Understand the failure.
Verify the repair.
Small, reproducible software failures. The broken implementation, the fix that didn’t work, and the one that passed—preserved together.
Explore the cases ↓How results are verified ↗WHAT THE ARCHIVE CONTAINS
100840 executable cases. 20168 are open.
Every case records the implementation that fails, the fix that did not work, and the repair that passed its checks—with recorded outputs and source hashes. This release adds 100840 cases across 20168 failure mechanisms and 254 domains.
The open tier gives you the failure and the unsuccessful fix for one case in every mechanism. The remaining 80672 cases, 5 variants per mechanism, are member-only: the verified repair, its recorded checks, and the full fixture suite are held in the member archive. Read the methodology ↗
A RECORD OF WHAT WENT WRONG
Browse the archive / 100840
Rook and queen polygon adjacency: neighbour scan range · case 01
Adjacency lists are one-sided: later polygons do not list earlier neighbours.
Rook and queen polygon adjacency: neighbour scan range · case 02
Adjacency lists are one-sided: later polygons do not list earlier neighbours.
Rook and queen polygon adjacency: neighbour scan range · case 03
Adjacency lists are one-sided: later polygons do not list earlier neighbours.
Rook and queen polygon adjacency: neighbour scan range · case 04
Adjacency lists are one-sided: later polygons do not list earlier neighbours.
Rook and queen polygon adjacency: neighbour scan range · case 05
Adjacency lists are one-sided: later polygons do not list earlier neighbours.
Rook and queen polygon adjacency: queen vertex contact · case 01
Polygons meeting only at a corner are missing from queen neighbours.
Rook and queen polygon adjacency: queen vertex contact · case 02
Polygons meeting only at a corner are missing from queen neighbours.
Rook and queen polygon adjacency: queen vertex contact · case 03
Polygons meeting only at a corner are missing from queen neighbours.
Rook and queen polygon adjacency: queen vertex contact · case 04
Polygons meeting only at a corner are missing from queen neighbours.
Rook and queen polygon adjacency: queen vertex contact · case 05
Polygons meeting only at a corner are missing from queen neighbours.
Rook and queen polygon adjacency: degenerate edge filter · case 01
Polygons with a repeated corner vertex become rook neighbours of anything sharing that corner.
Rook and queen polygon adjacency: degenerate edge filter · case 02
Polygons with a repeated corner vertex become rook neighbours of anything sharing that corner.
Rook and queen polygon adjacency: degenerate edge filter · case 03
Polygons with a repeated corner vertex become rook neighbours of anything sharing that corner.
Rook and queen polygon adjacency: degenerate edge filter · case 04
Polygons with a repeated corner vertex become rook neighbours of anything sharing that corner.
Rook and queen polygon adjacency: degenerate edge filter · case 05
Polygons with a repeated corner vertex become rook neighbours of anything sharing that corner.
Simple ring validity diagnosis: closing edge adjacency · case 01
Every valid ring is reported as self-intersecting.
Simple ring validity diagnosis: closing edge adjacency · case 02
Every valid ring is reported as self-intersecting.
Simple ring validity diagnosis: closing edge adjacency · case 03
Every valid ring is reported as self-intersecting.
Simple ring validity diagnosis: closing edge adjacency · case 04
Every valid ring is reported as self-intersecting.
Simple ring validity diagnosis: closing edge adjacency · case 05
Every valid ring is reported as self-intersecting.
Simple ring validity diagnosis: cyclic spike scan · case 01
Spikes located at the ring start vertex are reported as self-intersections.
Simple ring validity diagnosis: cyclic spike scan · case 02
Spikes located at the ring start vertex are reported as self-intersections.
Simple ring validity diagnosis: cyclic spike scan · case 03
Spikes located at the ring start vertex are reported as self-intersections.
Simple ring validity diagnosis: cyclic spike scan · case 04
Spikes located at the ring start vertex are reported as self-intersections.
Simple ring validity diagnosis: cyclic spike scan · case 05
Spikes located at the ring start vertex are reported as self-intersections.
Simple ring validity diagnosis: spike direction test · case 01
Rings with a redundant collinear vertex are rejected as spiky.
Simple ring validity diagnosis: spike direction test · case 02
Rings with a redundant collinear vertex are rejected as spiky.
Simple ring validity diagnosis: spike direction test · case 03
Rings with a redundant collinear vertex are rejected as spiky.
Simple ring validity diagnosis: spike direction test · case 04
Rings with a redundant collinear vertex are rejected as spiky.
Simple ring validity diagnosis: spike direction test · case 05
Rings with a redundant collinear vertex are rejected as spiky.
