simpler fallback behavior

[nicksnyder]

Fixes #182

name                                                                                        old time/op    new time/op    delta
Localizer_Localize/missing_translation_from_default_language_with_other_translation-8         34.4µs ± 1%     0.3µs ± 6%   -99.11%  (p=0.000 n=8+8)
Localizer_Localize/missing_translation_not_default_language_with_other_translation-8          35.5µs ± 3%     0.4µs ± 9%   -99.00%  (p=0.000 n=8+8)
Localizer_Localize/empty_translation_without_fallback-8                                       32.4µs ± 1%     0.4µs ± 4%   -98.83%  (p=0.001 n=7+7)
Localizer_Localize/message_id_not_mismatched-8                                                 305ns ±22%     279ns ± 4%    -8.45%  (p=0.040 n=8+8)
Localizer_Localize/template_data,_plural_count_float,_default_message-8                       13.1µs ±15%    12.1µs ± 3%    -7.90%  (p=0.002 n=8+8)
Localizer_Localize/template_data,_custom_delims,_default_message-8                            9.21µs ± 2%    8.51µs ± 1%    -7.65%  (p=0.000 n=7+8)
Localizer_Localize/accept_not_default_language,_other_message_in_bundle,_default_message-8     227ns ± 4%     214ns ± 5%    -5.94%  (p=0.001 n=8+8)
Localizer_Localize/template_data,_plural_count_other,_default_message-8                       12.2µs ± 5%    11.5µs ± 1%    -5.84%  (p=0.000 n=7+8)
Localizer_Localize/accept_not_default_language,_message_in_bundle-8                            295ns ± 3%     278ns ± 4%    -5.51%  (p=0.000 n=8+7)
Localizer_Localize/template_data,_plural_count_one,_default_message-8                         12.3µs ± 4%    11.7µs ± 6%    -4.17%  (p=0.029 n=7+8)
Localizer_Localize/template_data,_custom_delims,_bundle_message-8                              821ns ± 3%     795ns ± 5%    -3.13%  (p=0.017 n=7+7)
Localizer_Localize/fallback_to_non-default_less_specific_language-8                            766ns ± 2%     753ns ± 3%    -1.71%  (p=0.036 n=8+8)
Localizer_Localize/missing_translation_from_default_language-8                                 283ns ±11%     285ns ± 2%      ~     (p=0.692 n=8+7)
Localizer_Localize/accept_default_language,_message_in_bundle-8                                278ns ± 2%     278ns ± 5%      ~     (p=0.733 n=8+8)
Localizer_Localize/accept_default_language,_message_in_bundle,_default_message-8               288ns ± 2%     282ns ± 5%      ~     (p=0.164 n=8+8)
Localizer_Localize/accept_not_default_language,_message_in_bundle,_default_message-8           295ns ± 2%     291ns ± 4%      ~     (p=0.524 n=8+8)
Localizer_Localize/accept_default_language,_default_message-8                                  531ns ± 5%     539ns ± 5%      ~     (p=0.320 n=7+8)
Localizer_Localize/accept_not_default_language,_default_message-8                              452ns ± 4%     446ns ± 3%      ~     (p=0.101 n=7+7)
Localizer_Localize/fallback_to_non-default_more_specific_language-8                            291ns ± 3%     284ns ±10%      ~     (p=0.061 n=8+8)
Localizer_Localize/plural_count_one,_bundle_message-8                                         1.12µs ± 3%    1.14µs ±14%      ~     (p=0.842 n=7+8)
Localizer_Localize/plural_count_other,_bundle_message-8                                       1.11µs ± 3%    1.17µs ±12%      ~     (p=0.224 n=8+8)
Localizer_Localize/plural_count_float,_bundle_message-8                                       1.33µs ±13%    1.33µs ± 5%      ~     (p=0.574 n=8+8)
Localizer_Localize/plural_count_one,_default_message-8                                        9.10µs ± 8%   10.86µs ±53%      ~     (p=0.574 n=8+8)
Localizer_Localize/plural_count_missing_other,_default_message-8                               818ns ± 3%     837ns ± 9%      ~     (p=0.243 n=8+7)
Localizer_Localize/plural_count_other,_default_message-8                                      10.1µs ±14%     9.9µs ±16%      ~     (p=0.721 n=8+8)
Localizer_Localize/plural_count_float,_default_message-8                                      10.7µs ±24%     9.5µs ± 4%      ~     (p=0.281 n=8+7)
Localizer_Localize/template_data,_bundle_message-8                                             831ns ± 5%     888ns ±19%      ~     (p=0.458 n=8+8)
Localizer_Localize/template_data,_default_message-8                                           9.04µs ± 3%    8.82µs ± 7%      ~     (p=0.189 n=7+8)
Localizer_Localize/template_data,_plural_count_one,_bundle_message-8                          1.28µs ± 4%    1.26µs ± 2%      ~     (p=0.155 n=7+7)
Localizer_Localize/template_data,_plural_count_float,_bundle_message-8                        1.47µs ± 3%    1.48µs ± 6%      ~     (p=0.777 n=8+8)
Localizer_Localize/template_data,_plural_count_other,_bundle_message-8                        1.27µs ± 4%    1.31µs ± 5%    +3.64%  (p=0.047 n=8+8)
Localizer_Localize/message_id_mismatch-8                                                      38.0ns ± 1%    40.0ns ± 4%    +5.30%  (p=0.000 n=7+8)
Localizer_Localize/plural_count_missing_one,_default_message-8                                9.33µs ± 8%   10.81µs ±17%   +15.94%  (p=0.009 n=8+7)
Localizer_Localize/missing_translation_from_not_default_language-8                             206ns ± 3%     340ns ± 6%   +64.93%  (p=0.000 n=8+8)

