Removed redundant/unreachable code and added more tests.

src/deprecated.jl

@@ -228,11 +228,6 @@ function impute!(data::AbstractMatrix{Union{T, Missing}}, imp::Union{DropObs, Dr
     return data
 end
 
-function impute!(data::AbstractVector{Union{T, Missing}}, imp::Union{DropObs, DropVars}) where T
-    data = impute(data, imp)
-    return data
-end
-
 impute!(data, imp::Union{DropObs, DropVars}) = impute(data, imp)
 
 @deprecate impute(data, C::Chain) run(data, C) false

src/imputors/interp.jl

@@ -27,6 +27,7 @@ julia> impute(M, Interpolate(); dims=:rows)
 struct Interpolate <: Imputor end
 
 function _impute!(data::AbstractArray{<:Union{T, Missing}}, imp::Interpolate) where T
+    @assert !all(ismissing, data)
     i = findfirst(!ismissing, data) + 1
 
     while i < lastindex(data)

src/imputors/locf.jl

@@ -30,13 +30,9 @@ julia> impute(M, LOCF(); dims=:rows)
 struct LOCF <: Imputor end
 
 function _impute!(data::AbstractVector{Union{T, Missing}}, imp::LOCF) where T
-    start_idx = findfirst(!ismissing, data)
-    if start_idx === nothing
-        @debug "Cannot carry forward points when all values are missing"
-        return data
-    end
+    @assert !all(ismissing, data)
+    start_idx = findfirst(!ismissing, data) + 1
 
-    start_idx += 1
     for i in start_idx:lastindex(data)
         if ismissing(data[i])
             data[i] = data[i-1]

src/imputors/nocb.jl

@@ -31,13 +31,9 @@ julia> impute(M, NOCB(); dims=:rows)
 struct NOCB <: Imputor end
 
 function _impute!(data::AbstractVector{Union{T, Missing}}, imp::NOCB) where T
-    end_idx = findlast(!ismissing, data)
-    if end_idx === nothing
-        @debug "Cannot carry backward points when all values are missing"
-        return data
-    end
+    @assert !all(ismissing, data)
+    end_idx = findlast(!ismissing, data) - 1
 
-    end_idx -= 1
     for i in end_idx:-1:firstindex(data)
         if ismissing(data[i])
             data[i] = data[i+1]

test/chain.jl

@@ -1,4 +1,5 @@
 @testset "Chaining and Piping" begin
+    # TODO: Add tests at each section to double check that orig hasn't been overwritten.
     orig = Impute.dataset("test/table/neuro") |> DataFrame
 
     @testset "DataFrame" begin
@@ -122,4 +123,18 @@
         # Confirm that we don't have any more missing values
         @test all(!ismissing, result)
     end
+
+    @testset "Multi-type" begin
+        data = Impute.dataset("test/table/neuro") |> Tables.matrix
+        @test any(ismissing, data)
+        # Filter out colunns with more than 400 missing values, Fill with 0, and check that
+        # everything was replaced
+        C = Impute.Filter(c -> count(ismissing, c) < 400) ∘ Impute.Replace(; values=0.0) ∘ Impute.Threshold()
+
+        result = Impute.run(data, C; dims=:cols)
+        @test size(result, 1) == size(data, 1)
+        # We should have filtered out 1 column
+        @test size(result, 2) < size(data, 2)
+        @test all(!ismissing, result)
+    end
 end

test/data.jl

@@ -0,0 +1,14 @@
+@testset "data" begin
+    datasets = Impute.datasets()
+
+    @testset "Impute.dataset($name)" for name in datasets
+        result = Impute.dataset(name)
+        if contains(name, "matrix")
+            @test isa(result, AbstractDict)
+        elseif contains(name, "table")
+            @test isa(result, CSV.File)
+        end
+    end
+
+    @test_throws ArgumentError Impute.dataset("foobar")
+end

test/imputors/svd.jl

@@ -52,6 +52,8 @@
                 # Test having only missing data
                 c = missings(5, 2)
                 @test isequal(impute(c, tester.imp(; tester.kwargs...); dims=:cols), c)
+                c_ = tester.f!(deepcopy(c); dims=:cols)
+                @test isequal(c_, c)
             end
         end
         # Internal `svd` call isn't supported by these type, but maybe they should be?

test/testutils.jl

@@ -168,6 +168,8 @@ function test_matrix(tester::ImputorTester)
             # Test having only missing data
             c = missings(5, 2)
             @test isequal(impute(c, tester.imp(; tester.kwargs...); dims=:cols), c)
+            c_ = impute!(deepcopy(c), tester.imp(; tester.kwargs...); dims=:cols)
+            @test isequal(c_, c)
         end
     end
 end