Simple ring validity diagnosis: cyclic repeated vertex · case 01
A ring whose closing position is doubled is diagnosed as a spike instead of a repeated point.
Simple ring validity diagnosis: cyclic repeated vertex · case 02
A ring whose closing position is doubled is diagnosed as a spike instead of a repeated point.
Simple ring validity diagnosis: cyclic repeated vertex · case 03
A ring whose closing position is doubled is diagnosed as a spike instead of a repeated point.
Simple ring validity diagnosis: cyclic repeated vertex · case 04
A ring whose closing position is doubled is diagnosed as a spike instead of a repeated point.
Simple ring validity diagnosis: cyclic repeated vertex · case 05
A ring whose closing position is doubled is diagnosed as a spike instead of a repeated point.
Simple ring validity diagnosis: collinear contact cases · case 01
Rings that touch themselves at a vertex or fold back along an edge are reported valid.
Simple ring validity diagnosis: collinear contact cases · case 02
Rings that touch themselves at a vertex or fold back along an edge are reported valid.
Simple ring validity diagnosis: collinear contact cases · case 03
Rings that touch themselves at a vertex or fold back along an edge are reported valid.
Simple ring validity diagnosis: collinear contact cases · case 04
Rings that touch themselves at a vertex or fold back along an edge are reported valid.
Simple ring validity diagnosis: collinear contact cases · case 05
Rings that touch themselves at a vertex or fold back along an edge are reported valid.
Hole placement validation against shell and siblings: shell contact allowance · case 01
Holes that touch the shell at a vertex are rejected as outside.
Hole placement validation against shell and siblings: shell contact allowance · case 02
Holes that touch the shell at a vertex are rejected as outside.
Hole placement validation against shell and siblings: shell contact allowance · case 03
Holes that touch the shell at a vertex are rejected as outside.
Hole placement validation against shell and siblings: shell contact allowance · case 04
Holes that touch the shell at a vertex are rejected as outside.
Hole placement validation against shell and siblings: shell contact allowance · case 05
Holes that touch the shell at a vertex are rejected as outside.
Hole placement validation against shell and siblings: every hole vertex tested · case 01
Holes that start inside the shell but cross out of it are accepted.
Hole placement validation against shell and siblings: every hole vertex tested · case 02
Holes that start inside the shell but cross out of it are accepted.
Hole placement validation against shell and siblings: every hole vertex tested · case 03
Holes that start inside the shell but cross out of it are accepted.
Hole placement validation against shell and siblings: every hole vertex tested · case 04
Holes that start inside the shell but cross out of it are accepted.
Hole placement validation against shell and siblings: every hole vertex tested · case 05
Holes that start inside the shell but cross out of it are accepted.
Hole placement validation against shell and siblings: nesting criterion · case 01
Duplicate or edge-sharing holes are reported as nested.
Hole placement validation against shell and siblings: nesting criterion · case 02
Duplicate or edge-sharing holes are reported as nested.
Hole placement validation against shell and siblings: nesting criterion · case 03
Duplicate or edge-sharing holes are reported as nested.
Hole placement validation against shell and siblings: nesting criterion · case 04
Duplicate or edge-sharing holes are reported as nested.
Hole placement validation against shell and siblings: nesting criterion · case 05
Duplicate or edge-sharing holes are reported as nested.
Hole placement validation against shell and siblings: coincident hole detection · case 01
Holes touching the shell at their first vertex are labelled coincident.
Hole placement validation against shell and siblings: coincident hole detection · case 02
Holes touching the shell at their first vertex are labelled coincident.
Hole placement validation against shell and siblings: coincident hole detection · case 03
Holes touching the shell at their first vertex are labelled coincident.
Hole placement validation against shell and siblings: coincident hole detection · case 04
Holes touching the shell at their first vertex are labelled coincident.
Hole placement validation against shell and siblings: coincident hole detection · case 05
Holes touching the shell at their first vertex are labelled coincident.
Hole placement validation against shell and siblings: outside short circuit · case 01
Hole reports have more labels than holes.
Hole placement validation against shell and siblings: outside short circuit · case 02
Hole reports have more labels than holes.
Hole placement validation against shell and siblings: outside short circuit · case 03
Hole reports have more labels than holes.
Hole placement validation against shell and siblings: outside short circuit · case 04
Hole reports have more labels than holes.
Hole placement validation against shell and siblings: outside short circuit · case 05
Hole reports have more labels than holes.
Grid snapping with ring collapse handling: half rounding direction · case 01
Coordinates exactly half-way between grid lines snap inconsistently.
