## [1.27.0] - 2026-07-29

Core modify gap-fillers: the six commands every AutoCAD user reaches
for, now
native to the CAD dock. The toolset grows from 33 to 39 tools.

### Added
- **Chamfer** (`CHA`) — straight distance-distance corner cut between
two lines. Enter both cutbacks (or tick *equal distances*), pick the
two lines, and the tool trims both to the corner and adds the chamfer
segment, all in one undo step. A live dashed hover preview shows the
cut before you commit, and a cutback longer than the retained leg is
rejected instead of corrupting the source line. Distances stay
metre-accurate in geographic projects.
- **Break** (`BR`) — split a line at a picked point, or remove the
span between two picked points. Enter or right-click after the first
point breaks there with no gap. The picked feature keeps the first
part; the remainder is added with the same attributes. Intermediate
polyline vertices survive the split, and a break on an endpoint is
refused.
- **Lengthen** (`LEN`) — change a line by delta, percent, or total
length. The end you click is the end that moves, extension follows the
terminal segment direction, and shortening trims cleanly through
intermediate vertices.
- **Align** (`AL`) — move and rotate a feature onto source/destination
point pairs, with optional scaling by the pair length ratio. Enter
after the first pair moves without rotating. Curves and Z/M values
survive because the whole operation is a single affine transform.
- **Stretch** (`S`) — drag a crossing window, pick a base and target
point, and only the vertices inside the window move. Every editable
layer crossing the window is stretched in one pass, and polygon rings
stay closed.
- **Explode** (`X`) — split a multipart feature into single parts, or
a line/polygon boundary into single segments. Polygon segments
(including interior rings) are written to a managed `planx_explode`
line layer, and removing the source feature is optional.
- All six commands join the command line, the command palette, the
shortcut guide, the tool hints, and the in-app command reference.

### Changed
- `CHAMFER` and `CHA` now start the general two-line Chamfer tool,
matching AutoCAD. The urban Block Chamfer keeps its own `BLOCK` and
`BLOCKCHAMFER` aliases.
- The command palette alias for Extend changed from `lengthen` to
`extend to boundary`, so it no longer collides with the new Lengthen
command.

### Compatibility
- Managed memory layers now declare their schema in the provider URI
instead of building `QgsField` objects, removing the last `QVariant`
usage from the plugin. PyQt6 dropped `QVariant.Type`, and the Hub's
Qt6 checker flags `QVariant` regardless, while the
`QgsField(QMetaType)` alternative would have required QGIS 3.38 and
broken the 3.28 floor.

### Quality
- New `tests/smoke_modify_geometry.py`: 21 geometry checks for the
chamfer, break, lengthen, align, stretch, and explode helpers,
verified on QGIS 3.44 LTR and QGIS 4.2.
- `tests/smoke_runtime.py` grew from 20 to 30 checks, including
layer-write verification for each new tool (edit commands, part
creation, and managed output layers) and a guarantee that every
registered tool key has a dock button.
- `tests/smoke_compat.py` now enforces that every command alias
resolves to a real tool key, so a future rename cannot leave an alias
silently dead.

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