Add dlint rule to suggest === (#10485)

* Add dlint rule to suggest ===

This rule doesn’t quite work in all cases since you can have types
that have Eq instances but not Show instances. However, I think the
benefits of people learning about this are much larger than the
downsides here of getting a hint that doesn’t apply in edge cases.

changelog_begin
changelog_end

* fix all the tests, why are there so many :(

changelog_begin
changelog_end

compiler/damlc/daml-ide-core/dlint.yaml

@@ -612,6 +612,11 @@
     - warn: {lhs: null x  , rhs: "False", side: isTuple x, name: Using null on tuple}
     - warn: {lhs: length x, rhs: "1"    , side: isTuple x, name: Using length on tuple}
 
+    # ASSERTIONS
+
+    - warn: {lhs: "assert (x == y)", rhs: "x === y", name: Use === for better error messages}
+    - warn: {lhs: "assert (x /= y)", rhs: "x =/= y", name: Use === for better error messages}
+
 - group:
     name: generalise
     enabled: false

compiler/damlc/tests/daml-test-files/ActionFail.daml

@@ -1,10 +1,12 @@
 -- Copyright (c) 2020, Digital Asset (Switzerland) GmbH and/or its affiliates.
 -- All rights reserved.
 
--- @INFO range=9:22-9:39; Use catOptionals
+-- @INFO range=11:22-11:39; Use catOptionals
 
 module ActionFail where
 
+import DA.Assert
+
 catOptionalsComp : [Optional a] -> [a]
 catOptionalsComp l = [x | Some x <- l]
 
@@ -14,7 +16,5 @@ catOptionalsMonad l = do
   return x
 
 main = scenario do
-  alice <- getParty "alice"
-  submit alice do
-    assert $ catOptionalsComp [None,Some 1,Some 2] == [1,2]
-    assert $ catOptionalsMonad [None,Some 1,Some 2] == [1,2]
+  catOptionalsComp [None,Some 1,Some 2] === [1,2]
+  catOptionalsMonad [None,Some 1,Some 2] === [1,2]

compiler/damlc/tests/daml-test-files/AliasNonLocal.daml

@@ -5,8 +5,10 @@
 
 module AliasNonLocal where
 
+import DA.Assert
+
 data Coin = BTC | Other Text
-  deriving (Eq)
+  deriving (Eq, Show)
 
 btc = BTC
 
@@ -17,5 +19,5 @@ main = scenario do
   let btc2 = BTC
   let other1 = other
   let other2 = Other
-  assert (btc1 == btc2)
-  assert (other1 "ETH" == other2 "ETH")
+  btc1 === btc2
+  other1 "ETH" === other2 "ETH"

compiler/damlc/tests/daml-test-files/Assert.daml

@@ -0,0 +1,9 @@
+-- Copyright (c) 2020, Digital Asset (Switzerland) GmbH and/or its affiliates.
+-- All rights reserved.
+
+-- @INFO range=9:3-9:18; Use ===
+
+module Assert where
+
+test = scenario do
+  assert (1 == 1)

compiler/damlc/tests/daml-test-files/Choice_no_params_template.daml

@@ -3,6 +3,8 @@
 
 module Choice_no_params_template where
 
+import DA.Assert
+
 template Bond
   with
     issuer : Party
@@ -30,7 +32,7 @@ template Bond
         with otherCid : ContractId Bond
         do
           otherBond <- fetch otherCid
-          assert $ this == otherBond with amount
+          this === otherBond with amount
           archive otherCid
           create $ Bond with amount = amount + otherBond.amount, ..
 

compiler/damlc/tests/daml-test-files/DataTypes.daml

@@ -7,6 +7,8 @@
 
 module DataTypes where
 
+import DA.Assert
+
 data Rec = Rec with x: Int
 
 newtype RecNT = RecNT with x: Int
@@ -38,17 +40,17 @@ eval = \case
 
 
 main = scenario do
-  assert $ (Rec with x = 5).x == 5
+  (Rec with x = 5).x === 5
 
-  assert $ (RecNT with x = 7).x == 7
+  (RecNT with x = 7).x === 7
 
   assert $ case Unit of {Unit -> True}
 
-  assert $ untag (MkTag 3) == 3
+  untag (MkTag 3) === 3
 
-  assert $ untagNT (MkTagNT 11) == 11
+  untagNT (MkTagNT 11) === 11
 
-  assert $ eval Zero == 0
-  assert $ eval (Num1 13) == 13
-  assert $ eval (Num2 with x = 17) == 17
-  assert $ eval (Plus with x = 19; y = 23) == 42
+  eval Zero === 0
+  eval (Num1 13) === 13
+  eval (Num2 with x = 17) === 17
+  eval (Plus with x = 19; y = 23) === 42

compiler/damlc/tests/daml-test-files/DiscloseViaChoiceObserver.daml

@@ -3,8 +3,10 @@
 
 module DiscloseViaChoiceObserver where
 
+import DA.Assert
+
 -- @SINCE-LF 1.11
--- @WARN range=37:15-37:67; Use of divulged contracts is deprecated
+-- @WARN range=39:15-39:67; Use of divulged contracts is deprecated
 
 -- This example demonstrates the canonical use of choice-observers to achieve disclosure.
 