Grid snapping with ring collapse handling: half rounding direction · case 02
Coordinates exactly half-way between grid lines snap inconsistently.
Grid snapping with ring collapse handling: half rounding direction · case 03
Coordinates exactly half-way between grid lines snap inconsistently.
Grid snapping with ring collapse handling: half rounding direction · case 04
Coordinates exactly half-way between grid lines snap inconsistently.
Grid snapping with ring collapse handling: half rounding direction · case 05
Coordinates exactly half-way between grid lines snap inconsistently.
Grid snapping with ring collapse handling: snapped duplicate merge · case 01
Snapped rings contain zero-length edges and collapsed rings survive.
Grid snapping with ring collapse handling: snapped duplicate merge · case 02
Snapped rings contain zero-length edges and collapsed rings survive.
Grid snapping with ring collapse handling: snapped duplicate merge · case 03
Snapped rings contain zero-length edges and collapsed rings survive.
Grid snapping with ring collapse handling: snapped duplicate merge · case 04
Snapped rings contain zero-length edges and collapsed rings survive.
Grid snapping with ring collapse handling: snapped duplicate merge · case 05
Snapped rings contain zero-length edges and collapsed rings survive.
Grid snapping with ring collapse handling: collapse threshold · case 01
Rings collapsed to a doubled segment are kept.
Grid snapping with ring collapse handling: collapse threshold · case 02
Rings collapsed to a doubled segment are kept.
Grid snapping with ring collapse handling: collapse threshold · case 03
Rings collapsed to a doubled segment are kept.
Grid snapping with ring collapse handling: collapse threshold · case 04
Rings collapsed to a doubled segment are kept.
Grid snapping with ring collapse handling: collapse threshold · case 05
Rings collapsed to a doubled segment are kept.
Grid snapping with ring collapse handling: hole collapse policy · case 01
A polygon disappears because one tiny hole collapsed.
Grid snapping with ring collapse handling: hole collapse policy · case 02
A polygon disappears because one tiny hole collapsed.
Grid snapping with ring collapse handling: hole collapse policy · case 03
A polygon disappears because one tiny hole collapsed.
Grid snapping with ring collapse handling: hole collapse policy · case 04
A polygon disappears because one tiny hole collapsed.
Grid snapping with ring collapse handling: hole collapse policy · case 05
A polygon disappears because one tiny hole collapsed.
Douglas-Peucker simplification of a topology arc: segment projection clamp · case 01
Vertices that overshoot the end of the base segment are dropped as if they lay on it.
Douglas-Peucker simplification of a topology arc: segment projection clamp · case 02
Vertices that overshoot the end of the base segment are dropped as if they lay on it.
Douglas-Peucker simplification of a topology arc: segment projection clamp · case 03
Vertices that overshoot the end of the base segment are dropped as if they lay on it.
Douglas-Peucker simplification of a topology arc: segment projection clamp · case 04
Vertices that overshoot the end of the base segment are dropped as if they lay on it.
Douglas-Peucker simplification of a topology arc: segment projection clamp · case 05
Vertices that overshoot the end of the base segment are dropped as if they lay on it.
Douglas-Peucker simplification of a topology arc: coincident endpoints · case 01
Closed arcs collapse to a single point.
Douglas-Peucker simplification of a topology arc: coincident endpoints · case 02
Closed arcs collapse to a single point.
Douglas-Peucker simplification of a topology arc: coincident endpoints · case 03
Closed arcs collapse to a single point.
Douglas-Peucker simplification of a topology arc: coincident endpoints · case 04
Closed arcs collapse to a single point.
Douglas-Peucker simplification of a topology arc: coincident endpoints · case 05
Closed arcs collapse to a single point.
Douglas-Peucker simplification of a topology arc: tolerance comparison · case 01
Vertices exactly at the tolerance are retained.
Douglas-Peucker simplification of a topology arc: tolerance comparison · case 02
Vertices exactly at the tolerance are retained.
Douglas-Peucker simplification of a topology arc: tolerance comparison · case 03
Vertices exactly at the tolerance are retained.
Douglas-Peucker simplification of a topology arc: tolerance comparison · case 04
Vertices exactly at the tolerance are retained.
Douglas-Peucker simplification of a topology arc: tolerance comparison · case 05
Vertices exactly at the tolerance are retained.
INSPECTABLE BY DESIGN
Every result has a runnable source.
Runnable implementations with recorded outputs, source hashes, and explicit contracts. Related variants share a failure mechanism and belong together in evaluation splits.
Read the methodology ↗