EN/Time: Add "<integer> <day-of-time> from <time>" rule

Summary:
"What is the date three Fridays from now?" resolves incorrectly:

- On Friday, it detects "three fridays", "fridays from now"
- On other days, it detects "three fridays", "from now"

Thus, added a new rule, "<integer> <day-of-week> from <time>" to give the expected result of three Fridays after the current day and added test examples. If there are too many test examples, please let me know!

Reviewed By: chinmay87

Differential Revision: D15110770

fbshipit-source-id: a77b86de8b6d8f7c947df9e14edb17f61bcc8419

Duckling/Time/EN/Corpus.hs

@@ -13,15 +13,17 @@ module Duckling.Time.EN.Corpus
   , defaultCorpus
   , negativeCorpus
   , latentCorpus
+  , diffCorpus
   ) where
 
 import Data.String
 import Prelude
 
+import Duckling.Core
 import Duckling.Resolve
 import Duckling.Testing.Types hiding (examples)
 import Duckling.Time.Corpus
-import Duckling.Time.Types hiding (Month)
+import Duckling.Time.Types hiding (Month, refTime)
 import Duckling.TimeGrain.Types hiding (add)
 
 corpus :: Corpus
@@ -153,6 +155,21 @@ latentCorpus = (testContext, testOptions {withLatent = True}, xs)
                  ]
       ]
 
+diffContext :: Context
+diffContext = Context
+  { locale = makeLocale EN Nothing
+  , referenceTime = refTime (2013, 2, 15, 4, 30, 0) (-2)
+  }
+
+diffCorpus :: Corpus
+diffCorpus = (diffContext, testOptions, diffExamples)
+  where
+    diffExamples =
+      examples (datetime (2013, 3, 8, 0, 0, 0) Day)
+               [ "3 fridays from now"
+               , "three fridays from now"
+               ]
+
 allExamples :: [Example]
 allExamples = concat
   [ examples (datetime (2013, 2, 12, 4, 30, 0) Second)
@@ -614,6 +631,18 @@ allExamples = concat
   , examples (datetime (2016, 2, 12, 0, 0, 0) Day)
              [ "3 years from today"
              ]
+  , examples (datetime (2013, 3, 1, 0, 0, 0) Day)
+             [ "3 fridays from now"
+             , "three fridays from now"
+             ]
+  , examples (datetime (2013, 2, 24, 0, 0, 0) Day)
+             [ "2 sundays from now"
+             , "two sundays from now"
+             ]
+  , examples (datetime (2013, 3, 12, 0, 0, 0) Day)
+             [ "4 tuesdays from now"
+             , "four tuesdays from now"
+             ]
   , examples (datetime (2013, 2, 19, 4, 0, 0) Hour)
              [ "in 7 days"
              ]

Duckling/Time/EN/Rules.hs

@@ -322,6 +322,22 @@ ruleTheNthTimeAfterTime = Rule
       _ -> Nothing
   }
 
+ruleNDOWFromTime :: Rule
+ruleNDOWFromTime = Rule
+  { name = "<integer> <day-of-week> from <time>"
+  , pattern =
+    [ dimension Numeral
+    , Predicate isADayOfWeek
+    , regex "from"
+    , dimension Time
+    ]
+  , prod = \tokens -> case tokens of
+      (token:Token Time td1:_:Token Time td2:_) -> do
+        n <- getIntValue token
+        tt $ predNthAfter (n - 1) td1 td2
+      _ -> Nothing
+  }
+
 ruleYearLatent :: Rule
 ruleYearLatent = Rule
   { name = "year (latent)"
@@ -2392,6 +2408,7 @@ rules =
   , ruleTheNthTimeOfTime
   , ruleNthTimeAfterTime
   , ruleTheNthTimeAfterTime
+  , ruleNDOWFromTime
   , ruleYearLatent
   , ruleYearADBC
   , ruleTheDOMNumeral

tests/Duckling/Time/EN/Tests.hs

@@ -47,6 +47,7 @@ tests :: TestTree
 tests = testGroup "EN Tests"
   [ makeCorpusTest [This Time] defaultCorpus
   , makeNegativeCorpusTest [This Time] negativeCorpus
+  , makeCorpusTest [This Time] diffCorpus
   , exactSecondTests
   , valuesTest
   , intersectTests