Fix deleteLine to behave correctly on edge cases

deleteLine used to remove the previous line end, rather than the line end
for the current line, which was really stupid.

Author: bruderstein

PythonScript/python_tests/tests/ScintillaWrapperTestCase.py

@@ -971,4 +971,35 @@ def test_getCharacterPointer(self):
         text = editor.getCharacterPointer()
         self.assertEqual(text, 'Hello world char pointer')
 
+    def test_deleteLine_with_contents(self):
+        editor.write('Line 1\r\nLine 2\r\nLine 3\r\n')
+        editor.deleteLine(1)
+        text = editor.getText();
+        self.assertEqual(text, 'Line 1\r\nLine 3\r\n')
+
+    def test_deleteLine_middle_no_contents(self):
+        editor.write('Line 1\r\n\r\nLine 3\r\n')
+        editor.deleteLine(1)
+        text = editor.getText();
+        self.assertEqual(text, 'Line 1\r\nLine 3\r\n')
+        
+    def test_deleteLine_end_no_contents(self):
+        editor.write('Line 1\r\nLine 2\r\n\r\n')
+        editor.deleteLine(2)
+        text = editor.getText();
+        self.assertEqual(text, 'Line 1\r\nLine 2\r\n')
+
+    def test_deleteLine_end_no_eol(self):
+        editor.write('Line 1\r\nLine 2\r\nLine 3')
+        editor.deleteLine(2)
+        text = editor.getText();
+        self.assertEqual(text, 'Line 1\r\nLine 2\r\n')
+
+    def test_deleteLine_start_no_contents(self):
+        editor.write('\r\nLine 2\r\nLine 3\r\n')
+        editor.deleteLine(0)
+        text = editor.getText();
+        self.assertEqual(text, 'Line 2\r\nLine 3\r\n')
+        
+
 suite = unittest.TestLoader().loadTestsFromTestCase(ScintillaWrapperTestCase)

PythonScript/src/ScintillaWrapper.cpp

@@ -506,13 +506,18 @@ void ScintillaWrapper::forEachLine(PyObject* function)
 
 void ScintillaWrapper::deleteLine(int lineNumber)
 {
-	int start = 0;
+	int start = PositionFromLine(lineNumber);
 	int lineCount = GetLineCount();
-	if (0 != lineNumber && lineCount != 1)
+    int end;
+	if (lineCount > lineNumber)
+	{
+		end = PositionFromLine(lineNumber + 1);
+	}
+	else
 	{
-		start = GetLineEndPosition(lineNumber - 1);
+		end = GetLineEndPosition(lineNumber);
 	}
-	int end = GetLineEndPosition(lineNumber);
+
 	setTarget(start, end);
 	this->ReplaceTarget(boost::python::str(""));
 }