Overhaul printing of types (#194)

* Overhaul printing of types

Related to these Dates stdlib changes:

- JuliaLang/julia#30200
- JuliaLang/julia#30817

* Review comments

src/discovery.jl

@@ -243,7 +243,7 @@ function show_next_transition(io::IO, zdt::ZonedDateTime)
 
     println(io, "Transition Date:   ", Dates.format(instant, dateformat"yyyy-mm-dd"))
     println(io, "Local Time Change: ", time_format(instant), " → ", time_format(to), " (", direction, ")")
-    println(io, "Offset Change:     ", repr(from.zone.offset), " → ", repr(to.zone.offset))
+    println(io, "Offset Change:     ", repr("text/plain", from.zone.offset), " → ", repr("text/plain", to.zone.offset))
     println(io, "Transition From:   ", zdt_format(from))
     println(io, "Transition To:     ", zdt_format(to))
 

src/io.jl

@@ -1,20 +1,8 @@
 using Dates: value
 
-Base.print(io::IO, tz::TimeZone) = print(io, tz.name)
 function Base.print(io::IO, tz::FixedTimeZone)
-    isempty(tz.name) ? print(io, "UTC", tz.offset) : print(io, tz.name)
-end
-Base.print(io::IO, zdt::ZonedDateTime) = print(io, localtime(zdt), zdt.zone.offset)
-
-function Base.show(io::IO, t::Transition)
-    print(io, t.utc_datetime, " ")
-    show(io, t.zone.offset)
-    !isempty(t.zone.name) && print(io, " (", t.zone.name, ")")
-end
-
-function Base.show(io::IO, tz::FixedTimeZone)
-    if get(io, :compact, false)
-        print(io, tz)
+    if get(io, :compact, true)
+        isempty(tz.name) ? print(io, "UTC", tz.offset) : print(io, tz.name)
     else
         offset_str = "UTC" * offset_string(tz.offset, true)  # Use ISO 8601 for comparision
         if isempty(tz.name)
@@ -27,9 +15,9 @@ function Base.show(io::IO, tz::FixedTimeZone)
     end
 end
 
-function Base.show(io::IO, tz::VariableTimeZone)
-    if get(io, :compact, false)
-        print(io, tz)
+function Base.print(io::IO, tz::VariableTimeZone)
+    if get(io, :compact, true)
+        print(io, tz.name)
     else
         trans = tz.transitions
 
@@ -56,4 +44,86 @@ function Base.show(io::IO, tz::VariableTimeZone)
     end
 end
 
-Base.show(io::IO,dt::ZonedDateTime) = print(io, string(dt))
+function Base.print(io::IO, t::Transition)
+    print(io, t.utc_datetime, " ")
+    show(io, MIME("text/plain"), t.zone.offset)  # Long-form
+    !isempty(t.zone.name) && print(io, " (", t.zone.name, ")")
+end
+
+Base.print(io::IO, zdt::ZonedDateTime) = print(io, localtime(zdt), zdt.zone.offset)
+
+
+function Base.show(io::IO, tz::FixedTimeZone)
+    if istimezone(tz.name, Class(:ALL)) && isequal(tz, TimeZone(tz.name, Class(:ALL)))
+        print(io, "tz\"$(tz.name)\"")
+    else
+        std = Dates.value(tz.offset.std)
+        dst = Dates.value(tz.offset.dst)
+
+        params = [repr(tz.name), repr(std)]
+        dst != 0 && push!(params, repr(dst))
+        print(io, FixedTimeZone, "(", join(params, ", "), ")")
+    end
+end
+
+function Base.show(io::IO, tz::VariableTimeZone)
+    # Compat printing when the time zone can be constructed with `@tz_str`
+    if istimezone(tz.name, Class(:ALL)) && isequal(tz, TimeZone(tz.name, Class(:ALL)))
+        print(io, "tz\"$(tz.name)\"")
+
+    # Compact printing of a custom time zone which is non-constructable
+    elseif get(io, :compact, false)
+        print(io, VariableTimeZone, "(")
+        show(io, tz.name)
+        print(io, ", ...)")
+
+    # Verbose printing which should print a fully constructable `VariableTimeZone`.
+    else
+        # Force `:compact => false` to make the force the transition vector printing into
+        # long form.
+        print(io, VariableTimeZone, "(")
+        show(io, tz.name)
+        print(io, ", ")
+        show(IOContext(io, :compact => false), tz.transitions)
+        print(io, ", ")
+        show(io, tz.cutoff)
+        print(io, ")")
+    end
+end
+
+function Base.show(io::IO, t::Transition)
+    # Note: Using combo of `:typeinfo` and `:limit` as a way of detecting when a vector of
+    # transitions is being printed in the REPL.
+    if get(io, :compact, false) || get(io, :typeinfo, Union{}) == Transition && get(io, :limit, false)
+        print(io, t)
+    else
+        # Fallback to calling the default show instead of reimplementing it.
+        invoke(show, Tuple{IO, Any}, io, t)
+    end
+end
+
+function Base.show(io::IO, zdt::ZonedDateTime)
+    if get(io, :compact, false)
+        print(io, zdt)
+    else
+        values = [
+            yearmonthday(zdt)...
+            hour(zdt)
+            minute(zdt)
+            second(zdt)
+            millisecond(zdt)
+        ]
+        index = something(findlast(!iszero, values), 1)
+        params = [
+            map(repr, values[1:index]);
+            repr(timezone(zdt); context=:compact => true)
+        ]
+
+        print(io, ZonedDateTime, "(", join(params, ", "), ")")
+    end
+end
+
+
+Base.show(io::IO, ::MIME"text/plain", t::Transition) = print(io, t)
+Base.show(io::IO, ::MIME"text/plain", tz::TimeZone) = print(IOContext(io, :compact => false), tz)
+Base.show(io::IO, ::MIME"text/plain", zdt::ZonedDateTime) = print(io, zdt)

