http://scons.tigris.org/issues/show_bug.cgi?id=2345

Comb out all code that supported earlier versions of Python.  Most such
code is in snippets of only a few lines and can be identified by having
a Python version string in it.  Such snippets add up; this combing pass
probably got rid of over 500 lines of code.

4 files changed, 31 insertions, 126 deletions

diff --git a/src/engine/SCons/Node/FS.py b/src/engine/SCons/Node/FS.py
index 3175328..7bae6c1 100644
--- a/src/engine/SCons/Node/FS.py
+++ b/src/engine/SCons/Node/FS.py
@@ -31,8 +31,6 @@ that can be used by scripts or modules looking for the canonical default.
 # 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.
-#
-from __future__ import generators  ### KEEP FOR COMPATIBILITY FIXERS
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
@@ -43,58 +41,7 @@ import shutil
 import stat
 import sys
 import time
-
-try:
-    import codecs
-except ImportError:
-    pass
-else:
-    # TODO(2.2):  Remove when 2.3 becomes the minimal supported version.
-    try:
-        codecs.BOM_UTF8
-    except AttributeError:
-        codecs.BOM_UTF8 = '\xef\xbb\xbf'
-    try:
-        codecs.BOM_UTF16_LE
-        codecs.BOM_UTF16_BE
-    except AttributeError:
-        codecs.BOM_UTF16_LE = '\xff\xfe'
-        codecs.BOM_UTF16_BE = '\xfe\xff'
-
-    # Provide a wrapper function to handle decoding differences in
-    # different versions of Python.  Normally, we'd try to do this in the
-    # compat layer (and maybe it still makes sense to move there?) but
-    # that doesn't provide a way to supply the string class used in
-    # pre-2.3 Python versions with a .decode() method that all strings
-    # naturally have.  Plus, the 2.[01] encodings behave differently
-    # enough that we have to settle for a lowest-common-denominator
-    # wrapper approach.
-    #
-    # Note that the 2.[012] implementations below may be inefficient
-    # because they perform an explicit look up of the encoding for every
-    # decode, but they're old enough (and we want to stop supporting
-    # them soon enough) that it's not worth complicating the interface.
-    # Think of it as additional incentive for people to upgrade...
-    try:
-        ''.decode
-    except AttributeError:
-        # 2.0 through 2.2:  strings have no .decode() method
-        try:
-            codecs.lookup('ascii').decode
-        except AttributeError:
-            # 2.0 and 2.1:  encodings are a tuple of functions, and the
-            # decode() function returns a (result, length) tuple.
-            def my_decode(contents, encoding):
-                return codecs.lookup(encoding)[1](contents)[0]
-        else:
-            # 2.2:  encodings are an object with methods, and the
-            # .decode() method returns just the decoded bytes.
-            def my_decode(contents, encoding):
-                return codecs.lookup(encoding).decode(contents)
-    else:
-        # 2.3 or later:  use the .decode() string method
-        def my_decode(contents, encoding):
-            return contents.decode(encoding)
+import codecs
 
 import SCons.Action
 from SCons.Debug import logInstanceCreation
@@ -2276,8 +2223,6 @@ class File(Base):
     def Dirs(self, pathlist):
         """Create a list of directories relative to the SConscript
         directory of this file."""
-        # TODO(1.5)
-        # return [self.Dir(p) for p in pathlist]
         return [self.Dir(p) for p in pathlist]
 
     def File(self, name):
@@ -2326,38 +2271,24 @@ class File(Base):
             raise
         return contents
 
-    try:
-        import codecs
-    except ImportError:
-        get_text_contents = get_contents
-    else:
-        # This attempts to figure out what the encoding of the text is
-        # based upon the BOM bytes, and then decodes the contents so that
-        # it's a valid python string.
-        def get_text_contents(self):
-            contents = self.get_contents()
-            # The behavior of various decode() methods and functions
-            # w.r.t. the initial BOM bytes is different for different
-            # encodings and/or Python versions.  ('utf-8' does not strip
-            # them, but has a 'utf-8-sig' which does; 'utf-16' seems to
-            # strip them; etc.)  Just side step all the complication by
-            # explicitly stripping the BOM before we decode().
-            if contents.startswith(codecs.BOM_UTF8):
-                contents = contents[len(codecs.BOM_UTF8):]
-                # TODO(2.2):  Remove when 2.3 becomes floor.
-                #contents = contents.decode('utf-8')
-                contents = my_decode(contents, 'utf-8')
-            elif contents.startswith(codecs.BOM_UTF16_LE):
-                contents = contents[len(codecs.BOM_UTF16_LE):]
-                # TODO(2.2):  Remove when 2.3 becomes floor.
-                #contents = contents.decode('utf-16-le')
-                contents = my_decode(contents, 'utf-16-le')
-            elif contents.startswith(codecs.BOM_UTF16_BE):
-                contents = contents[len(codecs.BOM_UTF16_BE):]
-                # TODO(2.2):  Remove when 2.3 becomes floor.
-                #contents = contents.decode('utf-16-be')
-                contents = my_decode(contents, 'utf-16-be')
-            return contents
+    # This attempts to figure out what the encoding of the text is
+    # based upon the BOM bytes, and then decodes the contents so that
+    # it's a valid python string.
+    def get_text_contents(self):
+        contents = self.get_contents()
+        # The behavior of various decode() methods and functions
+        # w.r.t. the initial BOM bytes is different for different
+        # encodings and/or Python versions.  ('utf-8' does not strip
+        # them, but has a 'utf-8-sig' which does; 'utf-16' seems to
+        # strip them; etc.)  Just sidestep all the complication by
+        # explicitly stripping the BOM before we decode().
+        if contents.startswith(codecs.BOM_UTF8):
+            return contents[len(codecs.BOM_UTF8):].decode('utf-8')
+        if contents.startswith(codecs.BOM_UTF16_LE):
+            return contents[len(codecs.BOM_UTF16_LE):].decode('utf-16-le')
+        if contents.startswith(codecs.BOM_UTF16_BE):
+            return contents[len(codecs.BOM_UTF16_BE):].decode('utf-16-be')
+        return contents
 
