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
Address display casing: two-letter directionals are title-cased · case 01
"NE" prints as "Ne".
Address display casing: two-letter directionals are title-cased · case 02
"NE" prints as "Ne".
Address display casing: two-letter directionals are title-cased · case 03
"NE" prints as "Ne".
Address display casing: two-letter directionals are title-cased · case 04
"NE" prints as "Ne".
Address display casing: two-letter directionals are title-cased · case 05
"NE" prints as "Ne".
Address completeness checker: whitespace-only values count as present · case 01
A city consisting of a tab passes the check.
Address completeness checker: whitespace-only values count as present · case 02
A city consisting of a tab passes the check.
Address completeness checker: whitespace-only values count as present · case 03
A city consisting of a tab passes the check.
Address completeness checker: whitespace-only values count as present · case 04
A city consisting of a tab passes the check.
Address completeness checker: whitespace-only values count as present · case 05
A city consisting of a tab passes the check.
Address completeness checker: duplicate second lines differing in case are missed · case 01
"21 FAKE RD" as line2 under "21 Fake Rd" is not reported.
Address completeness checker: duplicate second lines differing in case are missed · case 02
"21 FAKE RD" as line2 under "21 Fake Rd" is not reported.
Address completeness checker: duplicate second lines differing in case are missed · case 03
"21 FAKE RD" as line2 under "21 Fake Rd" is not reported.
Address completeness checker: duplicate second lines differing in case are missed · case 04
"21 FAKE RD" as line2 under "21 Fake Rd" is not reported.
Address completeness checker: duplicate second lines differing in case are missed · case 05
"21 FAKE RD" as line2 under "21 Fake Rd" is not reported.
Address completeness checker: region rules applied to BB · case 01
BB addresses without a region are reported as region_missing.
Address completeness checker: region rules applied to BB · case 02
BB addresses without a region are reported as region_missing.
Address completeness checker: region rules applied to BB · case 03
BB addresses without a region are reported as region_missing.
Address completeness checker: region rules applied to BB · case 04
BB addresses without a region are reported as region_missing.
Address completeness checker: region rules applied to BB · case 05
BB addresses without a region are reported as region_missing.
Address completeness checker: region shape checks only length · case 01
Region "Z9" is accepted.
Address completeness checker: region shape checks only length · case 02
Region "Z9" is accepted.
Address completeness checker: region shape checks only length · case 03
Region "Z9" is accepted.
Address completeness checker: region shape checks only length · case 04
Region "Z9" is accepted.
Address completeness checker: region shape checks only length · case 05
Region "Z9" is accepted.
Address completeness checker: BB codes are measured against the AA length · case 01
Valid four-digit BB codes are reported invalid.
Address completeness checker: BB codes are measured against the AA length · case 02
Valid four-digit BB codes are reported invalid.
Address completeness checker: BB codes are measured against the AA length · case 03
Valid four-digit BB codes are reported invalid.
Address completeness checker: BB codes are measured against the AA length · case 04
Valid four-digit BB codes are reported invalid.
Address completeness checker: BB codes are measured against the AA length · case 05
Valid four-digit BB codes are reported invalid.
Address completeness checker: codes supplied for CC are not reported · case 01
A CC address with postal "9919" returns no issues.
Address completeness checker: codes supplied for CC are not reported · case 02
A CC address with postal "9919" returns no issues.
Address completeness checker: codes supplied for CC are not reported · case 03
A CC address with postal "9919" returns no issues.
Address completeness checker: codes supplied for CC are not reported · case 04
A CC address with postal "9919" returns no issues.
Address completeness checker: codes supplied for CC are not reported · case 05
A CC address with postal "9919" returns no issues.
Address completeness checker: a blank code is reported both missing and invalid · case 01
A blank AA code yields postal_missing and postal_invalid.
Address completeness checker: a blank code is reported both missing and invalid · case 02
A blank AA code yields postal_missing and postal_invalid.
Address completeness checker: a blank code is reported both missing and invalid · case 03
A blank AA code yields postal_missing and postal_invalid.