src/utcoffset.jl

@@ -57,8 +57,18 @@ function offset_string(offset::UTCOffset, iso8601::Bool=false)
 end
 
 Base.print(io::IO, o::UTCOffset) = print(io, offset_string(o, true))
+
 function Base.show(io::IO, o::UTCOffset)
-    # Show DST as a separate offset since we want to distinguish between normal hourly
-    # daylight saving time offsets and exotic DST offsets (e.g. midsummer time).
-    print(io, "UTC", offset_string(o.std), "/", offset_string(o.dst))
+    if get(io, :compact, false)
+        # Show DST as a separate offset since we want to distinguish between normal hourly
+        # daylight saving time offsets and exotic DST offsets (e.g. midsummer time).
+        print(io, "UTC", offset_string(o.std), "/", offset_string(o.dst))
+    else
+        # Fallback to calling the default show instead of reimplementing it.
+        invoke(show, Tuple{IO, Any}, io, o)
+    end
+end
+
+function Base.show(io::IO, ::MIME"text/plain", o::UTCOffset)
+    show(IOContext(io, :compact => true), o)
 end

test/helpers.jl

@@ -28,3 +28,14 @@ function ignore_output(body::Function; stdout::Bool=true, stderr::Bool=true)
 
     return result
 end
+
+# Used in tests as a shorter form of: `sprint(show, ..., context=:compact => true)`
+show_compact = (io, args...) -> show(IOContext(io, :compact => true), args...)
+
+# Takes the tuple from `compile` and adds the result into TimeZones cache. Typically should
+# not be used and only should be required if the test tzdata version and built tzdata
+# version do not match.
+function cache_tz((tz, class)::Tuple{TimeZone, TimeZones.Class})
+    TimeZones.TIME_ZONE_CACHE[TimeZones.name(tz)] = (tz, class)
+    return tz
+end

test/io.jl

@@ -1,52 +1,76 @@
 using TimeZones.TZData: parse_components
+using TimeZones: Transition
 
