rna transcription exercise

python/rna-transcription/.exercism/metadata.json

@@ -0,0 +1 @@
+{"track":"python","exercise":"rna-transcription","id":"3fc8fca40565475dbeb36f5e8048281f","url":"https://exercism.io/my/solutions/3fc8fca40565475dbeb36f5e8048281f","handle":"Xevion","is_requester":true,"auto_approve":false}

python/rna-transcription/README.md

@@ -0,0 +1,68 @@
+# RNA Transcription
+
+Given a DNA strand, return its RNA complement (per RNA transcription).
+
+Both DNA and RNA strands are a sequence of nucleotides.
+
+The four nucleotides found in DNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and thymine (**T**).
+
+The four nucleotides found in RNA are adenine (**A**), cytosine (**C**),
+guanine (**G**) and uracil (**U**).
+
+Given a DNA strand, its transcribed RNA strand is formed by replacing
+each nucleotide with its complement:
+
+* `G` -> `C`
+* `C` -> `G`
+* `T` -> `A`
+* `A` -> `U`
+
+## Exception messages
+
+Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to
+indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not
+every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include
+a message.
+
+To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
+`raise Exception`, you should write:
+
+```python
+raise Exception("Meaningful message indicating the source of the error")
+```
+
+## Running the tests
+
+To run the tests, run the appropriate command below ([why they are different](https://github.com/pytest-dev/pytest/issues/1629#issue-161422224)):
+
+- Python 2.7: `py.test rna_transcription_test.py`
+- Python 3.4+: `pytest rna_transcription_test.py`
+
+Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version):
+`python -m pytest rna_transcription_test.py`
+
+### Common `pytest` options
+
+- `-v` : enable verbose output
+- `-x` : stop running tests on first failure
+- `--ff` : run failures from previous test before running other test cases
+
+For other options, see `python -m pytest -h`
+
+## Submitting Exercises
+
+Note that, when trying to submit an exercise, make sure the solution is in the `$EXERCISM_WORKSPACE/python/rna-transcription` directory.
+
+You can find your Exercism workspace by running `exercism debug` and looking for the line that starts with `Workspace`.
+
+For more detailed information about running tests, code style and linting,
+please see [Running the Tests](http://exercism.io/tracks/python/tests).
+
+## Source
+
+Hyperphysics [http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html](http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html)
+
+## Submitting Incomplete Solutions
+
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.

python/rna-transcription/rna_transcription.py

@@ -0,0 +1,3 @@
+transition = {'G':'C', 'C':'G', 'T':'A', 'A':'U'}
+def to_rna(dna_strand):
+    return ''.join(transition[char] for char in dna_strand)

python/rna-transcription/rna_transcription_test.py

@@ -0,0 +1,30 @@
+import unittest
+
+from rna_transcription import to_rna
+
+
+# Tests adapted from `problem-specifications//canonical-data.json` @ v1.3.0
+
+class RnaTranscriptionTest(unittest.TestCase):
+
+    def test_empty_rna_sequence(self):
+        self.assertEqual(to_rna(""), "")
+
+    def test_transcribes_cytosine_to_guanine(self):
+        self.assertEqual(to_rna('C'), 'G')
+
+    def test_transcribes_guanine_to_cytosine(self):
+        self.assertEqual(to_rna('G'), 'C')
+
+    def test_transcribes_thymine_to_adenine(self):
+        self.assertEqual(to_rna('T'), 'A')
+
+    def test_transcribes_adenine_to_uracil(self):
+        self.assertEqual(to_rna('A'), 'U')
+
+    def test_transcribes_all_occurrences(self):
+        self.assertEqual(to_rna('ACGTGGTCTTAA'), 'UGCACCAGAAUU')
+
+
+if __name__ == '__main__':
+    unittest.main()