@@ -35,5 +37,5 @@ test = scenario do
     submit alice do exercise id DiscloseTo with receiver = bob
     -- (4) Now Bob can see the secret
     secret <- submit bob do exercise id Reveal with receiver = bob
-    assert (secret == "s3cr3t")
+    secret === "s3cr3t"
     pure ()

compiler/damlc/tests/daml-test-files/EqContractId.daml

@@ -4,6 +4,8 @@
 
 module EqContractId where
 
+import DA.Assert
+
 template Foo with
     p: Party
   where
@@ -13,5 +15,5 @@ main = scenario do
   alice <- getParty "Alice"
   cid1 <- submit alice do create Foo{p = alice}
   cid2 <- submit alice do create Foo{p = alice}
-  assert $ cid1 == cid1
-  assert $ cid1 /= cid2
+  cid1 === cid1
+  cid1 =/= cid2

compiler/damlc/tests/daml-test-files/Existential.daml

@@ -4,16 +4,17 @@
 {-# LANGUAGE ExistentialQuantification #-}
 
 -- @WARN Modules compiled with the ExistentialQuantification language extension might not work properly with data-dependencies.
--- @ ERROR range=15:1-15:7; Pattern match with existential type.
+-- @ ERROR range=17:1-17:7; Pattern match with existential type.
 
 
 module Existential where
 
+import DA.Assert
+
 data Foo = forall a . Foo (a, a -> Int)
 
 runFoo : Foo -> Int
 runFoo (Foo (a, b)) = b a
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert (runFoo (Foo (12, (+1))) == 13)
+    runFoo (Foo (12, (+1))) === 13

compiler/damlc/tests/daml-test-files/ExistentialSum.daml

@@ -4,11 +4,13 @@
 {-# LANGUAGE ExistentialQuantification #-}
 
 -- @WARN Modules compiled with the ExistentialQuantification language extension might not work properly with data-dependencies.
--- @ ERROR range=17:1-17:7; Pattern match with existential type.
+-- @ ERROR range=19:1-19:7; Pattern match with existential type.
 
 
 module ExistentialSum where
 
+import DA.Assert
+
 data Foo
   = Bar
   | forall a. Baz a
@@ -18,5 +20,4 @@ runFoo Bar = 0
 runFoo (Baz _) = 1
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert (runFoo (Baz "quux") == 1)
+    runFoo (Baz "quux") === 1

compiler/damlc/tests/daml-test-files/Fib.daml

@@ -4,11 +4,12 @@
 
 module Fib where
 
+import DA.Assert
+
 fib : Int -> Int
 fib 0 = 0
 fib 1 = 1
 fib n = fib (n-1) + fib (n-2)
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert (fib 10 == 55)
+  fib 10 === 55

compiler/damlc/tests/daml-test-files/IntBoundsDynamic.daml

@@ -5,6 +5,8 @@
 
 module IntBoundsDynamic where
 
+import DA.Assert
+
 maxInt : Int
 maxInt = 9223372036854775807
 
@@ -13,6 +15,6 @@ minInt = -9223372036854775808
 
 test = scenario do
     p <- getParty "p"
-    assert $ negate maxInt - 1 == minInt
+    negate maxInt - 1 === minInt
     submitMustFail p $ pure $ maxInt+1
     submitMustFail p $ pure $ minInt-1

compiler/damlc/tests/daml-test-files/Iou12.daml

@@ -4,6 +4,8 @@
 
 module Iou12 where
 
+import DA.Assert
+
 template Iou
   with
     issuer : Party
@@ -56,7 +58,7 @@ template Iou
           -- Merge two IOUs by aggregating their amounts.
           otherIou <- fetch otherCid
           -- Check the two IOU's are compatible
-          assert $ this == otherIou with amount
+          this === otherIou with amount
           -- Retire the old Iou by transferring to the
           -- issuer and archiving
           transferCid <-
@@ -109,7 +111,7 @@ main = scenario do
   -- Assert things are as they should be
   submit alice do
     aliceIou <- fetch rest
-    assert $ aliceIou == Iou with
+    aliceIou === Iou with
       issuer   = bank
       owner    = alice
       currency = "USD"
@@ -119,7 +121,7 @@ main = scenario do
 
   submit bob do
     bobIou <- fetch iouTotalCid
-    assert $ bobIou == Iou with
+    bobIou === Iou with
       issuer   = bank
       owner    = bob
       currency = "USD"

compiler/damlc/tests/daml-test-files/List.daml

@@ -16,7 +16,7 @@ import DA.Assert
 import DA.Optional
 
 data Foo = Foo with x : Int; y : Text
-  deriving Eq
+  deriving (Eq, Show)
 
 testSort6 = scenario do
   let l = [ Foo 42 "a"
@@ -24,14 +24,14 @@ testSort6 = scenario do
           , Foo 15 "c"
           , Foo 5 "b" ]
   let m = sortOn (\t -> (Down t.y, Down t.x)) l
-  assert $ head m == Foo 15 "c"
-  assert $ last m == Foo 42 "a"
+  head m === Foo 15 "c"
+  last m === Foo 42 "a"
 
 -- Utility called on by 'testSort4' and 'testSort5'
 check45 n m = do
-    assert $ n == [1, 1, 1, 2, 3]
+    n === [1, 1, 1, 2, 3]
     let o = map (\(_, f) -> f ()) m
-    assert $ o == ["A", "B", "C", "D", "E"]
+    o === ["A", "B", "C", "D", "E"]
 
 testSort5 = scenario do
     let l = [ (2, const "D"), (1, const "A"), (1, const "B"), (3, const "E"), (1, const "C") ]
@@ -48,38 +48,38 @@ testSort4 = scenario do
 testSort3 = scenario do
     let l = [ "C", "A", "E", "D", "B" ]
     let m = sort l
-    assert $ m == ["A", "B", "C", "D", "E"]
+    m === ["A", "B", "C", "D", "E"]
 
 testSort2 = scenario do
     let l = [ 4, 5, 6, 3, 9, 2, 1, 8, 7 ]
     let m = sortBy (\x y -> compare y x) l
-    assert $ m == reverse [1, 2, 3, 4, 5, 6, 7, 8, 9]
+    m === reverse [1, 2, 3, 4, 5, 6, 7, 8, 9]
 
 testSort1 = scenario do
     let l = [ 4, 5, 6, 3, 9, 2, 1, 8, 7 ]
     let m = sort l
-    assert $ m == [1, 2, 3, 4, 5, 6, 7, 8, 9]
+    m === [1, 2, 3, 4, 5, 6, 7, 8, 9]
 
 testSortEmpty = scenario do
     let l = [] : [Int]
     let m = sort l
-    assert $ m == l
+    m === l
 
