The guidebook / 181 guides
Developer tools
Code, configuration and workflows. Source-linked checks to help you move forward.
An empty folder disappears from a Git clone: track a deliberate placeholder
Compare normal git add on an empty folder with a tracked placeholder, verify a fresh clone and separate application emptiness from directory layout.
json.load reports Extra data after repeated dumps: choose one document boundary
Reproduce concatenated JSON roots, compare one array with one-record-per-line output and reject line parsing for pretty-printed multi-line documents.
curl saves the redirect response: follow Location and verify the final payload
Compare a redirect body with the final GET payload, inspect effective URL and redirect count, and separate HTTP redirects from login pages and scripts.
argparse reads False as true: choose a flag or an explicit text converter
Reproduce type=bool with False and empty strings, compare optional boolean flags and validate a text converter with rejected invalid input.
Git ignores a file you did not exclude: find the exact rule source
Read the matching source, line and pattern for an unexpectedly ignored path, distinguish tracked files and verify a narrow rule correction.
Python finds a data file only from one folder: inspect cwd before changing the path
Compare the working directory with a source-file anchor, reproduce three launch locations and choose the right base for bundled data or caller input.
Git file history stops at a rename: read patches with one-path follow
Use a one-file rename fixture to distinguish commit lists, patches and path filtering, then inspect missing history without changing repository state.
Python subprocess arguments disappear with shell=True: check the POSIX boundary
Compare a direct argument list with POSIX shell=True, inspect actual received values and choose an explicit interpreter without guessing quoting.
pip freeze versus direct requirements: what an installed package list can tell you
Compare freeze, not-required graph roots and direct project requirements with an offline fixture, then verify a clean environment before changing the handoff.
pip externally-managed-environment: choose the project library or app target
Distinguish an externally managed base from project and application environments, inspect the actual interpreter and verify the intended installation target.
Empty submodule after git clone: initialize it and verify the recorded commit
Inspect Git submodule registration, populate an existing clone recursively and compare actual files and HEAD with the parent-recorded commit.
Python json has no loads attribute: inspect the imported file before reinstalling
Check the module file behind json, distinguish shadowing from installation failure and verify a local rename with a fresh-process JSON parse.
Git warns LF will become CRLF: inspect the index and working copy separately
Inspect Git line-ending reports, attributes and configuration, with verified LF index bytes and a CRLF working-copy checkout in a disposable repository.
pip installed the package but Python cannot import it: compare interpreters
Compare the failing Python executable, its pip inventory and the selected IDE environment, with a two-virtual-environment local reproduction.
jq defaults without overwriting false: choose null or missing-key behavior
Compare jq alternative, null-check and key-presence defaults using missing, null, false, true, zero and empty-string inputs.
curl returns HTTP 404 but exits 0: keep the body and check the right status
Separate curl transfer errors, HTTP error policy and strict-200 checks, with local 200, 201, 302 and 404 responses and saved-body verification.
Detached HEAD after checking out origin: preserve commits before switching
Distinguish checking out origin from a local branch, preserve a detached commit at its exact tip and verify a tracking branch in a local reproduction.
Deleted remote Git branch still listed? Preview pruning and keep local work
Distinguish local and remote-tracking branches, preview Git pruning and verify what remains, using a local bare-repository reproduction.