+dt = DateTime(1942,12,25,1,23,45)
+custom_dt = DateTime(1800,1,1)
+
+utc = FixedTimeZone("UTC")
+gmt = FixedTimeZone("GMT", 0)
+foo = FixedTimeZone("FOO", 0)
 null = FixedTimeZone("", 10800)
 fixed = FixedTimeZone("UTC+01:00")
 est = FixedTimeZone("EST", -18000)
 warsaw = first(compile("Europe/Warsaw", tzdata["europe"]))
-apia = first(compile("Pacific/Apia", tzdata["australasia"]))
-honolulu = first(compile("Pacific/Honolulu", tzdata["northamerica"]))  # Uses cutoff
+apia = cache_tz(compile("Pacific/Apia", tzdata["australasia"]))
+honolulu = cache_tz(compile("Pacific/Honolulu", tzdata["northamerica"]))  # Uses cutoff
 ulyanovsk = first(compile("Europe/Ulyanovsk", tzdata["europe"]))  # No named abbreviations
 new_york = first(compile("America/New_York", tzdata["northamerica"]))  # Underscore in name
-dt = DateTime(1942,12,25,1,23,45)
-
-# TimeZones as a string
-@test string(null) == "UTC+03:00"
-@test string(fixed) == "UTC+01:00"
-@test string(est) == "EST"
-@test string(warsaw) == "Europe/Warsaw"
-@test string(apia) == "Pacific/Apia"
-@test string(honolulu) == "Pacific/Honolulu"
-@test string(ulyanovsk) == "Europe/Ulyanovsk"
-
-# Alternatively in Julia 0.7.0-DEV.4517 we could use
-# `sprint(show, ..., context=:compact => true)`
-show_compact = (io, args...) -> show(IOContext(io, :compact => true), args...)
-@test sprint(show_compact, null) == "UTC+03:00"
-@test sprint(show_compact, fixed) == "UTC+01:00"
-@test sprint(show_compact, est) == "EST"
-@test sprint(show_compact, warsaw) == "Europe/Warsaw"
-@test sprint(show_compact, apia) == "Pacific/Apia"
-@test sprint(show_compact, honolulu) == "Pacific/Honolulu"
-@test sprint(show_compact, ulyanovsk) == "Europe/Ulyanovsk"
-
-@test sprint(show, null) == "UTC+03:00"
-@test sprint(show, fixed) == "UTC+01:00"
-@test sprint(show, est) == "EST (UTC-5)"
-@test sprint(show, warsaw) == "Europe/Warsaw (UTC+1/UTC+2)"
-@test sprint(show, apia) == "Pacific/Apia (UTC+13/UTC+14)"
-@test sprint(show, honolulu) == "Pacific/Honolulu (UTC-10)"
-@test sprint(show, ulyanovsk) == "Europe/Ulyanovsk (UTC+4)"
-
-# UTC and GMT are special cases
-@test sprint(show, FixedTimeZone("UTC")) == "UTC"
-@test sprint(show, FixedTimeZone("GMT", 0)) == "GMT"
-@test sprint(show, FixedTimeZone("FOO", 0)) == "FOO (UTC+0)"
+custom = VariableTimeZone("Test/Custom", [Transition(custom_dt, utc)])  # Non-cached variable time zone
+
+@test sprint(print, utc) == "UTC"
+@test sprint(print, gmt) == "GMT"
+@test sprint(print, foo) == "FOO"
+@test sprint(print, null) == "UTC+03:00"
+@test sprint(print, fixed) == "UTC+01:00"
+@test sprint(print, est) == "EST"
+@test sprint(print, warsaw) == "Europe/Warsaw"
+@test sprint(print, apia) == "Pacific/Apia"
+@test sprint(print, honolulu) == "Pacific/Honolulu"
+@test sprint(print, ulyanovsk) == "Europe/Ulyanovsk"
+@test sprint(print, custom) == "Test/Custom"
+
+@test sprint(show_compact, utc) == "tz\"UTC\""
+@test sprint(show_compact, gmt) == "tz\"GMT\""
+@test sprint(show_compact, foo) == "FixedTimeZone(\"FOO\", 0)"
+@test sprint(show_compact, null) == "FixedTimeZone(\"\", 10800)"
+@test sprint(show_compact, fixed) == "tz\"UTC+01:00\""
+@test sprint(show_compact, est) == "tz\"EST\""
+@test sprint(show_compact, warsaw) == "tz\"Europe/Warsaw\""
+@test sprint(show_compact, apia) == "tz\"Pacific/Apia\""
+@test sprint(show_compact, honolulu) == "tz\"Pacific/Honolulu\""
+@test sprint(show_compact, ulyanovsk) == "tz\"Europe/Ulyanovsk\""
+@test sprint(show_compact, custom) == "VariableTimeZone(\"Test/Custom\", ...)"
+
+@test sprint(show, utc) == "tz\"UTC\""
+@test sprint(show, gmt) == "tz\"GMT\""
+@test sprint(show, foo) == "FixedTimeZone(\"FOO\", 0)"
+@test sprint(show, null) == "FixedTimeZone(\"\", 10800)"
+@test sprint(show, fixed) == "tz\"UTC+01:00\""
+@test sprint(show, est) == "tz\"EST\""
+@test sprint(show, warsaw) == "tz\"Europe/Warsaw\""
+@test sprint(show, apia) == "tz\"Pacific/Apia\""
+@test sprint(show, honolulu) == "tz\"Pacific/Honolulu\""
+@test sprint(show, ulyanovsk) == "tz\"Europe/Ulyanovsk\""
+@test sprint(show, custom) == "VariableTimeZone(\"Test/Custom\", Transition[Transition($(repr(custom_dt)), tz\"UTC\")], nothing)"
+
+@test sprint(show, MIME("text/plain"), utc) == "UTC"
+@test sprint(show, MIME("text/plain"), gmt) == "GMT"
+@test sprint(show, MIME("text/plain"), foo) == "FOO (UTC+0)"
+@test sprint(show, MIME("text/plain"), null) == "UTC+03:00"
+@test sprint(show, MIME("text/plain"), fixed) == "UTC+01:00"
+@test sprint(show, MIME("text/plain"), est) == "EST (UTC-5)"
+@test sprint(show, MIME("text/plain"), warsaw) == "Europe/Warsaw (UTC+1/UTC+2)"
+@test sprint(show, MIME("text/plain"), apia) == "Pacific/Apia (UTC+13/UTC+14)"
+@test sprint(show, MIME("text/plain"), honolulu) == "Pacific/Honolulu (UTC-10)"
+@test sprint(show, MIME("text/plain"), ulyanovsk) == "Europe/Ulyanovsk (UTC+4)"
+@test sprint(show, MIME("text/plain"), custom) == "Test/Custom (UTC+0)"
 