name                                                                                        old alloc/op   new alloc/op   delta
Localizer_Localize/missing_translation_not_default_language_with_other_translation-8          10.0kB ± 0%     0.0kB ± 0%   -99.52%  (p=0.000 n=8+8)
Localizer_Localize/missing_translation_from_default_language_with_other_translation-8         9.42kB ± 0%    0.05kB ± 0%   -99.49%  (p=0.000 n=8+8)
Localizer_Localize/empty_translation_without_fallback-8                                       8.83kB ± 0%    0.05kB ± 0%   -99.46%  (p=0.002 n=7+8)
Localizer_Localize/message_id_mismatch-8                                                       32.0B ± 0%     32.0B ± 0%      ~     (all equal)
Localizer_Localize/message_id_not_mismatched-8                                                 0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_default_language,_message_in_bundle-8                                0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_default_language,_message_in_bundle,_default_message-8               0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_not_default_language,_message_in_bundle-8                            0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_not_default_language,_other_message_in_bundle,_default_message-8     0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_not_default_language,_message_in_bundle,_default_message-8           0.00B          0.00B           ~     (all equal)
Localizer_Localize/accept_default_language,_default_message-8                                   368B ± 0%      368B ± 0%      ~     (all equal)
Localizer_Localize/accept_not_default_language,_default_message-8                               368B ± 0%      368B ± 0%      ~     (all equal)
Localizer_Localize/fallback_to_non-default_less_specific_language-8                            56.0B ± 0%     56.0B ± 0%      ~     (all equal)
Localizer_Localize/fallback_to_non-default_more_specific_language-8                            0.00B          0.00B           ~     (all equal)
Localizer_Localize/plural_count_one,_bundle_message-8                                           592B ± 0%      592B ± 0%      ~     (all equal)
Localizer_Localize/plural_count_other,_bundle_message-8                                         592B ± 0%      592B ± 0%      ~     (all equal)
Localizer_Localize/plural_count_float,_bundle_message-8                                         624B ± 0%      624B ± 0%      ~     (all equal)
Localizer_Localize/plural_count_one,_default_message-8                                        5.06kB ± 0%    5.06kB ± 0%      ~     (p=0.298 n=7+8)
Localizer_Localize/plural_count_missing_one,_default_message-8                                5.00kB ± 0%    5.00kB ± 0%      ~     (p=0.324 n=7+8)
Localizer_Localize/plural_count_missing_other,_default_message-8                                784B ± 0%      784B ± 0%      ~     (all equal)
Localizer_Localize/plural_count_other,_default_message-8                                      5.06kB ± 0%    5.06kB ± 0%      ~     (p=0.572 n=8+7)
Localizer_Localize/plural_count_float,_default_message-8                                      5.10kB ± 0%    5.09kB ± 0%      ~     (p=0.529 n=8+6)
Localizer_Localize/template_data,_bundle_message-8                                              208B ± 0%      208B ± 0%      ~     (all equal)
Localizer_Localize/template_data,_default_message-8                                           4.46kB ± 0%    4.46kB ± 0%      ~     (p=1.000 n=8+8)
Localizer_Localize/template_data,_custom_delims,_bundle_message-8                               208B ± 0%      208B ± 0%      ~     (all equal)
Localizer_Localize/template_data,_custom_delims,_default_message-8                            4.46kB ± 0%    4.46kB ± 0%      ~     (p=0.075 n=8+8)
Localizer_Localize/template_data,_plural_count_one,_bundle_message-8                            288B ± 0%      288B ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_other,_bundle_message-8                          288B ± 0%      288B ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_float,_bundle_message-8                          336B ± 0%      336B ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_one,_default_message-8                         5.03kB ± 0%    5.03kB ± 0%      ~     (p=1.000 n=8+8)
Localizer_Localize/template_data,_plural_count_other,_default_message-8                       5.03kB ± 0%    5.03kB ± 0%      ~     (p=0.886 n=8+8)
Localizer_Localize/template_data,_plural_count_float,_default_message-8                       5.08kB ± 0%    5.08kB ± 0%      ~     (p=1.000 n=8+8)
Localizer_Localize/missing_translation_from_default_language-8                                 16.0B ± 0%     48.0B ± 0%  +200.00%  (p=0.000 n=8+8)
Localizer_Localize/missing_translation_from_not_default_language-8                             16.0B ± 0%     48.0B ± 0%  +200.00%  (p=0.000 n=8+8)

