bpo-32831: IDLE: Add docstrings and tests for codecontext (GH-5638)

1 files changed, 347 insertions, 0 deletions

diff --git a/Lib/idlelib/idle_test/test_codecontext.py b/Lib/idlelib/idle_test/test_codecontext.py
new file mode 100644
index 0000000..448094e
--- /dev/null
+++ b/Lib/idlelib/idle_test/test_codecontext.py
@@ -0,0 +1,347 @@
+"""Test idlelib.codecontext.
+
+Coverage: 100%
+"""
+
+import re
+
+import unittest
+from unittest import mock
+from test.support import requires
+from tkinter import Tk, Frame, Text, TclError
+
+import idlelib.codecontext as codecontext
+from idlelib import config
+
+
+usercfg = codecontext.idleConf.userCfg
+testcfg = {
+    'main': config.IdleUserConfParser(''),
+    'highlight': config.IdleUserConfParser(''),
+    'keys': config.IdleUserConfParser(''),
+    'extensions': config.IdleUserConfParser(''),
+}
+code_sample = """\
+
+class C1():
+    # Class comment.
+    def __init__(self, a, b):
+        self.a = a
+        self.b = b
+    def compare(self):
+        if a > b:
+            return a
+        elif a < b:
+            return b
+        else:
+            return None
+"""
+
+
+class DummyEditwin:
+    def __init__(self, root, frame, text):
+        self.root = root
+        self.top = root
+        self.text_frame = frame
+        self.text = text
+
+
+class CodeContextTest(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        requires('gui')
+        root = cls.root = Tk()
+        root.withdraw()
+        frame = cls.frame = Frame(root)
+        text = cls.text = Text(frame)
+        text.insert('1.0', code_sample)
+        # Need to pack for creation of code context label widget.
+        frame.pack(side='left', fill='both', expand=1)
+        text.pack(side='top', fill='both', expand=1)
+        cls.editor = DummyEditwin(root, frame, text)
+        codecontext.idleConf.userCfg = testcfg
+
+    @classmethod
+    def tearDownClass(cls):
+        codecontext.idleConf.userCfg = usercfg
+        cls.editor.text.delete('1.0', 'end')
+        del cls.editor, cls.frame, cls.text
+        cls.root.update_idletasks()
+        cls.root.destroy()
+        del cls.root
+
+    def setUp(self):
+        self.cc = codecontext.CodeContext(self.editor)
+
+    def tearDown(self):
+        if self.cc.label:
+            self.cc.label.destroy()
+        # Explicitly call __del__ to remove scheduled scripts.
+        self.cc.__del__()
+        del self.cc.label, self.cc
+
+    def test_init(self):
+        eq = self.assertEqual
+        ed = self.editor
+        cc = self.cc
+
+        eq(cc.editwin, ed)
+        eq(cc.text, ed.text)
+        eq(cc.textfont, ed.text['font'])
+        self.assertIsNone(cc.label)
+        eq(cc.info, [(0, -1, '', False)])
+        eq(cc.topvisible, 1)
+        eq(self.root.tk.call('after', 'info', self.cc.t1)[1], 'timer')
+        eq(self.root.tk.call('after', 'info', self.cc.t2)[1], 'timer')
+
+    def test_del(self):
+        self.root.tk.call('after', 'info', self.cc.t1)
+        self.root.tk.call('after', 'info', self.cc.t2)
+        self.cc.__del__()
+        with self.assertRaises(TclError) as msg:
+            self.root.tk.call('after', 'info', self.cc.t1)
+            self.assertIn("doesn't exist", msg)
+        with self.assertRaises(TclError) as msg:
+            self.root.tk.call('after', 'info', self.cc.t2)
+            self.assertIn("doesn't exist", msg)
+        # For coverage on the except.  Have to delete because the
+        # above Tcl error is caught by after_cancel.
+        del self.cc.t1, self.cc.t2
+        self.cc.__del__()
+
+    def test_reload(self):
+        codecontext.CodeContext.reload()
+        self.assertEqual(self.cc.context_depth, 3)
+
+    def test_toggle_code_context_event(self):
+        eq = self.assertEqual
+        cc = self.cc
+        toggle = cc.toggle_code_context_event
+
+        # Make sure code context is off.
+        if cc.label:
+            toggle()
+
+        # Toggle on.
+        eq(toggle(), 'break')
+        self.assertIsNotNone(cc.label)
+        eq(cc.label['font'], cc.textfont)
+        eq(cc.label['fg'], cc.fgcolor)
+        eq(cc.label['bg'], cc.bgcolor)
+        eq(cc.label['text'], '\n' * 2)
+
+        # Toggle off.
