Hom of CoherentSheaf on a NormalToricVariety fails due to a missing pruningMap
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Description
```macaulay2
needsPackage "NormalToricVarieties"
X = hirzebruchSurface 3
Hom(OO_X(1,0),OO_X(0,0))
```
This call to Hom fails since it expects prune of a sheaf map to always populate `H.cache.pruningMap`. In this case, `prune sheafHom(OO_X(1,0),OO_X(0,0))` doesn't. I think this is because the hook for minimalPresentation for normal toric varieties doesn't populate this field.
See: https://github.com/Macaulay2/M2/blob/1a37f6fe95badb1e5f99707a485503d213fd9d49/M2/Macaulay2/packages/Varieties/SheafMaps.m2#L445
@mahrud
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Research direction
Reproduce the failure with the NormalToricVarieties package using the Hirzebruch surface and Hom example in the issue. Read the prune/sheafHom handling at Varieties/SheafMaps.m2 around line 445 and inspect the minimalPresentation hook for normal toric varieties. Done means the Hom call succeeds and the pruningMap is populated.
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- Issue type
- Bug
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