name                                                                                        old allocs/op  new allocs/op  delta
Localizer_Localize/missing_translation_not_default_language_with_other_translation-8             229 ± 0%         1 ± 0%   -99.56%  (p=0.000 n=8+8)
Localizer_Localize/missing_translation_from_default_language_with_other_translation-8            208 ± 0%         1 ± 0%   -99.52%  (p=0.000 n=8+8)
Localizer_Localize/empty_translation_without_fallback-8                                          188 ± 0%         1 ± 0%   -99.47%  (p=0.000 n=8+8)
Localizer_Localize/message_id_mismatch-8                                                        1.00 ± 0%      1.00 ± 0%      ~     (all equal)
Localizer_Localize/message_id_not_mismatched-8                                                  0.00           0.00           ~     (all equal)
Localizer_Localize/missing_translation_from_default_language-8                                  1.00 ± 0%      1.00 ± 0%      ~     (all equal)
Localizer_Localize/missing_translation_from_not_default_language-8                              1.00 ± 0%      1.00 ± 0%      ~     (all equal)
Localizer_Localize/accept_default_language,_message_in_bundle-8                                 0.00           0.00           ~     (all equal)
Localizer_Localize/accept_default_language,_message_in_bundle,_default_message-8                0.00           0.00           ~     (all equal)
Localizer_Localize/accept_not_default_language,_message_in_bundle-8                             0.00           0.00           ~     (all equal)
Localizer_Localize/accept_not_default_language,_other_message_in_bundle,_default_message-8      0.00           0.00           ~     (all equal)
Localizer_Localize/accept_not_default_language,_message_in_bundle,_default_message-8            0.00           0.00           ~     (all equal)
Localizer_Localize/accept_default_language,_default_message-8                                   4.00 ± 0%      4.00 ± 0%      ~     (all equal)
Localizer_Localize/accept_not_default_language,_default_message-8                               4.00 ± 0%      4.00 ± 0%      ~     (all equal)
Localizer_Localize/fallback_to_non-default_less_specific_language-8                             4.00 ± 0%      4.00 ± 0%      ~     (all equal)
Localizer_Localize/fallback_to_non-default_more_specific_language-8                             0.00           0.00           ~     (all equal)
Localizer_Localize/plural_count_one,_bundle_message-8                                           9.00 ± 0%      9.00 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_other,_bundle_message-8                                         9.00 ± 0%      9.00 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_float,_bundle_message-8                                         10.0 ± 0%      10.0 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_one,_default_message-8                                          47.0 ± 0%      47.0 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_missing_one,_default_message-8                                  47.0 ± 0%      47.0 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_missing_other,_default_message-8                                8.00 ± 0%      8.00 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_other,_default_message-8                                        47.0 ± 0%      47.0 ± 0%      ~     (all equal)
Localizer_Localize/plural_count_float,_default_message-8                                        48.0 ± 0%      48.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_bundle_message-8                                              6.00 ± 0%      6.00 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_default_message-8                                             40.0 ± 0%      40.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_custom_delims,_bundle_message-8                               6.00 ± 0%      6.00 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_custom_delims,_default_message-8                              40.0 ± 0%      40.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_one,_bundle_message-8                            9.00 ± 0%      9.00 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_other,_bundle_message-8                          9.00 ± 0%      9.00 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_float,_bundle_message-8                          10.0 ± 0%      10.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_one,_default_message-8                           54.0 ± 0%      54.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_other,_default_message-8                         54.0 ± 0%      54.0 ± 0%      ~     (all equal)
Localizer_Localize/template_data,_plural_count_float,_default_message-8                         55.0 ± 0%      55.0 ± 0%      ~     (all equal)

[codecov]

Codecov Report

Merging #189 into master will increase coverage by 0.69%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #189      +/-   ##
==========================================
+ Coverage   82.01%   82.70%   +0.69%     
==========================================
  Files          14       14              
  Lines        1173     1168       -5     
==========================================
+ Hits          962      966       +4     
+ Misses        147      141       -6     
+ Partials       64       61       -3     

Impacted Files	Coverage Δ
v2/i18n/bundle.go	61.36% <100.00%> (+3.86%)	⬆️
v2/i18n/localizer.go	92.64% <100.00%> (+10.82%)	⬆️

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[artch]

What is the ETA on this? This issue blocks Hugo project from taking advantage of the v2 new features.

[nicksnyder]

I don't have an ETA for this. See #201.

I think this PR is a good change, but I didn't have a chance to write as many unit tests as I wanted and I have lost all context on this.

One option for Hugo, at least for development and testing, is to depend on this branch directly to see if everything works as you expect.