 testSortIsStable = scenario do
     let l = [(1, 3), (1,2), (1,1), (1,1), (1,4)]
     let m = sortBy (compare `on` fst) l
-    assert $ m == l
+    m === l
        where on cmp f x y = cmp (f x) (f y)
 
 testGroupOn = scenario do
     let l = [(1, 3), (1,2), (1,1), (1,1), (1,4)]
     let m = groupOn ( (== 1) . snd ) l
-    assert $ m == [[(1, 3), (1,2)], [(1,1), (1,1)], [(1,4)]]
+    m === [[(1, 3), (1,2)], [(1,1), (1,1)], [(1,4)]]
 
 testDedup = scenario do
     let l = [4,7,2,1,3,5,7,2,4,2,3,4,7,2,4,2,3,4,4,5,7,7,2]
     let m = dedup l
-    assert $ m == [4,7,2,1,3,5]
+    m === [4,7,2,1,3,5]
 
 testUnique = scenario do
     unique [1, 3, 4] === True
@@ -88,7 +88,7 @@ testUnique = scenario do
     unique [1, 3, 1, 4] === False
 
 data Employee = Employee with employeeNo : Int; surname : Text; forename : Text
-    deriving (Eq)
+    deriving (Eq, Show)
 
 testUniqueOn = scenario do
     uniqueOn (.employeeNo) [ Employee 1 "Monday" "Jo", Employee 1 "Tuesday" "Bo" ] === False
@@ -96,8 +96,8 @@ testUniqueOn = scenario do
     uniqueOn (.employeeNo) ([] : [Employee]) === True
 
 testDedupOn = scenario do
-    assert $ dedupOn (.employeeNo) [ Employee 1 "Monday" "Jo", Employee 1 "Tuesday" "Bo" ] == [ Employee 1 "Monday" "Jo" ]
-    assert $ dedupOn (.employeeNo) [ Employee 1 "Monday" "Jo", Employee 2 "Monday" "Jo", Employee 3 "Tuesday" "Bo"  ] == [ Employee 1 "Monday" "Jo", Employee 2 "Monday" "Jo", Employee 3 "Tuesday" "Bo"  ]
+    dedupOn (.employeeNo) [ Employee 1 "Monday" "Jo", Employee 1 "Tuesday" "Bo" ] === [ Employee 1 "Monday" "Jo" ]
+    dedupOn (.employeeNo) [ Employee 1 "Monday" "Jo", Employee 2 "Monday" "Jo", Employee 3 "Tuesday" "Bo"  ] === [ Employee 1 "Monday" "Jo", Employee 2 "Monday" "Jo", Employee 3 "Tuesday" "Bo"  ]
     assert $ null $ dedupOn (.employeeNo) ([] : [Employee])
 
 testUniqueBy = scenario do
@@ -109,7 +109,7 @@ testUniqueBy = scenario do
 testDedupSort = scenario do
     let l = [4,7,2,1,3,5,7,2,4,2,3,4,7,2,4,2,3,4,4,5,7,7,2]
     let m = dedupSort l
-    assert $ m == [1,2,3,4,5,7]
+    m === [1,2,3,4,5,7]
 
 testDedupBy = scenario do
   [2, 1, 3] === dedupBy compare [2, 1, 3, 2, 1]
@@ -327,29 +327,29 @@ testNth = scenario do
 
 testElemIndex = scenario do
   let x = [5, 4, 6, 7, 9, 4]
-  assert $ elemIndex 7 x == Some 3
-  assert $ elemIndex 5 x == Some 0
-  assert $ elemIndex 4 x == Some 1
+  elemIndex 7 x === Some 3
+  elemIndex 5 x === Some 0
+  elemIndex 4 x === Some 1
   assert $ isNone $ elemIndex 10 x
 
 testFindIndex = scenario do
   let x = [5, 4, 6, 7, 9, 4]
-  assert $ findIndex (>6) x == Some 3
-  assert $ findIndex (>0) x == Some 0
-  assert $ findIndex (<5) x == Some 1
+  findIndex (>6) x === Some 3
+  findIndex (>0) x === Some 0
+  findIndex (<5) x === Some 1
   assert $ isNone $ findIndex (>10) x
 
 testSum = scenario do
-  assert $ sum [1, 2, 3] == 6
-  assert $ sum [] == 0
-  assert $ sum [] == (0.0 : Decimal)
-  assert $ sum [40.0, 2.0] == (42.0 : Decimal)
+  sum [1, 2, 3] === 6
+  sum [] === 0
+  sum [] === (0.0 : Decimal)
+  sum [40.0, 2.0] === (42.0 : Decimal)
 
 testProduct = scenario do
-  assert $ product [1, 2, 3] == 6
-  assert $ product [] == 1
-  assert $ product [] == (1.0 : Decimal)
-  assert $ product [21.0, 2.0] == (42.0 : Decimal)
+  product [1, 2, 3] === 6
+  product [] === 1
+  product [] === (1.0 : Decimal)
+  product [21.0, 2.0] === (42.0 : Decimal)
 
 testDelete = scenario do
   delete "a" ["b","a","n","a","n","a"] === ["b","n","a","n","a"]

compiler/damlc/tests/daml-test-files/ListComprehension.daml

@@ -4,5 +4,7 @@
 
 module ListComprehension where
 
+import DA.Assert
+
 test = scenario do
-  assert $ [n | n <- [1..10], n % 2 == 0] == [2*n | n <- [1..5]]
+  [n | n <- [1..10], n % 2 == 0] === [2*n | n <- [1..5]]

compiler/damlc/tests/daml-test-files/ListEq.daml

@@ -4,9 +4,9 @@
 
 module ListEq where
 
+import DA.Assert
+
 main = scenario do
-  alice <- getParty "alice"
-  submit alice do
-    assert $ [1] == [1]
-    assert $ [1.0] /= ([2.0] : [Decimal])
-    assert $ [""] /= []
+  [1] === [1]
+  [1.0] =/= ([2.0] : [Decimal])
+  [""] =/= []

compiler/damlc/tests/daml-test-files/MaybeCompat.daml

@@ -1,18 +1,19 @@
 -- Copyright (c) 2020, Digital Asset (Switzerland) GmbH and/or its affiliates.
 -- All rights reserved.
 