Address completeness checker: a blank code is reported both missing and invalid · case 04
A blank AA code yields postal_missing and postal_invalid.
Address completeness checker: a blank code is reported both missing and invalid · case 05
A blank AA code yields postal_missing and postal_invalid.
Ten-digit display formatter: any eleventh leading digit is stripped · case 01
"2" followed by a valid ten-digit number is accepted with the 2 discarded.
Ten-digit display formatter: any eleventh leading digit is stripped · case 02
"2" followed by a valid ten-digit number is accepted with the 2 discarded.
Ten-digit display formatter: any eleventh leading digit is stripped · case 03
"2" followed by a valid ten-digit number is accepted with the 2 discarded.
Ten-digit display formatter: any eleventh leading digit is stripped · case 04
"2" followed by a valid ten-digit number is accepted with the 2 discarded.
Ten-digit display formatter: any eleventh leading digit is stripped · case 05
"2" followed by a valid ten-digit number is accepted with the 2 discarded.
Ten-digit display formatter: service-code area codes are accepted · case 01
"211-555-0115" formats as a normal number.
Ten-digit display formatter: service-code area codes are accepted · case 02
"211-555-0115" formats as a normal number.
Ten-digit display formatter: service-code area codes are accepted · case 03
"211-555-0115" formats as a normal number.
Ten-digit display formatter: service-code area codes are accepted · case 04
"211-555-0115" formats as a normal number.
Ten-digit display formatter: service-code area codes are accepted · case 05
"211-555-0115" formats as a normal number.
Ten-digit display formatter: area codes starting with 1 are accepted · case 01
An exchange or area beginning with 1 is formatted instead of rejected.
Ten-digit display formatter: area codes starting with 1 are accepted · case 02
An exchange or area beginning with 1 is formatted instead of rejected.
Ten-digit display formatter: area codes starting with 1 are accepted · case 03
An exchange or area beginning with 1 is formatted instead of rejected.
Ten-digit display formatter: area codes starting with 1 are accepted · case 04
An exchange or area beginning with 1 is formatted instead of rejected.
Ten-digit display formatter: area codes starting with 1 are accepted · case 05
An exchange or area beginning with 1 is formatted instead of rejected.
Ten-digit display formatter: dotted numbers are rejected · case 01
"302.555.0115" returns None.
Ten-digit display formatter: dotted numbers are rejected · case 02
"302.555.0115" returns None.
Ten-digit display formatter: dotted numbers are rejected · case 03
"302.555.0115" returns None.
Ten-digit display formatter: dotted numbers are rejected · case 04
"302.555.0115" returns None.
Ten-digit display formatter: dotted numbers are rejected · case 05
"302.555.0115" returns None.
Ten-digit display formatter: a plus sign with the wrong country is accepted · case 01
"+3025550115" formats as a domestic number although its country digit is missing.
Ten-digit display formatter: a plus sign with the wrong country is accepted · case 02
"+3025550115" formats as a domestic number although its country digit is missing.
Ten-digit display formatter: a plus sign with the wrong country is accepted · case 03
"+3025550115" formats as a domestic number although its country digit is missing.
Ten-digit display formatter: a plus sign with the wrong country is accepted · case 04
"+3025550115" formats as a domestic number although its country digit is missing.
Ten-digit display formatter: a plus sign with the wrong country is accepted · case 05
"+3025550115" formats as a domestic number although its country digit is missing.
E.164 parser with trunk prefixes: the first matching country code wins · case 01
"+83..." is parsed as country 8 with a national number starting with 3.
E.164 parser with trunk prefixes: the first matching country code wins · case 02
"+83..." is parsed as country 8 with a national number starting with 3.
E.164 parser with trunk prefixes: the first matching country code wins · case 03
"+83..." is parsed as country 8 with a national number starting with 3.
E.164 parser with trunk prefixes: the first matching country code wins · case 04
"+83..." is parsed as country 8 with a national number starting with 3.
E.164 parser with trunk prefixes: the first matching country code wins · case 05
"+83..." is parsed as country 8 with a national number starting with 3.