 # ZonedDateTime as a string
 zdt = ZonedDateTime(dt, warsaw)
 @test string(zdt) == "1942-12-25T01:23:45+01:00"
-@test sprint(show, zdt) == "1942-12-25T01:23:45+01:00"
+@test sprint(show_compact, zdt) == "1942-12-25T01:23:45+01:00"
+@test sprint(show, zdt) == "ZonedDateTime(1942, 12, 25, 1, 23, 45, tz\"Europe/Warsaw\")"
+@test sprint(show, MIME("text/plain"), zdt) == "1942-12-25T01:23:45+01:00"
 
 
 # TimeZone parsing
@@ -105,3 +129,38 @@ f = "yyyy/m/d H:M:S zzz"
 df = Dates.DateFormat("yyyy-mm-ddTHH:MM:SS ZZZ")
 zdt = ZonedDateTime(dt, warsaw)
 @test_throws ArgumentError parse(ZonedDateTime, Dates.format(zdt, df), df)
+
+
+# Displaying VariableTimeZone's vector of transitions on the REPL has a special printing
+@testset "Transitions I/O" begin
+    transitions = honolulu.transitions  # Only contains a few transitions
+    t = transitions[2]  # 1896-01-13T22:31:26 UTC-10:30/+0 (HST)
+
+    @testset "basic" begin
+        @test sprint(print, t) == "1896-01-13T22:31:26 UTC-10:30/+0 (HST)"
+        @test sprint(show_compact, t) == "1896-01-13T22:31:26 UTC-10:30/+0 (HST)"
+        @test sprint(show, t) == "Transition($(repr(t.utc_datetime)), FixedTimeZone(\"HST\", -37800))"
+        @test sprint(show, MIME("text/plain"), t) == "1896-01-13T22:31:26 UTC-10:30/+0 (HST)"
+    end
+
+    @testset "REPL vector" begin
+        expected_full = string(
+            TimeZones.Transition,
+            "[",
+            join(map(t -> sprint(show, t, context=:compact => false), transitions), ", "),
+            "]",
+        )
+
+        # Note: The output here is different from the interactive REPL but is representative
+        # of the output.
+        expected_repl = string(
+            TimeZones.Transition,
+            "[",
+            join(map(t -> sprint(show, t, context=:compact => true), transitions), ", "),
+            "]",
+        )
+
+        @test sprint(show, transitions, context=:compact => false) == expected_full
+        @test sprint(show, transitions; context=:limit => true) == expected_repl
+    end
+end

test/utcoffset.jl

@@ -42,5 +42,17 @@ let a = UTCOffset(7200, 3600), b = UTCOffset(3600, 7200)
     @test isequal(a, b)
 end
 
-@test sprint(show, UTCOffset(0, 0)) == "UTC+0/+0"
-@test sprint(show, UTCOffset(3600, 7200)) == "UTC+1/+2"
+@test sprint(show_compact, UTCOffset(0, 0)) == "UTC+0/+0"
+@test sprint(show_compact, UTCOffset(3600, 7200)) == "UTC+1/+2"
+
+# https://github.com/JuliaLang/julia/pull/30817
+if VERSION >= v"1.2.0-DEV.223"
+    @test sprint(show, UTCOffset(0, 0)) == "UTCOffset(Second(0), Second(0))"
+    @test sprint(show, UTCOffset(3600, 7200)) == "UTCOffset(Second(3600), Second(7200))"
+else
+    @test sprint(show, UTCOffset(0, 0)) == "UTCOffset(0 seconds, 0 seconds)"
+    @test sprint(show, UTCOffset(3600, 7200)) == "UTCOffset(3600 seconds, 7200 seconds)"
+end
+
+@test sprint(show, MIME("text/plain"), UTCOffset(0, 0)) == "UTC+0/+0"
+@test sprint(show, MIME("text/plain"), UTCOffset(3600, 7200)) == "UTC+1/+2"