--- @WARN range=14:12-14:17; Maybe
--- @WARN range=17:12-17:17; maybe
--- @WARN range=17:29-17:36; Nothing
--- @WARN range=18:12-18:20; fromSome
--- @WARN range=18:22-18:26; Just
+-- @WARN range=15:12-15:17; Maybe
+-- @WARN range=18:3-18:8; maybe
+-- @WARN range=18:20-18:27; Nothing
+-- @WARN range=19:3-19:11; fromSome
+-- @WARN range=19:13-19:17; Just
 
 module MaybeCompat where
+import DA.Assert
 import DA.Maybe
 import DA.Maybe.Total ()  -- we want to make sure there are not warnings in this module
 
 type Foo = Maybe Int
 
 main = scenario do
-  assert $ maybe 0 identity Nothing == 0
-  assert $ fromJust (Just 1) == 1
+  maybe 0 identity Nothing === 0
+  fromJust (Just 1) === 1

compiler/damlc/tests/daml-test-files/MonoidTest.daml

@@ -4,12 +4,13 @@
 
 module MonoidTest where
 
+import DA.Assert
 import DA.Monoid
 
 testSum = scenario do
-  assert $ Sum (1 : Int) <> Sum 2 == Sum (1 + 2)
-  assert $ mempty == Sum (aunit : Int)
+  Sum (1 : Int) <> Sum 2 === Sum (1 + 2)
+  mempty === Sum (aunit : Int)
 
 testProduct = scenario do
-  assert $ Product (2 : Int) <> Product 3 == Product (2 * 3)
-  assert $ mempty == Product (munit : Int)
+  Product (2 : Int) <> Product 3 === Product (2 * 3)
+  mempty === Product (munit : Int)

compiler/damlc/tests/daml-test-files/MoreChoiceObserverDivulgence.daml

@@ -3,6 +3,8 @@
 
 module MoreChoiceObserverDivulgence where
 
+import DA.Assert
+
 -- @SINCE-LF 1.11
 
 -- This example is a small modification of `DiscloseViaChoiceObserver`, but now the divulgence is achieved using a separate `Divulger` template, with a `Divulge` choice, which does a `fetch` on the given `id`, in the view of a choice-observer.
@@ -30,7 +32,7 @@ template Divulger with
         _ <- fetch id
         pure ()
 
--- @WARN range=47:15-47:67; Use of divulged contracts is deprecated
+-- @WARN range=49:15-49:67; Use of divulged contracts is deprecated
 test : Scenario ()
 test = scenario do
     alice <- getParty "Alice"
@@ -45,5 +47,5 @@ test = scenario do
       exercise divulger Divulge with divulgee = bob; id
     -- (4) Now Bob can see the secret
     secret <- submit bob do exercise id Reveal with receiver = bob
-    assert (secret == "s3cr3t")
+    secret === "s3cr3t"
     pure ()

compiler/damlc/tests/daml-test-files/Nat.daml

@@ -3,8 +3,10 @@
 
 module Nat where
 
+import DA.Assert
+
 data Nat = Z | S Nat
-      deriving (Eq,Ord)
+      deriving (Eq,Ord,Show)
 
 
 add : Nat -> Nat -> Nat
@@ -12,5 +14,4 @@ add Z x = x
 add (S x) y = add x (S y)
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert $ add (S (S Z)) (S Z) == S (S (S Z))
+    add (S (S Z)) (S Z) === S (S (S Z))

compiler/damlc/tests/daml-test-files/Newtype.daml

@@ -4,6 +4,8 @@
 
 module Newtype where
 
+import DA.Assert
+
 newtype Nat = Nat{unNat : Int}
 
 mkNat : Int -> Nat
@@ -30,7 +32,7 @@ unNat3 : Nat -> Int
 unNat3 n = unNat n
 
 main = scenario do
-  assert $ unNat zero0 == 0
-  assert $ unNat1 one1 == 1
-  assert $ unNat2 (mkNat 2) == 2
-  assert $ unNat3 (unsafeMkNat 3) == 3
+  unNat zero0 === 0
+  unNat1 one1 === 1
+  unNat2 (mkNat 2) === 2
+  unNat3 (unsafeMkNat 3) === 3

compiler/damlc/tests/daml-test-files/NewtypeDerive.daml

@@ -4,10 +4,12 @@
 
 module NewtypeDerive where
 
+import DA.Assert
+
 newtype New a = New a deriving (Eq, Ord, Show, Functor)
 
 main = scenario do
-  assert $ New "x" == New "x"
+  New "x" === New "x"
   assert $ New 1 < New 2
-  assert $ show (New 1) == "New 1"
-  assert $ fmap (+1) (New 1) == New 2
+  show (New 1) === "New 1"
+  fmap (+1) (New 1) === New 2

compiler/damlc/tests/daml-test-files/NewtypeHigherKinded.daml

@@ -8,6 +8,8 @@
 
 module NewtypeHigherKinded where
 
+import DA.Assert
+
 newtype App f a = App (f a)
 
 newtype Wrap a = Wrap a
@@ -19,4 +21,4 @@ unwrap : Functor f => App f (Wrap a) -> f a
 unwrap (App xs) = fmap (\(Wrap x) -> x) xs
 
 main = scenario do
-  assert (unwrap (wrap [1]) == [1])
+  unwrap (wrap [1]) === [1]

compiler/damlc/tests/daml-test-files/NewtypeNested.daml

@@ -4,6 +4,7 @@
 
 module NewtypeNested where
 
+import DA.Assert
 import Newtype
 
 newtype Nat' = Nat' Nat
@@ -15,4 +16,4 @@ unNat' : Nat' -> Nat
 unNat' (Nat' n) = n
 
