tests/testthat/test-chartr.R

In Bioconductor/Biostrings: Efficient manipulation of biological strings

## chartr.R exports the following:
## - chartr
## - replaceAmbiguities
##
## chartr() is defined for XString, XStringSet,
## XStringViews, MaskedXString


test_that("chartr has correct behavior on Biostrings objects", {
    s1 <- BString("apple AppLE potato")
    s2 <- BString("peels AeeLE eotpto")
    expect_true(chartr("apple", "peels", s1) == s2)
    expect_true(all(chartr("apple", "peels", BStringSet(list(s1,s1))) ==
                    BStringSet(list(s2,s2))))

    v1 <- Views(s1, start=c(1,7,13), width=c(5,5,6))
    v2 <- Views(s2, start=c(1,7,13), width=c(5,5,6))
    expect_equal(as.character(chartr("apple", "peels", v1)), as.character(v2))

    ## will break when we implement this to remind me to write tests
    ms1 <- s1
    ms2 <- s2
    m1 <- Mask(length(s1), start=7, width=5)
    masks(ms1) <- m1
    expect_error(chartr("apple", "peels", ms1), "Please complain!")
})

test_that("replaceAmbiguities works as expected", {
    dna1 <- DNAString(paste(DNA_ALPHABET, collapse=""))
    dna2 <- DNAString(paste(c(DNA_BASES, rep("N", length(dna1)-7L), "-+."),
                            collapse=""))

    expect_equal(replaceAmbiguities(dna1), dna2)
    expect_equal(replaceAmbiguities(as(dna1, "RNAString")),
                                    as(dna2, "RNAString"))

    aa <- AAString(paste(AA_ALPHABET, collapse=""))
    bb <- BString(paste(LETTERS, collapse=""))
    expect_error(replaceAmbiguities(aa), "only supported for DNA and RNA")
    expect_error(replaceAmbiguities(bb), "only supported for DNA and RNA")
    expect_error(replaceAmbiguities("test"), "only supported for DNA and RNA")

    expect_true(all(replaceAmbiguities(DNAStringSet(list(dna1, dna1))) ==
                    DNAStringSet(list(dna2, dna2))))
    expect_true(all(replaceAmbiguities(Views(dna1, start=c(1,4,7), width=3)) ==
                    Views(dna2, start=c(1,4,7), width=3)))
})