Add download tests

src/tzdata/download.jl

@@ -82,7 +82,8 @@ function tzdata_download(version::AbstractString="latest", dir::AbstractString=t
     if version == "latest"
         v = latest_version(now_utc)
         if !isnull(v)
-            return joinpath(dir, "tzdata$(unsafe_get(v)).tar.gz")
+            archive = joinpath(dir, "tzdata$(unsafe_get(v)).tar.gz")
+            isfile(archive) && return archive
         end
     end
 

test/helpers.jl

@@ -0,0 +1,28 @@
+# Utility functions for testing
+
+function ignore_output(body::Function; stdout::Bool=true, stderr::Bool=true)
+    out_old = STDOUT
+    err_old = STDERR
+
+    if stdout
+        (out_rd, out_wr) = redirect_stdout()
+    end
+    if stderr
+        (err_rd, err_wr) = redirect_stderr()
+    end
+
+    result = body()
+
+    if stdout
+        redirect_stdout(out_old)
+        close(out_wr)
+        close(out_rd)
+    end
+    if stderr
+        redirect_stderr(err_old)
+        close(err_wr)
+        close(err_rd)
+    end
+
+    return result
+end

test/runtests.jl

@@ -37,10 +37,13 @@ for name in TEST_REGIONS
     tzdata[name] = tzparse(joinpath(TZ_SOURCE_DIR, name))
 end
 
+include("helpers.jl")
+
 include("utils.jl")
 include(joinpath("tzdata", "timeoffset.jl"))
 include(joinpath("tzdata", "archive.jl"))
 include(joinpath("tzdata", "version.jl"))
+include(joinpath("tzdata", "download.jl"))
 include(joinpath("tzdata", "compile.jl"))
 include("utcoffset.jl")
 include("types.jl")

test/tzdata/download.jl

@@ -0,0 +1,24 @@
+import TimeZones.TZData: tzdata_url, tzdata_download, isarchive
+
+@test tzdata_url("2016j") == "https://www.iana.org/time-zones/repository/releases/tzdata2016j.tar.gz"
+@test tzdata_url("latest") == "https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz"
+
+# Note: Try to keep the number of `tzdata_download` calls low to avoid unnecessary network traffic
+mktempdir() do temp_dir
+    file_path = ignore_output() do
+        tzdata_download("latest", temp_dir)
+    end
+
+    @test isfile(file_path)
+    @test isarchive(file_path)
+    @test basename(file_path) != basename(tzdata_url("latest"))
+
+    last_modified = mtime(file_path)
+    last_file_path = file_path
+
+    # No need to ignore output as this should never trigger a download
+    file_path = tzdata_download("latest", temp_dir)
+
+    @test file_path == last_file_path
+    @test mtime(file_path) == last_modified
+end