Basic all around fixes

src/axioms.jl

@@ -98,12 +98,25 @@ function (si::SpectralIndex)(args::Number...)
     return arg_type(result)
 end
 
-function Base.show(io::IO, index::SpectralIndex)
-    println(io, index.short_name, ": ", index.long_name)
-    println(io, "Application domain: ", index.application_domain)
-    println(io, "Bands/Parameters: ", index.bands)
-    println(io, "Formula: ", index.formula)
-    return println(io, "Reference: ", index.reference)
+# Machine-readable output
+function Base.show(io::IO, si::SpectralIndex)
+    print(io, "SpectralIndex(")
+    println(io, "short_name: $(si.short_name),")
+    println(io, "long_name: $(si.long_name),")
+    println(io, "application_domain: $(si.application_domain),")
+    println(io, "bands: $(si.bands),")
+    println(io, "formula: $(si.formula),")
+    println(io, "reference: $(si.reference)")
+    return println(io, ")")
+end
+
+# Human-readable output
+function Base.show(io::IO, ::MIME"text/plain", si::SpectralIndex)
+    println(io, "$(si.short_name): $(si.long_name)")
+    println(io, "* Application Domain: $(si.application_domain)")
+    println(io, "* Bands/Parameters: $(si.bands)")
+    println(io, "* Formula: $(si.formula)")
+    return println(io, "* Reference: $(si.reference)")
 end
 
 """

src/utils.jl

@@ -54,11 +54,15 @@ indices = _get_indices(true)
 '''
 ```
 """
-function _get_indices(online::Bool=false)
+function _get_indices(
+    online::Bool=false;
+    filename="spectral-indices-dict.json",
+    fileloc=joinpath(dirname(@__FILE__), "..", "data", filename),
+)
     if online
         indices_loc = Downloads.download(
             "https://raw.githubusercontent.com/awesome-spectral-indices/awesome-spectral-indices/main/output/spectral-indices-dict.json",
-            string(pwd(), "spectral-indices-dict.json"),
+            fileloc,
         )
         indices = JSON.parsefile(indices_loc)
     else

test/axioms.jl

@@ -29,3 +29,27 @@ C_vals = fill(0.6, 5)
 I_vals = fill(0.2, 5)
 computed_array_index = si.(C_vals, I_vals)
 @test all(computed_array_index .≈ 0.5)
+
+# Test Human-readable Output
+@test begin
+    io_buffer = IOBuffer()
+    show(io_buffer, MIME("text/plain"), si)
+    human_readable_output = String(take!(io_buffer))
+    expected_human_readable_output = """
+    CI: Custom Index
+    * Application Domain: Vegetation
+    * Bands/Parameters: ["C", "I"]
+    * Formula: (C-I)/(C+I)
+    * Reference: Doe et al., 1984
+    """
+    human_readable_output == expected_human_readable_output
+end
+
+# Test Machine-readable Output
+@test begin
+    io_buffer = IOBuffer()
+    show(io_buffer, si)
+    machine_readable_output = String(take!(io_buffer))
+    expected_machine_readable_output = "SpectralIndex(short_name: CI,\nlong_name: Custom Index,\napplication_domain: Vegetation,\nbands: [\"C\", \"I\"],\nformula: (C-I)/(C+I),\nreference: Doe et al., 1984\n)\n"
+    machine_readable_output == expected_machine_readable_output
+end

test/utils.jl

@@ -8,7 +8,25 @@ using SpectralIndices
 # Test offline
 @test SpectralIndices._get_indices() isa Dict
 # Test online
-@test SpectralIndices._get_indices(true) isa Dict
+@testset "Download Indices Test" begin
+    test_dir = mktempdir()
+    try
+        # Define the file location within the test directory
+        test_fileloc = joinpath(test_dir, "spectral-indices-dict.json")
+
+        # Run the _get_indices function with online = true
+        indices = SpectralIndices._get_indices(true; fileloc=test_fileloc)
+
+        # Test if the file was downloaded and parsed successfully
+        @test isfile(test_fileloc)
+        @test !isempty(indices)
+        @test indices isa Dict
+
+    finally
+        # Clean up: Delete the test file and directory
+        rm(test_dir; recursive=true)
+    end
+end
 
 params = Dict("N" => 0.6, "R" => 0.3)
 # Test correctness