bpo-36952: Remove the bufsize parameter in fileinput.input(). (GH-13400)

This parameter is marked as deprecated since 3.6 and for removal in 3.8.
It already had no effects.

2 files changed, 23 insertions, 40 deletions

diff --git a/Lib/fileinput.py b/Lib/fileinput.py
index 0764aa5..d868e74 100644
--- a/Lib/fileinput.py
+++ b/Lib/fileinput.py
@@ -80,8 +80,7 @@ __all__ = ["input", "close", "nextfile", "filename", "lineno", "filelineno",
 
 _state = None
 
-def input(files=None, inplace=False, backup="", bufsize=0,
-          mode="r", openhook=None):
+def input(files=None, inplace=False, backup="", *, mode="r", openhook=None):
     """Return an instance of the FileInput class, which can be iterated.
 
     The parameters are passed to the constructor of the FileInput class.
@@ -91,7 +90,7 @@ def input(files=None, inplace=False, backup="", bufsize=0,
     global _state
     if _state and _state._file:
         raise RuntimeError("input() already active")
-    _state = FileInput(files, inplace, backup, bufsize, mode, openhook)
+    _state = FileInput(files, inplace, backup, mode=mode, openhook=openhook)
     return _state
 
 def close():
@@ -173,7 +172,7 @@ def isstdin():
     return _state.isstdin()
 
 class FileInput:
-    """FileInput([files[, inplace[, backup[, bufsize, [, mode[, openhook]]]]]])
+    """FileInput([files[, inplace[, backup]]], *, mode=None, openhook=None)
 
     Class FileInput is the implementation of the module; its methods
     filename(), lineno(), fileline(), isfirstline(), isstdin(), fileno(),
@@ -185,7 +184,7 @@ class FileInput:
     sequential order; random access and readline() cannot be mixed.
     """
 
-    def __init__(self, files=None, inplace=False, backup="", bufsize=0,
+    def __init__(self, files=None, inplace=False, backup="", *,
                  mode="r", openhook=None):
         if isinstance(files, str):
             files = (files,)
@@ -201,10 +200,6 @@ class FileInput:
         self._files = files
         self._inplace = inplace
         self._backup = backup
-        if bufsize:
-            import warnings
-            warnings.warn('bufsize is deprecated and ignored',
-                          DeprecationWarning, stacklevel=2)
         self._savestdout = None
         self._output = None
         self._filename = None
diff --git a/Lib/test/test_fileinput.py b/Lib/test/test_fileinput.py
index 8b7577b..014f19e 100644
--- a/Lib/test/test_fileinput.py
+++ b/Lib/test/test_fileinput.py
@@ -82,25 +82,17 @@ class LineReader:
 
 class BufferSizesTests(BaseTests, unittest.TestCase):
     def test_buffer_sizes(self):
-        # First, run the tests with default and teeny buffer size.
-        for round, bs in (0, 0), (1, 30):
-            t1 = self.writeTmp(''.join("Line %s of file 1\n" % (i+1) for i in range(15)))
-            t2 = self.writeTmp(''.join("Line %s of file 2\n" % (i+1) for i in range(10)))
-            t3 = self.writeTmp(''.join("Line %s of file 3\n" % (i+1) for i in range(5)))
-            t4 = self.writeTmp(''.join("Line %s of file 4\n" % (i+1) for i in range(1)))
-            if bs:
-                with self.assertWarns(DeprecationWarning):
-                    self.buffer_size_test(t1, t2, t3, t4, bs, round)
-            else:
-                self.buffer_size_test(t1, t2, t3, t4, bs, round)
-
-    def buffer_size_test(self, t1, t2, t3, t4, bs=0, round=0):
+
+        t1 = self.writeTmp(''.join("Line %s of file 1\n" % (i+1) for i in range(15)))
+        t2 = self.writeTmp(''.join("Line %s of file 2\n" % (i+1) for i in range(10)))
+        t3 = self.writeTmp(''.join("Line %s of file 3\n" % (i+1) for i in range(5)))
+        t4 = self.writeTmp(''.join("Line %s of file 4\n" % (i+1) for i in range(1)))
+
         pat = re.compile(r'LINE (\d+) OF FILE (\d+)')
 