 main = scenario do
-  assert $ unNat (unNat' (mkNat' (mkNat 1))) == 1
+  unNat (unNat' (mkNat' (mkNat 1))) === 1

compiler/damlc/tests/daml-test-files/NewtypePolymorphic.daml

@@ -4,6 +4,8 @@
 
 module NewtypePolymorphic where
 
+import DA.Assert
+
 newtype T a = T a
 
 mkT : a -> T a
@@ -13,4 +15,4 @@ unT : T a -> a
 unT (T x) = x
 
 main = scenario do
-  assert (unT (mkT 1) == 1)
+  unT (mkT 1) === 1

compiler/damlc/tests/daml-test-files/NumericLit.daml

@@ -9,6 +9,7 @@
 
 module NumericLit where
 
+import DA.Assert
 import DA.Numeric (pi)
 
 pi0 : Numeric 0
@@ -27,8 +28,8 @@ pi37 : Numeric 37
 pi37 = 3.14159_26535_89793_23846_26433_83279_50288_41
 
 piTest = scenario $ do
-    assert $ pi == pi0
-    assert $ pi == pi5
-    assert $ pi == pi10
-    assert $ pi == pi15
-    assert $ pi == pi37
+    pi === pi0
+    pi === pi5
+    pi === pi10
+    pi === pi15
+    pi === pi37

compiler/damlc/tests/daml-test-files/PatternSynonyms.daml

@@ -6,6 +6,8 @@
 
 module PatternSynonyms where
 
+import DA.Assert
+
 type Box = Optional
 
 pattern Empty : Box a
@@ -23,5 +25,5 @@ mapOptional f = \case
 
 main = scenario do
   let f : Int -> Text = show
-  assert $ mapOptional f Empty == Empty
-  assert $ mapOptional f (Filled 1) == Filled "1"
+  mapOptional f Empty === Empty
+  mapOptional f (Filled 1) === Filled "1"

compiler/damlc/tests/daml-test-files/Phantom.daml

@@ -3,8 +3,10 @@
 
 module Phantom where
 
+import DA.Assert
+
 data Phantom a = Phantom {}
-    deriving Eq
+    deriving (Eq, Show)
 phantom : Phantom (Party -> Party)
 phantom = Phantom {}
 
@@ -12,7 +14,5 @@ showOptional : (a -> Text) -> Optional a -> Text
 showOptional f x = optional "None" f x
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice do
-        assert $ phantom == Phantom {}
-        assert $ showOptional show (None : Optional Int) == "None"
+  phantom === Phantom {}
+  showOptional show (None : Optional Int) === "None"

compiler/damlc/tests/daml-test-files/PreludeTest.daml

@@ -1,7 +1,7 @@
 -- Copyright (c) 2020, Digital Asset (Switzerland) GmbH and/or its affiliates.
 -- All rights reserved.
 
--- @INFO range=54:27-54:43; Use uncurry
+-- @INFO range=54:19-54:35; Use uncurry
 -- @INFO range=68:9-68:19; Redundant identity
 -- @INFO range=69:13-69:27; Redundant identity
 -- @INFO range=70:23-70:61; Redundant identity
@@ -17,8 +17,8 @@
 -- @INFO range=120:13-120:38; Use &&
 -- @INFO range=122:13-122:37; Use &&
 -- @INFO range=123:12-123:28; Use &&
--- @INFO range=159:12-159:36; Use isNone
--- @INFO range=159:21-159:35; Use $>
+
+-- @INFO range=159:13-159:27; Use $>
 -- @INFO range=165:10-165:56; Evaluate
 -- @INFO range=166:10-166:59; Evaluate
 -- @INFO range=179:17-179:36; Use ++
@@ -48,17 +48,17 @@ import DA.Date
 
 testDollar = scenario do
     let x1 = (+) 3 $ (*) 2 10
-    assert $ 23 == 23
+    23 === 23
 
 testCurry = scenario do
-    assert $ 23 == curry (\(x, y) -> x + y) 20 3
+    23 === curry (\(x, y) -> x + y) 20 3
 
 testUncurry = scenario do
-    assert $ 23 == uncurry (+) (20, 3)
+    23 === uncurry (+) (20, 3)
 
 testPow = scenario do
-    assert $ 256 == 2^8
-    assert $ 2^2^2^2 == 65536
+    256 === 2^8
+    2^2^2^2 === 65536
 
 testRemainder = scenario do
   1 === 6 % 5
@@ -156,7 +156,7 @@ testOptional = scenario do
 
   None === fmap (+1) (fail "")
   None === do None; pure 1
-  assert $ None == (None *> pure 1)
+  None === (None *> pure 1)
 
   5 === optional 5 T.length None
   5 === optional 5 T.length (Some "12345")
@@ -326,27 +326,27 @@ testFixedpoint = scenario do
   89 === fixedpoint (\f x -> if x < 2 then 1 else f (x-1) + f (x-2)) 10
 
 testIntToDecimal = scenario do
-    assert $ intToDecimal 1 == 1.0
-    assert $ intToDecimal (-7) == (-7.0)
-    assert $ intToDecimal 0 == 0.0
+    intToDecimal 1 === 1.0
+    intToDecimal (-7) === (-7.0)
+    intToDecimal 0 === 0.0
 
 testTruncate = scenario do
-    assert $ truncate (14.9 : Decimal) == 14
-    assert $ truncate (15.0 : Decimal) == 15
-    assert $ truncate ((-9.3) : Decimal) == (-9)
-    assert $ truncate (0.0 : Decimal) == 0
+    truncate (14.9 : Decimal) === 14
+    truncate (15.0 : Decimal) === 15
+    truncate ((-9.3) : Decimal) === (-9)
+    truncate (0.0 : Decimal) === 0
 