+        eq(toggle(), 'break')
+        self.assertIsNone(cc.label)
+
+    def test_get_line_info(self):
+        eq = self.assertEqual
+        gli = self.cc.get_line_info
+
+        # Line 1 is not a BLOCKOPENER.
+        eq(gli(1), (codecontext.INFINITY, '', False))
+        # Line 2 is a BLOCKOPENER without an indent.
+        eq(gli(2), (0, 'class C1():', 'class'))
+        # Line 3 is not a BLOCKOPENER and does not return the indent level.
+        eq(gli(3), (codecontext.INFINITY, '    # Class comment.', False))
+        # Line 4 is a BLOCKOPENER and is indented.
+        eq(gli(4), (4, '    def __init__(self, a, b):', 'def'))
+        # Line 8 is a different BLOCKOPENER and is indented.
+        eq(gli(8), (8, '        if a > b:', 'if'))
+
+    def test_get_context(self):
+        eq = self.assertEqual
+        gc = self.cc.get_context
+
+        # stopline must be greater than 0.
+        with self.assertRaises(AssertionError):
+            gc(1, stopline=0)
+
+        eq(gc(3), ([(2, 0, 'class C1():', 'class')], 0))
+
+        # Don't return comment.
+        eq(gc(4), ([(2, 0, 'class C1():', 'class')], 0))
+
+        # Two indentation levels and no comment.
+        eq(gc(5), ([(2, 0, 'class C1():', 'class'),
+                    (4, 4, '    def __init__(self, a, b):', 'def')], 0))
+
+        # Only one 'def' is returned, not both at the same indent level.
+        eq(gc(10), ([(2, 0, 'class C1():', 'class'),
+                     (7, 4, '    def compare(self):', 'def'),
+                     (8, 8, '        if a > b:', 'if')], 0))
+
+        # With 'elif', also show the 'if' even though it's at the same level.
+        eq(gc(11), ([(2, 0, 'class C1():', 'class'),
+                     (7, 4, '    def compare(self):', 'def'),
+                     (8, 8, '        if a > b:', 'if'),
+                     (10, 8, '        elif a < b:', 'elif')], 0))
+
+        # Set stop_line to not go back to first line in source code.
+        # Return includes stop_line.
+        eq(gc(11, stopline=2), ([(2, 0, 'class C1():', 'class'),
+                                 (7, 4, '    def compare(self):', 'def'),
+                                 (8, 8, '        if a > b:', 'if'),
+                                 (10, 8, '        elif a < b:', 'elif')], 0))
+        eq(gc(11, stopline=3), ([(7, 4, '    def compare(self):', 'def'),
+                                 (8, 8, '        if a > b:', 'if'),
+                                 (10, 8, '        elif a < b:', 'elif')], 4))
+        eq(gc(11, stopline=8), ([(8, 8, '        if a > b:', 'if'),
+                                 (10, 8, '        elif a < b:', 'elif')], 8))
+
+        # Set stop_indent to test indent level to stop at.
+        eq(gc(11, stopindent=4), ([(7, 4, '    def compare(self):', 'def'),
+                                   (8, 8, '        if a > b:', 'if'),
+                                   (10, 8, '        elif a < b:', 'elif')], 4))
+        # Check that the 'if' is included.
+        eq(gc(11, stopindent=8), ([(8, 8, '        if a > b:', 'if'),
+                                   (10, 8, '        elif a < b:', 'elif')], 8))
+
+    def test_update_code_context(self):
+        eq = self.assertEqual
+        cc = self.cc
+        # Ensure code context is active.
+        if not cc.label:
+            cc.toggle_code_context_event()
+
+        # Invoke update_code_context without scrolling - nothing happens.
+        self.assertIsNone(cc.update_code_context())
+        eq(cc.info, [(0, -1, '', False)])
+        eq(cc.topvisible, 1)
+
+        # Scroll down to line 2.
+        cc.text.yview(2)
+        cc.update_code_context()
+        eq(cc.info, [(0, -1, '', False), (2, 0, 'class C1():', 'class')])
+        eq(cc.topvisible, 3)
+        # context_depth is 3 so it pads with blank lines.
+        eq(cc.label['text'], '\n'
+                             '\n'
+                             'class C1():')
+
+        # Scroll down to line 3.  Since it's a comment, nothing changes.
