Show the fill value when it isn't the default

docs/src/arrays.md

@@ -90,6 +90,7 @@ julia> v = GBVector{ComplexF32}(100)
 julia> v = GBMatrix(ComplexF64[1, 2im, 3 + 4im]; fill = nothing)
 3x1 GraphBLAS double complex matrix, full by col
   3 entries, memory: 288 bytes
+  fill value:  nothing
 
     (1,1)    1 + 0i
     (2,1)    0 + 2i

docs/src/examples.md

@@ -46,6 +46,7 @@ julia> cohen(A), sandia(A)
 julia> bfs_parents(A, 1, 5)
 5x1 GraphBLAS int64_t matrix, bitmap by col
   5 entries, memory: 288 bytes
+  fill value:  nothing
 
     (1,1)   0
     (2,1)   1

docs/src/index.md

@@ -90,6 +90,7 @@ true
 julia> B = setfill(A, missing) # no-copy alias
 1000x1000 GraphBLAS double complex matrix, hypersparse by row, ints: 32/32/32
   no entries, memory: 256 bytes
+  fill value:  missing
 
 julia> B[1, 1]
 missing

src/abstractgbarray.jl

@@ -1019,14 +1019,23 @@ function Base.setindex!(
 end
 
 function Base.show(io::IO, ::MIME"text/plain", A::AbstractGBArray) #fallback printing
-    gxbprint(io, A)
+    str = gxbstring(A)
+    fill = getfill(A)
+    if !isequal(fill, defaultfill(storedeltype(A)))
+        # insert the fill value after the two GraphBLAS header lines, or append it
+        line = "  fill value:  $fill\n"
+        i = findfirst('\n', str)
+        i = i === nothing ? nothing : findnext('\n', str, i + 1)
+        str = i === nothing ? string(chomp(str), '\n', line) : str[1:i] * line * str[i+1:end]
+    end
+    print(io, str)
 end
 
 function Base.show(io::IO, A::AbstractGBArray)
-    gxbprint(io, A)
+    show(io, MIME"text/plain"(), A)
 end
 function Base.show(io::IOContext, A::AbstractGBArray)
-    gxbprint(io, A)
+    show(io, MIME"text/plain"(), A)
 end
 
 

test/gbarray.jl

@@ -35,6 +35,9 @@
             @test A'[1, 2] == 2
             deleteat!(A, 1, 1)
             @test A[1, 1] == getfill(A)
+            # #104: non-default fill shows up in show
+            @test !occursin("fill value", sprint(show, MIME"text/plain"(), A))
+            @test occursin("fill value:  17", sprint(show, MIME"text/plain"(), setfill(A, 17)))
         end
         @testset "sparse" begin
             #Construction and indexing correct for sparse matrices