 testCeiling = scenario do
-    assert $ ceiling (14.9 : Decimal) == 15
-    assert $ ceiling (15.0 : Decimal) == 15
-    assert $ ceiling ((-9.3) : Decimal) == (-9)
-    assert $ ceiling (0.0 : Decimal) == 0
+    ceiling (14.9 : Decimal) === 15
+    ceiling (15.0 : Decimal) === 15
+    ceiling ((-9.3) : Decimal) === (-9)
+    ceiling (0.0 : Decimal) === 0
 
 testFloor = scenario do
-    assert $ floor (14.9 : Decimal) == 14
-    assert $ floor (15.0 : Decimal) == 15
-    assert $ floor ((-9.3) : Decimal) == (-10)
-    assert $ floor (0.0 : Decimal) == 0
+    floor (14.9 : Decimal) === 14
+    floor (15.0 : Decimal) === 15
+    floor ((-9.3) : Decimal) === (-10)
+    floor (0.0 : Decimal) === 0
 
 testRound = scenario do
     roundCommercial 0 10.5 === (11.0 : Decimal)
@@ -361,13 +361,13 @@ testRound = scenario do
 testNth = scenario do
     let l = [1, 5, 10]
     let v = l !! 1
-    assert $ v == 5
+    v === 5
 
 testDiv = scenario do
-    assert $ 10.0 / 2.0 == (5.0 : Decimal)
-    assert $ 13.2 / 5.0 == (2.64 : Decimal)
+    10.0 / 2.0 === (5.0 : Decimal)
+    13.2 / 5.0 === (2.64 : Decimal)
 
-    assert $ 0.5 == recip (2.0 : Decimal)
+    0.5 === recip (2.0 : Decimal)
     1.0 / 3.0 === (0.3333333333 : Decimal)
     1.0 / 3.0 * 3.0 === (0.9999999999 : Decimal)
 
@@ -379,9 +379,9 @@ testDiv = scenario do
     5 / (-3) === -1
 
 testDayOfWeek = scenario do
-    assert $ dayOfWeek (date 1900 Jan 01) == Monday
-    assert $ dayOfWeek (date 2018 Jan 17) == Wednesday
-    assert $ dayOfWeek (date 2020 Feb 29) == Saturday
+    dayOfWeek (date 1900 Jan 01) === Monday
+    dayOfWeek (date 2018 Jan 17) === Wednesday
+    dayOfWeek (date 2020 Feb 29) === Saturday
 
 testDateOverflow = scenario do
     pure $ date 2100 Feb 29

compiler/damlc/tests/daml-test-files/Rank2.daml

@@ -7,9 +7,10 @@
 
 module Rank2 where
 
+import DA.Assert
+
 applyBoth : (forall c . [c] -> [c]) -> ([a], [b]) -> ([a], [b])
 applyBoth f (a,b) = (f a, f b)
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert $ applyBoth reverse ([1,2,3],["a","b"]) == ([3,2,1],["b","a"])
+  applyBoth reverse ([1,2,3],["a","b"]) === ([3,2,1],["b","a"])

compiler/damlc/tests/daml-test-files/RecordsMore.daml

@@ -4,32 +4,34 @@
 
 module RecordsMore where
 
+import DA.Assert
+
 -- Tests for 'HasField' record preprocessor rewrites.
 
-data A = A with x: Int deriving Eq
-data B = B with y: A; z: A deriving Eq
-data C = C {a : Int, b : Int} deriving Eq
+data A = A with x: Int deriving (Eq, Show)
+data B = B with y: A; z: A deriving (Eq, Show)
+data C = C {a : Int, b : Int} deriving (Eq, Show)
 
 main = scenario do
 
   f <- return $ \ x y z -> x {a = y, b = z}
-  assert $ f C{a = 1, b = 2} 3 4 == C{a = 3, b = 4}
+  f C{a = 1, b = 2} 3 4 === C{a = 3, b = 4}
   f <- return $ \ x y z -> x {a = y + z}
-  assert $ f C{a = 1, b = 2} 1 2 == C{a = 3, b = 2}
+  f C{a = 1, b = 2} 1 2 === C{a = 3, b = 2}
   f <- return $ \ x a -> B a with x a with x
-  assert $ f 1 A{x = 12} == B (A 1) (A 1)
+  f 1 A{x = 12} === B (A 1) (A 1)
   f <- return $ \ a -> a {x = a.x + 1}
-  assert $ (f A{x = 1}).x == 2
+  (f A{x = 1}).x === 2
   f <- return $ \b -> b {y = b.y, z = b.z{x = 4}}
-  assert $ (f B{y = A{x = 1}, z = A{x = 2}}).z.x == 4
-  assert $ let res = f B{y = A{x = 1}, z = A{x = 2}} in res.z.x == 4
+  (f B{y = A{x = 1}, z = A{x = 2}}).z.x === 4
+  let res = f B{y = A{x = 1}, z = A{x = 2}} in res.z.x === 4
   f <- return $ \b -> b {y = b.y, z = b.z{x = (\ x -> x * x) b.z.x}}
-  assert $ (f B{y = A{x = 1}, z = A{x = 2}}).z.x == 4
+  (f B{y = A{x = 1}, z = A{x = 2}}).z.x === 4
   f <- return $ \b -> b {y = b.y{x = b.y.x + 1}, z = b.z{x = (\ x -> x * x) b.z{x = b.z.x}.x}}
-  assert $ (f B{y = A{x = 1}, z = A{x = 2}}).y.x == 2
-  assert $ (f B{y = A{x = 1}, z = A{x = 2}}).z.x == 4
+  (f B{y = A{x = 1}, z = A{x = 2}}).y.x === 2
+  (f B{y = A{x = 1}, z = A{x = 2}}).z.x === 4
 
   f <- return $ \ l -> map (.x) l
-  assert $ f [A 1, A 2, A 3] == [1, 2, 3]
+  f [A 1, A 2, A 3] === [1, 2, 3]
   f <- return $ \ l -> map (.y.x) l
-  assert $ f [B (A 1) (A 2), B (A 2) (A 3), B (A 3) (A 4)] == [1, 2, 3]
+  f [B (A 1) (A 2), B (A 2) (A 3), B (A 3) (A 4)] === [1, 2, 3]

