Generating new arrays with $append/$prepend

[TobiasNx]

We should reintroduce $append and $prepend as creation methods if the array does not exist in a record to add to or create an array.

Was part of: #111
Related to: #93 and #92

[fsteeg]

Will revisit after #102.

Functional review: @TobiasNx
Code review: @blackwinter / @fsteeg

[TobiasNx]

Since this is standard behaviour of Catmandu fix I would like when this gets prioritized over other fix tickets.

[blackwinter]

Integration tests:

• add_fieldAppendAndCreateArrayOfObjectsInArrayOfObjects
• add_fieldAppendAndCreateArrayOfObjects
• add_fieldAppendAndCreateArrayOfStringsInArrayOfObjects
• add_fieldAppendAndCreateArrayOfStrings
• add_fieldAppendAndCreateNestedArrayOfObjects
• add_fieldAppendAndCreateNestedArrayOfStrings
• add_fieldPrependAndCreateArray
• copy_fieldAppendAndCreateArrayOfObjectsInArrayOfObjects
• copy_fieldAppendAndCreateArrayOfObjects
• copy_fieldAppendAndCreateArrayOfStringsInArrayOfObjects
• copy_fieldAppendAndCreateArrayOfStrings
• copy_fieldAppendAndCreateNestedArrayOfObjects
• copy_fieldAppendAndCreateNestedArrayOfStrings
• copy_fieldPrependAndCreateArray
• move_fieldAppendAndCreateArrayOfObjectsInArrayOfObjects
• move_fieldAppendAndCreateArrayOfObjects
• move_fieldAppendAndCreateArrayOfStringsInArrayOfObjects
• move_fieldAppendAndCreateArrayOfStrings
• move_fieldAppendAndCreateNestedArrayOfObjects
• move_fieldAppendAndCreateNestedArrayOfStrings
• move_fieldPrependAndCreateArray

[TobiasNx]

It seems that this would "only" need adjustment in two code segments, but I could be wrong:

metafacture-fix/metafix/src/main/java/org/metafacture/metafix/FixPath.java

Lines 173 to 175 in 5561729

	case $append:
	array.add(value);
	break;

metafacture-fix/metafix/src/main/java/org/metafacture/metafix/FixPath.java

Lines 342 to 345 in 5561729

	case $append:
	referencedValue = Value.newHash().withPathSet(p); // TODO: append non-hash?
	array.add(referencedValue);
	break;

[fsteeg]

Ready for functional review in branch 127-arrays.

[fsteeg]

Changes in PR should be done, could you test again with current branch 127-arrays?

[TobiasNx]

I tried lobid-resources and all tests did run trough without changes +1