MDEV-34079: ST_AsGeoJSON returns incorrect value for empty geometry#4738
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abhishek593 wants to merge 1 commit intoMariaDB:10.11from
Open
MDEV-34079: ST_AsGeoJSON returns incorrect value for empty geometry#4738abhishek593 wants to merge 1 commit intoMariaDB:10.11from
abhishek593 wants to merge 1 commit intoMariaDB:10.11from
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ST_AsGeoJSON stripped the first '[' bracket when serializing an EMPTY
GeometryCollection, outputting '{"type": "GeometryCollection",
"geometries":]}'.
This occurred because several Gis_*::get_data_as_json functions
unconditionally truncated the last 2 characters of their String buffer
to remove the trailing ', ' appended inside their element loops. For
empty collections, the loop doesn't execute and there is no trailing
comma, causing the truncate to strip the initial '[' bracket.
Fixed by checking if the last character in the buffer is ' ' before
truncating.
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Thank you for your contribution! This is a preliminary review.
| txt->qs_append(", ", 2); | ||
| } | ||
| txt->length(txt->length() - 2);// Remove ending ', ' | ||
| if (txt->ptr()[txt->length() - 1] == ' ') |
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I'd be more comfortable if you save and check n_points instead. Here and everyplace else you are changing.
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ST_AsGeoJSON stripped the first '[' bracket when serializing an EMPTY GeometryCollection, outputting '{"type": "GeometryCollection", "geometries":]}'.
This occurred because several Gis_*::get_data_as_json functions unconditionally truncated the last 2 characters of their String buffer to remove the trailing ', ' appended inside their element loops. For empty collections, the loop doesn't execute and there is no trailing comma, causing the truncate to strip the initial '[' bracket.
Fixed by checking if the last character in the buffer is ' ' before truncating.