node_name)
+        self.assertEquals(self.fdt.delprop(node, 'reg'), 0)
+        self.assertEquals(self.GetPropList(node_name),
+                          ['compatible', 'prop-int'])
+
+    def testHeader(self):
+        """Test that we can access the header values"""
+        self.assertEquals(self.fdt.totalsize(), len(self.fdt._fdt))
+        self.assertEquals(self.fdt.off_dt_struct(), 88)
+
+    def testPack(self):
+        """Test that we can pack the tree after deleting something"""
+        orig_size = self.fdt.totalsize()
+        node = self.fdt.path_offset('/subnode@2', QUIET_NOTFOUND)
+        self.assertEquals(self.fdt.delprop(node, 'prop-int'), 0)
+        self.assertEquals(orig_size, self.fdt.totalsize())
+        self.assertEquals(self.fdt.pack(), 0)
+        self.assertTrue(self.fdt.totalsize() < orig_size)
+
+    def testBadPropertyOffset(self):
+        """Test that bad property offsets are detected"""
+        with self.assertRaises(FdtException) as e:
+            self.fdt.get_property_by_offset(13)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.first_property_offset(3)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+        with self.assertRaises(FdtException) as e:
+            self.fdt.next_property_offset(3)
+        self.assertEquals(e.exception.err, -libfdt.BADOFFSET)
+
+    def testBadPathOffset(self):
+        """Test that bad path names are detected"""
+        with self.assertRaisesRegexp(FdtException, get_err(libfdt.BADPATH)):
+            self.fdt.path_offset('not-present')
+
+    def testQuietAll(self):
+        """Check that exceptions can be masked by QUIET_ALL"""
+        self.assertEquals(-libfdt.NOTFOUND,
+                          self.fdt.path_offset('/missing', QUIET_ALL))
+        self.assertEquals(-libfdt.BADOFFSET,
+                          self.fdt.get_property_by_offset(13, QUIET_ALL))
+        self.assertEquals(-libfdt.BADPATH,
+                          self.fdt.path_offset('missing', QUIET_ALL))
+
+
+if __name__ == "__main__":
+    unittest.main()
-- 
2.12.0.367.g23dc2f6d3c-goog