Add initial implementation of importlib. See the NOTES files for what is

planned for the package.

There are no docs yet, but they are coming once the API for the first new
function, importlib.import_module() is finalized.

1 files changed, 122 insertions, 0 deletions

diff --git a/Lib/importlib/test/source/test_source_encoding.py b/Lib/importlib/test/source/test_source_encoding.py
new file mode 100644
index 0000000..97096df
--- /dev/null
+++ b/Lib/importlib/test/source/test_source_encoding.py
@@ -0,0 +1,122 @@
+import importlib
+from .. import support
+
+import codecs
+import re
+import sys
+# Because sys.path gets essentially blanked, need to have unicodedata already
+# imported for the parser to use.
+import unicodedata
+import unittest
+
+
+CODING_RE = re.compile(r'coding[:=]\s*([-\w.]+)')
+
+
+class EncodingTest(unittest.TestCase):
+
+    """PEP 3120 makes UTF-8 the default encoding for source code
+    [default encoding].
+
+    PEP 263 specifies how that can change on a per-file basis. Either the first
+    or second line can contain the encoding line [encoding first line]
+    encoding second line]. If the file has the BOM marker it is considered UTF-8
+    implicitly [BOM]. If any encoding is specified it must be UTF-8, else it is
+    an error [BOM and utf-8][BOM conflict].
+
+    """
+
+    variable = '\u00fc'
+    character = '\u00c9'
+    source_line = "{0} = '{1}'\n".format(variable, character)
+    module_name = '_temp'
+
+    def run_test(self, source):
+        with support.create_modules(self.module_name) as mapping:
+            with open(mapping[self.module_name], 'wb')as file:
+                file.write(source)
+            loader = importlib._PyFileLoader(self.module_name,
+                                       mapping[self.module_name], False)
+            return loader.load_module(self.module_name)
+
+    def create_source(self, encoding):
+        encoding_line = "# coding={0}".format(encoding)
+        assert CODING_RE.search(encoding_line)
+        source_lines = [encoding_line.encode('utf-8')]
+        source_lines.append(self.source_line.encode(encoding))
+        return b'\n'.join(source_lines)
+
+    def test_non_obvious_encoding(self):
+        # Make sure that an encoding that has never been a standard one for
+        # Python works.
+        encoding_line = "# coding=koi8-r"
+        assert CODING_RE.search(encoding_line)
+        source = "{0}\na=42\n".format(encoding_line).encode("koi8-r")
+        self.run_test(source)
+
+    # [default encoding]
+    def test_default_encoding(self):
+        self.run_test(self.source_line.encode('utf-8'))
+
+    # [encoding first line]
+    def test_encoding_on_first_line(self):
+        encoding = 'Latin-1'
+        source = self.create_source(encoding)
+        self.run_test(source)
+
+    # [encoding second line]
+    def test_encoding_on_second_line(self):
+        source = b"#/usr/bin/python\n" + self.create_source('Latin-1')
+        self.run_test(source)
+
+    # [BOM]
+    def test_bom(self):
+        self.run_test(codecs.BOM_UTF8 + self.source_line.encode('utf-8'))
+
+    # [BOM and utf-8]
+    def test_bom_and_utf_8(self):
+        source = codecs.BOM_UTF8 + self.create_source('utf-8')
+        self.run_test(source)
+
+    # [BOM conflict]
+    def test_bom_conflict(self):
+        source = codecs.BOM_UTF8 + self.create_source('latin-1')
+        self.assertRaises(SyntaxError, self.run_test, source)
+
+
+class LineEndingTest(unittest.TestCase):
+
+    r"""Source written with the three types of line endings (\n, \r\n, \r)
+    need to be readable [cr][crlf][lf]."""
+
+    def run_test(self, line_ending):
+        module_name = '_temp'
+        source_lines = [b"a = 42", b"b = -13", b'']
+        source = line_ending.join(source_lines)
+        with support.create_modules(module_name) as mapping:
+            with open(mapping[module_name], 'wb') as file:
+                file.write(source)
+            loader = importlib._PyFileLoader(module_name, mapping[module_name],
+                                                False)
+            return loader.load_module(module_name)
+
+    # [cr]
+    def test_cr(self):
+        self.run_test(b'\r')
+
+    # [crlf]
+    def test_crlf(self):
+        self.run_test(b'\r\n')
+
+    # [lf]
+    def test_lf(self):
+        self.run_test(b'\n')
+
+
+def test_main():
+    from test.support import run_unittest
+    run_unittest(EncodingTest, LineEndingTest)
+
+
+if __name__ == '__main__':
+    test_main()