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Developer tools
Code, configuration and workflows. Source-linked checks to help you move forward.
Python sqlite3 foreign keys stay off with autocommit=False: initialize and verify the connection
Native Python 3.13 tests compare PRAGMA timing and setconfig, verify cascading and orphan rejection, and expose the side effect of changing autocommit.
Python sample can repeat values: without replacement refers to occurrences
Separate unique sampled positions from repeated values, compare replacement behavior, and use choices with the keyword k rather than a positional count.
Bash find loops split filenames: keep NUL records and quote each path
Compare five original filenames with a broken command-substitution loop, then use find -print0 and Bash read without losing record boundaries.
Node ES modules have no __dirname: use module metadata and file URL helpers
Compare the ESM dirname error with modern metadata and fileURLToPath, including a real path containing spaces and a hash character.
curl JSON requests: verify the body, Content-Type and actual HTTP method
Compare local curl requests for JSON media type, exact body bytes, POST versus PUT and the limits of --json without claiming an original server fix.
Git branch already checked out: find the owning worktree before forcing it
Inspect linked checkout paths and branch ownership, preserve local work, and distinguish ordinary occupancy from metadata repair or pruning cases.
VS Code Ctrl+P misses ignored files: separate ignore rules from exclude settings
Check filename Quick Open separately from text Search, review ignore-file settings and exclude globs, and verify a narrow exception or workspace change.
Git divergent branches: compare merge, rebase and fast-forward-only before pulling
Inspect a shared-base divergence, compare actual local merge and rebase graphs, and distinguish one-time pull choices from defaults and IDE behavior.
Python copy without overwriting: create the destination exclusively
Copy regular-file bytes into an exclusively created destination, verify collisions preserve old contents, and account for partial copies and metadata limits.
Git unrelated histories after an initial README: choose one starting history
Reproduce independent initial commits, compare an explicit merge with clone-and-import, and preserve local history before choosing a first-upload workflow.
Python local time to UTC: attach a named zone, then convert the instant
Convert known local calendar times with ZoneInfo, keep pytz rules separate, and test seasonal offsets, repeated times and nonexistent local times.
npm --legacy-peer-deps: installation success is not a compatible peer tree
See an offline peer-conflict fixture, separate --legacy-peer-deps from --force, and verify the lockfile, install policy and application together.
Bash variable stays zero after a piped while loop: keep the work in one shell
Reproduce a lost loop counter, compare process substitution and grouped output, and choose a direct match test when a loop is unnecessary.
Python generator after next(): loop over the remaining items safely
Verify how consuming a first item changes the remaining for loop, handle the empty case, and distinguish exhaustion from an infinite or blocking producer.
jq string output has quotes: choose raw output without deleting data
Compare JSON strings with jq raw output, preserve embedded quotes and backslashes, and verify the downstream record boundary instead of stripping characters.
Git revert -m selects a parent baseline, not a branch to remove
Read the recorded merge-parent order, compare each parent to the merge, and understand why -m 3 can reverse two branches in an octopus merge.
Python mutable defaults: why a list survives between calls
Trace definition-time default evaluation, verify repeated-call identity, and choose between fresh defaults, caller mutation and copied input.
Python CSV output has blank rows: let csv handle the newline boundary
Compare explicit text newline translation with csv-managed output, inspect raw CRLF bytes and round-trip an embedded newline without deleting valid data.