2.2 to 2.3 An empty text, and case

Build it yourself. Read the tutorial is the other way to read this part.

If you start at this part, make your clone as Get the project says, and then run this command. It puts in your clone the files that this part starts from. A file that the project deleted before this part stays, so delete it if git check lists it:

git rm -rq --cached --ignore-unmatch -- :/ && git restore --source 6a4b1a0e5003 --staged --worktree -- :/

just setup

The code before this part. The code after it.

2.2 A test of an empty text

An empty file is a text with no words. count must give an empty dictionary for it, and not fail. A test in a file of its own, tests/test_empty.py, says so, and keeps it true after later changes.

Apply the patch to tests/test_empty.py, from the top of the project:

curl -fsSL https://github.com/rahuldave/tally/commit/4f9bfa3d9c08307287e81a631039894490a3e590.diff | git apply --include=tests/test_empty.py

The patch makes the file tests/test_empty.py, with the class Empty and its test.

uv run python -m unittest discover -s tests -q

The new test passes at once, because split() finds no words in an empty text. test_case still fails.

Check your files against this move. The command prints nothing when they match, and otherwise shows what differs:

git check 4f9bfa3d9c08

If you are stuck, this command puts the files of this move in place of yours. A file that you made yourself stays:

git restore --source 6a4b1a0e5003 --staged -- :/ && git restore --source 4f9bfa3d9c08 --staged --worktree -- :/

What changed

tests/test_empty.py: an empty text counts nothing. New, 8 lines. The file.
- look at self.assertEqual(count(""), {})

The patch to tests/test_empty.py

@@ -0,0 +1,8 @@
+import unittest
+
+from tally import count
+
+
+class Empty(unittest.TestCase):
+    def test_empty(self):
+        self.assertEqual(count(""), {})

This change on GitHub. The code after it.

2.3 Case does not matter

test_case fails, because count counts A and a as two words. When count puts the text in lower case before it splits it, every word is counted in lower case. One word in the loop of count, lower(), does it.

Apply the patch to src/tally/__init__.py, from the top of the project:

curl -fsSL https://github.com/rahuldave/tally/commit/bfcbe07463b5c6f3c0764e4ac19a054cb0acee20.diff | git apply --include=src/tally/__init__.py

In count, the patch puts text.lower().split() in place of text.split().

uv run python -m unittest discover -s tests -q
echo "The the" | uv run tally

All three tests pass, and the command prints 2 the for "The the".

Check your files against this move. The command prints nothing when they match, and otherwise shows what differs:

git check bfcbe07463b5

If you are stuck, this command puts the files of this move in place of yours. A file that you made yourself stays:

git restore --source 4f9bfa3d9c08 --staged -- :/ && git restore --source bfcbe07463b5 --staged --worktree -- :/

What changed

src/tally/__init__.py: one word, lower(), answers the failing test. 1 line added, 1 removed. The file.
- look at for word in text.lower().split():

The patch to src/tally/__init__.py

@@ -5,7 +5,7 @@ import sys
 
 def count(text):
     counts = {}
-    for word in text.split():
+    for word in text.lower().split():
         counts[word] = counts.get(word, 0) + 1
     return counts

This change on GitHub. The code after it.