compiler/damlc/tests/daml-test-files/Self.daml

@@ -4,6 +4,8 @@
 
 module Self where
 
+import DA.Assert
+
 template Self with
     p: Party
   where
@@ -12,7 +14,7 @@ template Self with
   controller p can
     Same : ()
       with other: ContractId Self
-      do assert (self == other)
+      do self === other
 
 main = scenario do
   alice <- getParty "Alice"

compiler/damlc/tests/daml-test-files/Self2.daml

@@ -4,6 +4,8 @@
 
 module Self2 where
 
+import DA.Assert
+
 template Self2
   with
     p : Party
@@ -33,5 +35,4 @@ main = scenario do
   r <- submit alice do
     cid <- create $ Self2 alice
     exercise cid Foo
-  assert $ r == "ok"
-
+  r === "ok"

compiler/damlc/tests/daml-test-files/SemigroupTest.daml

@@ -4,8 +4,9 @@
 
 module SemigroupTest where
 
+import DA.Assert
 import DA.Semigroup
 
 test = scenario do
-  assert $ Min (23 : Int) <> Min 42 == Min 23
-  assert $ Max (23 : Int) <> Max 42 == Max 42
+  Min (23 : Int) <> Min 42 === Min 23
+  Max (23 : Int) <> Max 42 === Max 42

compiler/damlc/tests/daml-test-files/Sha256.daml

@@ -1,8 +1,7 @@
--- @SINCE-LF 1.2
-
 module Sha256 where
 
+import DA.Assert
 import DA.Text as T
 
 test = scenario do
-  assert (T.sha256 "foo" == "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae")
+  T.sha256 "foo" === "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"

compiler/damlc/tests/daml-test-files/SugarUnit.daml

@@ -9,8 +9,10 @@
 
 module SugarUnit where
 
+import DA.Assert
+
 data Foo a = Foo a
-    deriving (Eq)
+    deriving (Eq, Show)
 
 joinFoo ffx =
     -- The desugaring of this nested pattern produces a `GHC.Tuple.Unit`.
@@ -18,4 +20,4 @@ joinFoo ffx =
     in Foo x
 
 test = scenario do
-    assert $ joinFoo (Foo (Foo 1)) == Foo 1
+    joinFoo (Foo (Foo 1)) === Foo 1

compiler/damlc/tests/daml-test-files/SumProducts.daml

@@ -4,19 +4,21 @@
 
 module SumProducts where
 
+import DA.Assert
+
 data SumOfProducts
     = Sum1 {field1 : Int, field2 : Text}
     | Sum2
     | Sum3 {field1 : Int, field3 : Optional Text, field4 : Bool}
     | Sum4 Int
-      deriving (Eq,Ord)
+      deriving (Eq,Ord, Show)
 
 main = scenario do
     let sum1 = Sum1 3 "test"
     let sum3 = Sum3 3 None True
     let sum4 = Sum4 5
     let sum4s = map Sum4 [1, 2]
-    assert $ sum1 /= Sum2
+    sum1 =/= Sum2
     assert $ sum1 < Sum2
     assert $ sum3 < sum4
-    assert $ sum1.field1 == sum3.field1
+    sum1.field1 === sum3.field1

compiler/damlc/tests/daml-test-files/Text.daml

@@ -26,11 +26,11 @@ testLength = scenario do
   3 === T.length "abc"
 
 testTrim = scenario do
-    assert $  trim "  digital asset  " == "digital asset"
+     trim "  digital asset  " === "digital asset"
 
 testReplace = scenario do
-    assert $ replace "el" "_" "Hello Bella" == "H_lo B_la"
-    assert $ replace "el" "e" "Hello"       == "Helo"
+    replace "el" "_" "Hello Bella" === "H_lo B_la"
+    replace "el" "e" "Hello"       === "Helo"
 
 testLines = scenario do
   [] === lines ""
@@ -51,20 +51,20 @@ testUnwords = scenario do
   unwords ["one", "two"] === "one two"
 
 testLinesBy = scenario do
-    assert $ linesBy (== "a") "aabbaca"  == ["","","bb","c"]
-    assert $ linesBy (== "a") "aabbacaa" == ["","","bb","c",""]
+    linesBy (== "a") "aabbaca"  === ["","","bb","c"]
+    linesBy (== "a") "aabbacaa" === ["","","bb","c",""]
     assert $ null $ linesBy (== "a") ""
-    assert $ linesBy (== "a") "a"        == [""]
-    assert $ linesBy (== ":") "::xyz:abc::123::" == ["","","xyz","abc","","123",""]
-    assert $ linesBy (== ",") "my,list,here" == ["my","list","here"]
+    linesBy (== "a") "a"        === [""]
+    linesBy (== ":") "::xyz:abc::123::" === ["","","xyz","abc","","123",""]
+    linesBy (== ",") "my,list,here" === ["my","list","here"]
 
 testWordsBy = scenario do
-    assert $ wordsBy (== "a") "aabbaca"  == ["bb","c"]
-    assert $ wordsBy (== "a") "aabbacaa" == ["bb","c"]
+    wordsBy (== "a") "aabbaca"  === ["bb","c"]
+    wordsBy (== "a") "aabbacaa" === ["bb","c"]
     assert $ null $ wordsBy (== "a") ""
     assert $ null $ wordsBy (== "a") "a"
-    assert $ wordsBy (== ":") "::xyz:abc::123::" == ["xyz","abc","123"]
-    assert $ wordsBy (== ",") "my,list,here" == ["my","list","here"]
+    wordsBy (== ":") "::xyz:abc::123::" === ["xyz","abc","123"]
+    wordsBy (== ",") "my,list,here" === ["my","list","here"]
 