-        start = 1 + round*6
         if verbose:
-            print('%s. Simple iteration (bs=%s)' % (start+0, bs))
-        fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
+            print('1. Simple iteration')
+        fi = FileInput(files=(t1, t2, t3, t4))
         lines = list(fi)
         fi.close()
         self.assertEqual(len(lines), 31)
@@ -110,8 +102,8 @@ class BufferSizesTests(BaseTests, unittest.TestCase):
         self.assertEqual(fi.filename(), t4)
 
         if verbose:
-            print('%s. Status variables (bs=%s)' % (start+1, bs))
-        fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
+            print('2. Status variables')
+        fi = FileInput(files=(t1, t2, t3, t4))
         s = "x"
         while s and s != 'Line 6 of file 2\n':
             s = fi.readline()
@@ -122,15 +114,15 @@ class BufferSizesTests(BaseTests, unittest.TestCase):
         self.assertFalse(fi.isstdin())
 
         if verbose:
-            print('%s. Nextfile (bs=%s)' % (start+2, bs))
+            print('3. Nextfile')
         fi.nextfile()
         self.assertEqual(fi.readline(), 'Line 1 of file 3\n')
         self.assertEqual(fi.lineno(), 22)
         fi.close()
 
         if verbose:
-            print('%s. Stdin (bs=%s)' % (start+3, bs))
-        fi = FileInput(files=(t1, t2, t3, t4, '-'), bufsize=bs)
+            print('4. Stdin')
+        fi = FileInput(files=(t1, t2, t3, t4, '-'))
         savestdin = sys.stdin
         try:
             sys.stdin = StringIO("Line 1 of stdin\nLine 2 of stdin\n")
@@ -143,8 +135,8 @@ class BufferSizesTests(BaseTests, unittest.TestCase):
             sys.stdin = savestdin
 
         if verbose:
-            print('%s. Boundary conditions (bs=%s)' % (start+4, bs))
-        fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
+            print('5. Boundary conditions')
+        fi = FileInput(files=(t1, t2, t3, t4))
         self.assertEqual(fi.lineno(), 0)
         self.assertEqual(fi.filename(), None)
         fi.nextfile()
@@ -152,10 +144,10 @@ class BufferSizesTests(BaseTests, unittest.TestCase):
         self.assertEqual(fi.filename(), None)
 
         if verbose:
-            print('%s. Inplace (bs=%s)' % (start+5, bs))
+            print('6. Inplace')
         savestdout = sys.stdout
         try:
-            fi = FileInput(files=(t1, t2, t3, t4), inplace=1, bufsize=bs)
+            fi = FileInput(files=(t1, t2, t3, t4), inplace=1)
             for line in fi:
                 line = line[:-1].upper()
                 print(line)
@@ -163,7 +155,7 @@ class BufferSizesTests(BaseTests, unittest.TestCase):
         finally:
             sys.stdout = savestdout
 
-        fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
+        fi = FileInput(files=(t1, t2, t3, t4))
         for line in fi:
             self.assertEqual(line[-1], '\n')
             m = pat.match(line[:-1])
@@ -533,12 +525,11 @@ class FileInputTests(BaseTests, unittest.TestCase):
 class MockFileInput:
     """A class that mocks out fileinput.FileInput for use during unit tests"""
 
-    def __init__(self, files=None, inplace=False, backup="", bufsize=0,
+    def __init__(self, files=None, inplace=False, backup="", *,
                  mode="r", openhook=None):
         self.files = files
         self.inplace = inplace
         self.backup = backup
-        self.bufsize = bufsize
         self.mode = mode
         self.openhook = openhook
         self._file = None
@@ -641,13 +632,11 @@ class Test_fileinput_input(BaseFileInputGlobalMethodsTest):
         files = object()
         inplace = object()
         backup = object()
-        bufsize = object()
         mode = object()
         openhook = object()
 
         # call fileinput.input() with different values for each argument
         result = fileinput.input(files=files, inplace=inplace, backup=backup,
-                                 bufsize=bufsize,
             mode=mode, openhook=openhook)
 
         # ensure fileinput._state was set to the returned object
@@ -658,7 +647,6 @@ class Test_fileinput_input(BaseFileInputGlobalMethodsTest):
         self.assertIs(files, result.files, "files")
         self.assertIs(inplace, result.inplace, "inplace")
         self.assertIs(backup, result.backup, "backup")
-        self.assertIs(bufsize, result.bufsize, "bufsize")
         self.assertIs(mode, result.mode, "mode")
         self.assertIs(openhook, result.openhook, "openhook")