     def get_content_hash(self):
         """
@@ -3140,7 +3071,7 @@ class FileFinder:
             #    if isinstance(node, Dir) or isinstance(node, Entry):
             #        return node
             #    return None
-            #paths = filter(None, map(filedir_lookup, paths))
+            #paths = [_f for _f in map(filedir_lookup, paths) if _f]
 
             self.default_filedir = filedir
             paths = [_f for _f in map(self.filedir_lookup, paths) if _f]
diff --git a/src/engine/SCons/Node/FSTests.py b/src/engine/SCons/Node/FSTests.py
index 58726d3..7fcec8f 100644
--- a/src/engine/SCons/Node/FSTests.py
+++ b/src/engine/SCons/Node/FSTests.py
@@ -1189,17 +1189,12 @@ class FSTestCase(_tempdirTestCase):
         f1 = fs.File(test.workpath("binary_file"))
         assert f1.get_contents() == "Foo\x1aBar", f1.get_contents()
 
-        try:
-            # TODO(1.5)
-            eval('test_string = u"Foo\x1aBar"')
-        except SyntaxError:
-            pass
-        else:
-            # This tests to make sure we can decode UTF-8 text files.
-            test.write("utf8_file", test_string.encode('utf-8'))
-            f1 = fs.File(test.workpath("utf8_file"))
-            assert eval('f1.get_text_contents() == u"Foo\x1aBar"'), \
-                   f1.get_text_contents()
+        # This tests to make sure we can decode UTF-8 text files.
+        test_string = u"Foo\x1aBar"
+        test.write("utf8_file", test_string.encode('utf-8'))
+        f1 = fs.File(test.workpath("utf8_file"))
+        assert eval('f1.get_text_contents() == u"Foo\x1aBar"'), \
+               f1.get_text_contents()
 
         def nonexistent(method, s):
             try:
@@ -1749,7 +1744,6 @@ class DirTestCase(_tempdirTestCase):
         e = self.fs.Dir(os.path.join('d', 'empty'))
         s = self.fs.Dir(os.path.join('d', 'sub'))
 
-        #TODO(1.5) files = d.get_contents().split('\n')
         files = d.get_contents().split('\n')
 
         assert e.get_contents() == '', e.get_contents()
diff --git a/src/engine/SCons/Node/NodeTests.py b/src/engine/SCons/Node/NodeTests.py
index beb9a31..db699d3 100644
--- a/src/engine/SCons/Node/NodeTests.py
+++ b/src/engine/SCons/Node/NodeTests.py
@@ -19,8 +19,6 @@
 # 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.
-#
-from __future__ import generators  ### KEEP FOR COMPATIBILITY FIXERS
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
@@ -1280,15 +1278,8 @@ class NodeListTestCase(unittest.TestCase):
 
         l = [1]
         ul = collections.UserList([2])
-        try:
-            l.extend(ul)
-        except TypeError:
-            # An older version of Python (*cough* 1.5.2 *cough*)
-            # that doesn't allow UserList objects to extend lists.
-            pass
-        else:
-            s = str(nl)
-            assert s == "['n3', 'n2', 'n1']", s
+        s = str(nl)
+        assert s == "['n3', 'n2', 'n1']", s
 
         r = repr(nl)
         r = re.sub('at (0[xX])?[0-9a-fA-F]+', 'at 0x', r)
diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index 9a425b6..7847a9b 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -40,8 +40,6 @@ be able to depend on any other type of "thing."
 # 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.
-#
-from __future__ import generators  ### KEEP FOR COMPATIBILITY FIXERS
 
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
@@ -1254,18 +1252,9 @@ class Node:
             lines = ["%s:\n" % preamble] + lines
             return ( ' '*11).join(lines)
 
-try:
-    [].extend(collections.UserList([]))
-except TypeError:
-    # Python 1.5.2 doesn't allow a list to be extended by list-like
-    # objects (such as UserList instances), so just punt and use
-    # real lists.
-    def NodeList(l):
-        return l
-else:
-    class NodeList(collections.UserList):
-        def __str__(self):
-            return str(list(map(str, self.data)))
+class NodeList(collections.UserList):
+    def __str__(self):
+        return str(list(map(str, self.data)))
 
 def get_children(node, parent): return node.children()
 def ignore_cycle(node, stack): pass