 testIntercalate = scenario do
   "1, 2, 3" === intercalate ", " ["1", "2", "3"]
@@ -73,22 +73,22 @@ testIntercalate = scenario do
   "" === intercalate ", " []
 
 testDropPrefix = scenario do
-    assert $ dropPrefix "Mr. " "Mr. Men" == "Men"
-    assert $ dropPrefix "Mr. " "Dr. Men" == "Dr. Men"
+    dropPrefix "Mr. " "Mr. Men" === "Men"
+    dropPrefix "Mr. " "Dr. Men" === "Dr. Men"
 
 testDropSuffix = scenario do
-    assert $ dropSuffix "!" "Hello World!"  == "Hello World"
-    assert $ dropSuffix "!" "Hello World!!" == "Hello World!"
-    assert $ dropSuffix "!" "Hello World."  == "Hello World."
+    dropSuffix "!" "Hello World!"  === "Hello World"
+    dropSuffix "!" "Hello World!!" === "Hello World!"
+    dropSuffix "!" "Hello World."  === "Hello World."
 
 testStripSuffix = scenario do
-    assert $ stripSuffix "bar" "foobar" == Some "foo"
-    assert $ stripSuffix ""    "baz"    == Some "baz"
+    stripSuffix "bar" "foobar" === Some "foo"
+    stripSuffix ""    "baz"    === Some "baz"
     assert $ isNone $ stripSuffix "foo" "quux"
 
 testStripPrefix = scenario do
-    assert $ stripPrefix "foo" "foobar" == Some "bar"
-    assert $ stripPrefix ""    "baz"    == Some "baz"
+    stripPrefix "foo" "foobar" === Some "bar"
+    stripPrefix ""    "baz"    === Some "baz"
     assert $ isNone $ stripPrefix "foo" "quux"
 
 testIsPrefixOf = scenario do

compiler/damlc/tests/daml-test-files/TextEq.daml

@@ -3,6 +3,7 @@
 
 
 module TextEq where -- test of DEL-3881
+import DA.Assert
 
 stringEdit x = case x of
   "USD" -> "JPY"
@@ -10,7 +11,6 @@ stringEdit x = case x of
   x -> x
 
 main = scenario do
-    alice <- getParty "alice"
-    submit alice $ assert $ stringEdit "USD" == "JPY"
-    submit alice $ assert $ stringEdit "JPY" == "USD"
-    submit alice $ assert $ stringEdit "DAML" == "DAML"
+    stringEdit "USD" === "JPY"
+    stringEdit "JPY" === "USD"
+    stringEdit "DAML" === "DAML"

compiler/damlc/tests/daml-test-files/TextMap.daml

@@ -45,11 +45,11 @@ testNull = scenario do
 
 testEq = scenario do
   (TM.empty : TextMap Int) === (TM.empty : TextMap Int)
-  assert (TM.empty /= TM.fromList [("1", 1)])
+  TM.empty =/= TM.fromList [("1", 1)]
   TM.fromList [("1", 1), ("2", 2), ("3", 3)] === TM.fromList [("1", 1), ("2", 2), ("3", 3)]
-  assert (TM.fromList [("1", 1), ("2", 2), ("3", 3)] /= TM.fromList [("1", 2), ("2", 2)])
-  assert (TM.fromList [("1", 1), ("2", 2), ("3", 3)] /= TM.fromList [("1", 2), ("2", 2), ("3", 4)])
-  assert (TM.fromList [("1", 1), ("2", 2), ("3", 3)] /= TM.fromList [("1", 2), ("2", 2), ("4", 3)])
+  TM.fromList [("1", 1), ("2", 2), ("3", 3)] =/= TM.fromList [("1", 2), ("2", 2)]
+  TM.fromList [("1", 1), ("2", 2), ("3", 3)] =/= TM.fromList [("1", 2), ("2", 2), ("3", 4)]
+  TM.fromList [("1", 1), ("2", 2), ("3", 3)] =/= TM.fromList [("1", 2), ("2", 2), ("4", 3)]
 
 testInsert = scenario do
   [("1", True), ("2", False), ("3", True), ("4", False), ("5", False)]

compiler/damlc/tests/daml-test-files/Trace.daml

@@ -2,8 +2,9 @@
 -- All rights reserved.
 
 module Trace where
+import DA.Assert
 
 main = scenario do
   debug "using traceA in a scenario"
   alice <- traceId <$> getParty "Alice"
-  submit alice $ assert $ traceId 1 == trace "custom trace message" 1
+  traceId 1 === trace "custom trace message" 1

compiler/damlc/tests/daml-test-files/Tuple.daml

@@ -43,7 +43,7 @@ testThd3 = scenario do
   True === thd3 (1, "A", True)
 
 testCurry3 = scenario do
-    assert $ 123 == curry3 (\(x, y, z) -> x + y + z) 20 3 100
+    123 === curry3 (\(x, y, z) -> x + y + z) 20 3 100
 
 testUncurry3 = scenario do
-    assert $ 123 == uncurry3 (\x y z -> x + y + z) (20, 3, 100)
+    123 === uncurry3 (\x y z -> x + y + z) (20, 3, 100)

compiler/damlc/tests/daml-test-files/UseInteger.daml

@@ -1,7 +1,5 @@
 -- Copyright (c) 2020, Digital Asset (Switzerland) GmbH and/or its affiliates.
 -- All rights reserved.
-
--- @INFO Use negate
 -- @INFO Use negate
 
 -- Test that foo does not overflow
@@ -12,11 +10,11 @@
 
 module UseInteger where
 
+import DA.Assert
+
 foo = 1
 bar = 9223372036854775807 -- maxBound :: Int64 (*)
 
 main = scenario do
-  alice <- getParty "alice"
-  submit alice do
-      assertMsg "Was not one" (foo == 1)
-      assert $ 0 - foo - bar == 0 - 2^62 - 2^62 -- minBound :: Int64
+  foo === 1
+  0 - foo - bar === 0 - 2^62 - 2^62 -- minBound :: Int64