[pypy-commit] pypy faster-rstruct-2: add direct tests for the various pack() functions in rstruct

[antocuni]

Author: Antonio Cuni <anto.cuni at gmail.com>
Branch: faster-rstruct-2
Changeset: r91225:a99c31346a82
Date: 2017-05-10 11:06 +0200
http://bitbucket.org/pypy/pypy/changeset/a99c31346a82/

Log:	add direct tests for the various pack() functions in rstruct

diff --git a/rpython/rlib/rstruct/test/test_pack.py b/rpython/rlib/rstruct/test/test_pack.py
new file mode 100644
--- /dev/null
+++ b/rpython/rlib/rstruct/test/test_pack.py
@@ -0,0 +1,69 @@
+import pytest
+from rpython.rlib.rstruct import standardfmttable
+from rpython.rlib.mutbuffer import MutableStringBuffer
+import struct
+
+class FakeFormatIter(object):
+
+    def __init__(self, bigendian, value):
+        from rpython.rlib.rstring import StringBuilder
+        self.value = value
+        self.bigendian = bigendian
+        self.result = StringBuilder(8)
+
+    def _accept_arg(self):
+        return self.value
+
+    def __getattr__(self, name):
+        if name.startswith('accept_'):
+            return self._accept_arg
+        raise AttributeError(name)
+
+
+class BaseTestPack(object):
+    """
+    These test tests only the various pack_* functions, individually.  There
+    is no RPython interface to them, as for now they are used only to
+    implement struct.pack in pypy/module/struct
+    """
+
+    endianess = None
+    fmttable = standardfmttable.standard_fmttable
+
+    def mypack(self, fmt, value):
+        bigendian = self.endianess == '>'
+        fake_fmtiter = FakeFormatIter(bigendian, value)
+        attrs = self.fmttable[fmt]
+        pack = attrs['pack']
+        pack(fake_fmtiter)
+        return fake_fmtiter.result.build()
+
+    def check(self, fmt, value):
+        expected = struct.pack(self.endianess+fmt, value)
+        got = self.mypack(fmt, value)
+        assert got == expected
+
+    def test_pack_int(self):
+        self.check('b', 42)
+        self.check('B', 242)
+        self.check('h', 32767)
+        self.check('H', 32768)
+        self.check("i", 0x41424344)
+        self.check("i", -3)
+        self.check("i", -2147483648)
+        self.check("I", 0x81424344)
+        self.check("q", 0x4142434445464748)
+        self.check("q", -0x41B2B3B4B5B6B7B8)
+        self.check("Q", 0x8142434445464748)
+
+    def test_pack_ieee(self):
+        self.check('f', 123.456)
+        self.check('d', 123.456789)
+
+
+class TestPackLittleEndian(BaseTestPack):
+    endianess = '<'
+
+
+class TestPackBigEndian(BaseTestPack):
+    endianess = '>'