Move logic to parallel text corpus

[Enkidu93]

When creating a ParallelTextCorpus, if target has no references, make target references source references changed to target versification.

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This change is 

[ddaspit]

Does this now mean that ParallelTextRow.TargetRefs will never be empty for Scripture? If so, we should update the return type for CorporaExtensions.ExtractScripture so that CorpusVerseRef is not nullable.

Reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @Enkidu93)

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tests/SIL.Machine.Tests/Corpora/CorporaExtensionsTests.cs line 20 at r1 (raw file):

            Assert.That(text, Is.EqualTo(""));
            Assert.That(origRef, Is.EqualTo(new VerseRef("GEN 1:1", ScrVers.Original)));
            Assert.That(corpusRef.HasValue, Is.False);

Since corpusRef now has a value, can you add an assert for the correct value?

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tests/SIL.Machine.Tests/Corpora/CorporaExtensionsTests.cs line 35 at r1 (raw file):

            Assert.That(text, Is.EqualTo("<range>"));
            Assert.That(origRef, Is.EqualTo(new VerseRef("1CH 12:4", ScrVers.Original)));
            Assert.That(corpusRef.HasValue, Is.False);

Since corpusRef now has a value, can you add an assert for the correct value?

[Enkidu93]

Yes, done - should be

Reviewable status: 2 of 4 files reviewed, 2 unresolved discussions (waiting on @ddaspit)

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tests/SIL.Machine.Tests/Corpora/CorporaExtensionsTests.cs line 20 at r1 (raw file):

Previously, ddaspit (Damien Daspit) wrote…

Since corpusRef now has a value, can you add an assert for the correct value?

Done

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tests/SIL.Machine.Tests/Corpora/CorporaExtensionsTests.cs line 35 at r1 (raw file):

Previously, ddaspit (Damien Daspit) wrote…

Since corpusRef now has a value, can you add an assert for the correct value?

Done

[ddaspit]

Reviewed 2 of 2 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @Enkidu93)