+        cc.text.yview(3)
+        cc.update_code_context()
+        eq(cc.info, [(0, -1, '', False), (2, 0, 'class C1():', 'class')])
+        eq(cc.topvisible, 4)
+        eq(cc.label['text'], '\n'
+                             '\n'
+                             'class C1():')
+
+        # Scroll down to line 4.
+        cc.text.yview(4)
+        cc.update_code_context()
+        eq(cc.info, [(0, -1, '', False),
+                     (2, 0, 'class C1():', 'class'),
+                     (4, 4, '    def __init__(self, a, b):', 'def')])
+        eq(cc.topvisible, 5)
+        eq(cc.label['text'], '\n'
+                             'class C1():\n'
+                             '    def __init__(self, a, b):')
+
+        # Scroll down to line 11.  Last 'def' is removed.
+        cc.text.yview(11)
+        cc.update_code_context()
+        eq(cc.info, [(0, -1, '', False),
+                     (2, 0, 'class C1():', 'class'),
+                     (7, 4, '    def compare(self):', 'def'),
+                     (8, 8, '        if a > b:', 'if'),
+                     (10, 8, '        elif a < b:', 'elif')])
+        eq(cc.topvisible, 12)
+        eq(cc.label['text'], '    def compare(self):\n'
+                             '        if a > b:\n'
+                             '        elif a < b:')
+
+        # No scroll.  No update, even though context_depth changed.
+        cc.update_code_context()
+        cc.context_depth = 1
+        eq(cc.info, [(0, -1, '', False),
+                     (2, 0, 'class C1():', 'class'),
+                     (7, 4, '    def compare(self):', 'def'),
+                     (8, 8, '        if a > b:', 'if'),
+                     (10, 8, '        elif a < b:', 'elif')])
+        eq(cc.topvisible, 12)
+        eq(cc.label['text'], '    def compare(self):\n'
+                             '        if a > b:\n'
+                             '        elif a < b:')
+
+        # Scroll up.
+        cc.text.yview(5)
+        cc.update_code_context()
+        eq(cc.info, [(0, -1, '', False),
+                     (2, 0, 'class C1():', 'class'),
+                     (4, 4, '    def __init__(self, a, b):', 'def')])
+        eq(cc.topvisible, 6)
+        # context_depth is 1.
+        eq(cc.label['text'], '    def __init__(self, a, b):')
+
+    @mock.patch.object(codecontext.CodeContext, 'update_code_context')
+    def test_timer_event(self, mock_update):
+        # Ensure code context is not active.
+        if self.cc.label:
+            self.cc.toggle_code_context_event()
+        self.cc.timer_event()
+        mock_update.assert_not_called()
+
+        # Activate code context.
+        self.cc.toggle_code_context_event()
+        self.cc.timer_event()
+        mock_update.assert_called()
+
+    def test_font_timer_event(self):
+        eq = self.assertEqual
+        cc = self.cc
+        save_font = cc.text['font']
+        test_font = 'FakeFont'
+
+        # Ensure code context is not active.
+        if cc.label:
+            cc.toggle_code_context_event()
+
+        # Nothing updates on inactive code context.
+        cc.text['font'] = test_font
+        cc.font_timer_event()
+        eq(cc.textfont, save_font)
+
+        # Activate code context, but no change to font.
+        cc.toggle_code_context_event()
+        cc.text['font'] = save_font
+        cc.font_timer_event()
+        eq(cc.textfont, save_font)
+        eq(cc.label['font'], save_font)
+
+        # Active code context, change font.
+        cc.text['font'] = test_font
+        cc.font_timer_event()
+        eq(cc.textfont, test_font)
+        eq(cc.label['font'], test_font)
+
+        cc.text['font'] = save_font
+        cc.font_timer_event()
+
+
+class HelperFunctionText(unittest.TestCase):
+
+    def test_getspacesfirstword(self):
+        get = codecontext.getspacesfirstword
+        test_lines = (
+            ('    first word', ('    ', 'first')),
+            ('\tfirst word', ('\t', 'first')),
+            ('  \u19D4\u19D2: ', ('  ', '\u19D4\u19D2')),
+            ('no spaces', ('', 'no')),
+            ('', ('', '')),
+            ('# TEST COMMENT', ('', '')),
+            ('    (continuation)', ('    ', ''))
+            )
+        for line, expected_output in test_lines:
+            self.assertEqual(get(line), expected_output)
+
+        # Send the pattern in the call.
+        self.assertEqual(get('    (continuation)',
+                             c=re.compile(r'^(\s*)([^\s]*)')),
+                         ('    ', '(continuation)'))
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)