E.164 parser with trunk prefixes: the 00 prefix is kept in the digits · case 01
"0083 ..." matches no country and returns None.
E.164 parser with trunk prefixes: the 00 prefix is kept in the digits · case 02
"0083 ..." matches no country and returns None.
E.164 parser with trunk prefixes: the 00 prefix is kept in the digits · case 03
"0083 ..." matches no country and returns None.
E.164 parser with trunk prefixes: the 00 prefix is kept in the digits · case 04
"0083 ..." matches no country and returns None.
E.164 parser with trunk prefixes: the 00 prefix is kept in the digits · case 05
"0083 ..." matches no country and returns None.
E.164 parser with trunk prefixes: the trunk digit is not removed · case 01
National input "0555..." keeps its trunk zero and fails the length check.
E.164 parser with trunk prefixes: the trunk digit is not removed · case 02
National input "0555..." keeps its trunk zero and fails the length check.
E.164 parser with trunk prefixes: the trunk digit is not removed · case 03
National input "0555..." keeps its trunk zero and fails the length check.
E.164 parser with trunk prefixes: the trunk digit is not removed · case 04
National input "0555..." keeps its trunk zero and fails the length check.
E.164 parser with trunk prefixes: the trunk digit is not removed · case 05
National input "0555..." keeps its trunk zero and fails the length check.
E.164 parser with trunk prefixes: national numbers without the trunk are silently shortened · case 01
A ten-digit AA number without its trunk loses its first digit and is accepted.
E.164 parser with trunk prefixes: national numbers without the trunk are silently shortened · case 02
A ten-digit AA number without its trunk loses its first digit and is accepted.
E.164 parser with trunk prefixes: national numbers without the trunk are silently shortened · case 03
A ten-digit AA number without its trunk loses its first digit and is accepted.
E.164 parser with trunk prefixes: national numbers without the trunk are silently shortened · case 04
A ten-digit AA number without its trunk loses its first digit and is accepted.
E.164 parser with trunk prefixes: national numbers without the trunk are silently shortened · case 05
A ten-digit AA number without its trunk loses its first digit and is accepted.
E.164 parser with trunk prefixes: the "(0)" notation keeps its zero · case 01
"+42 (0)55501..." has one digit too many and is rejected.
E.164 parser with trunk prefixes: the "(0)" notation keeps its zero · case 02
"+42 (0)55501..." has one digit too many and is rejected.
E.164 parser with trunk prefixes: the "(0)" notation keeps its zero · case 03
"+42 (0)55501..." has one digit too many and is rejected.
E.164 parser with trunk prefixes: the "(0)" notation keeps its zero · case 04
"+42 (0)55501..." has one digit too many and is rejected.
E.164 parser with trunk prefixes: the "(0)" notation keeps its zero · case 05
"+42 (0)55501..." has one digit too many and is rejected.
E.164 parser with trunk prefixes: international numbers are measured with the caller region lengths · case 01
"+83" plus ten digits is rejected when the default region is AA.
E.164 parser with trunk prefixes: international numbers are measured with the caller region lengths · case 02
"+83" plus ten digits is rejected when the default region is AA.
E.164 parser with trunk prefixes: international numbers are measured with the caller region lengths · case 03
"+83" plus ten digits is rejected when the default region is AA.
E.164 parser with trunk prefixes: international numbers are measured with the caller region lengths · case 04
"+83" plus ten digits is rejected when the default region is AA.
E.164 parser with trunk prefixes: international numbers are measured with the caller region lengths · case 05
"+83" plus ten digits is rejected when the default region is AA.
Variable-length area code grouping: the shortest matching area code is used · case 01
"04012 ..." is grouped as area 040.
Variable-length area code grouping: the shortest matching area code is used · case 02
"04012 ..." is grouped as area 040.
Variable-length area code grouping: the shortest matching area code is used · case 03
"04012 ..." is grouped as area 040.
Variable-length area code grouping: the shortest matching area code is used · case 04
"04012 ..." is grouped as area 040.
Variable-length area code grouping: the shortest matching area code is used · case 05
"04012 ..." is grouped as area 040.
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 ↗