Add Start The Debugger When A Test Errors as a Python TIL

README.md

@@ -10,7 +10,7 @@ working across different projects via [VisualMode](https://www.visualmode.dev/).
 
 For a steady stream of TILs, [sign up for my newsletter](https://visualmode.kit.com/newsletter).
 
-_1764 TILs and counting..._
+_1766 TILs and counting..._
 
 See some of the other learning resources I work on:
 
@@ -1060,6 +1060,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Look Inside Pytest tmp_path](python/look-inside-pytest-tmp-path.md)
 - [Override The Boolean Context Of A Class](python/override-the-boolean-context-of-a-class.md)
 - [Parse Relative Time To datetime Object](python/parse-relative-time-to-datetime-object.md)
+- [Start The Debugger When A Test Errors](python/start-the-debugger-when-a-test-errors.md)
 - [Store And Access Immutable Data In A Tuple](python/store-and-access-immutable-data-in-a-tuple.md)
 - [Test A Function With Pytest](python/test-a-function-with-pytest.md)
 - [Use pipx To Install End User Apps](python/use-pipx-to-install-end-user-apps.md)
@@ -1578,6 +1579,7 @@ If you've learned something here, support my efforts writing daily TILs by
 
 ### Taskfile
 
+- [Add Default Task To List All Tasks](taskfile/add-default-task-to-list-all-tasks.md)
 - [Create Interactive Picker For Set Of Subtasks](taskfile/create-interactive-picker-for-set-of-subtasks.md)
 - [Run A Task If It Meets Criteria](taskfile/run-a-task-if-it-meets-criteria.md)
 

python/start-the-debugger-when-a-test-errors.md

@@ -0,0 +1,27 @@
+# Start The Debugger When A Test Errors
+
+While working on [some
+tests](https://github.com/jbranchaud/build-an-llm-from-scratch/blob/main/tests/chapter_02/test_bpe_tokenizer.py)
+for my Byte Pair Encoding tokenizer, I was running into an unexpected test
+failure. To better understand what was going on, I needed to inspect the state
+of the program around the time the code raised an exception.
+
+Instead of needing to manually set a breakpoint at the correct spot to begin
+debugging, I can run the test with the Pytest-supported `--pdb` flag. That's
+short for _python debugger_.
+
+> Start the interactive Python debugger on errors or KeyboardInterrupt
+
+What this does during a test run is opens you up to the interactive Python
+debugger at the exact moment an exception is raised. This gives you the ability
+to inspect values of the program state at that point in execution which could
+help inform the needed fix.
+
+```bash
+uv run pytest -vv --pdb -k "test_train_bpe"
+```
+
+There I am running a specific test that matches against `-k "test_train_bpe"`
+and the python debugger will start up if there is an error.
+
+See `uv run pytest --help` for more details.

taskfile/add-default-task-to-list-all-tasks.md

@@ -0,0 +1,52 @@
+# Add Default Task To List All Tasks
+
+One thing I like about [`just`](https://github.com/casey/just) is that if you
+run `just` by itself, the default behavior is to list out all the commands it
+can run.
+
+[Taskfile](https://github.com/go-task/task) technically does this as well, but
+with a warning at the end:
+
+```
+❯ task
+task: Available tasks for this project:
+* notes:              Interactive picker for notes tasks
+* notes:diff:         Show uncommitted changes in notes
+* notes:edit:         All-in-one edit, commit, and push notes
+* notes:log:          Show recent commit history for notes
+* notes:open:         Opens NOTES.md (syncs latest changes first) in default editor
+* notes:push:         Commit and push changes to notes submodule
+* notes:status:       Check status of notes submodule
+* notes:sync:         Sync latest changes from the notes submodule
+task: Task "default" does not exist
+```
+
+I prefer to tidy this up a little by adding `task --list` as the _default_ in my
+`Taskfile.yml`.
+
+```yml
+  default:
+    desc: Show available commands
+    cmds:
+      - task --list
+```
+
+Now when I run `task` with no arguments, I get this minutely nicer version:
+
+```
+❯ task
+Alias tip: t
+task: [default] task --list
+task: Available tasks for this project:
+* default:            Show available commands
+* notes:              Interactive picker for notes tasks
+* notes:diff:         Show uncommitted changes in notes
+* notes:edit:         All-in-one edit, commit, and push notes
+* notes:log:          Show recent commit history for notes
+* notes:open:         Opens NOTES.md (syncs latest changes first) in default editor
+* notes:push:         Commit and push changes to notes submodule
+* notes:status:       Check status of notes submodule
+* notes:sync:         Sync latest changes from the notes submodule
+```
+
+Notice there is no `task: Task "default" does not exist` warning at the end.