Anchor equals sign in data/type declarations (#75)

Author: natefaubion

src/Tidy.purs

@@ -382,7 +382,7 @@ formatDecl conf = case _ of
       declareHanging
         (formatDataHead conf head)
         space
-        (formatToken conf equals)
+        (anchor (formatToken conf equals))
         (formatHangingDataCtor conf ctors.head)
     else
       formatDataHead conf head `flexSpaceBreak` indent do
@@ -400,14 +400,14 @@ formatDecl conf = case _ of
     declareHanging
       (formatDataHead conf head)
       space
-      (formatToken conf equals)
+      (anchor (formatToken conf equals))
       (formatHangingType conf ty)
 
   DeclNewtype head equals name ty ->
     declareHanging
       (formatDataHead conf head)
       space
-      (formatToken conf equals)
+      (anchor (formatToken conf equals))
       (formatHangingDataCtor conf (DataCtor { name, fields: [ ty ] }))
 
   DeclRole kw1 kw2 name rls ->

test/snapshots/DataDeclarations.output

@@ -0,0 +1,102 @@
+module DataDeclarations where
+
+data Test a = A | B | C | D | E | F | G | H | I | J | K | L
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+newtype Test a = Test a
+
+newtype Test a = Test a
+
+newtype Test a =
+  Test a
+
+newtype Test a =
+  Test a
+
+type Test a = a
+
+type Test a = a
+
+type Test a =
+  a
+
+type Test a =
+  a
+
+-- @format --width=40
+module DataDeclarations where
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+  | F
+  | G
+  | H
+  | I
+  | J
+  | K
+  | L
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+data Test a
+  = A
+  | B
+  | C
+  | D
+  | E
+
+newtype Test a = Test a
+
+newtype Test a = Test a
+
+newtype Test a =
+  Test a
+
+newtype Test a =
+  Test a
+
+type Test a = a
+
+type Test a = a
+
+type Test a =
+  a
+
+type Test a =
+  a

test/snapshots/DataDeclarations.purs

@@ -0,0 +1,39 @@
+-- @format --width=40
+module DataDeclarations where
+
+data Test a = A | B | C | D | E | F | G | H | I | J | K | L
+
+data Test a
+  = A | B | C | D | E
+
+data Test a
+  = A | B
+  | C | D | E
+
+data Test a =
+  A | B
+  | C | D | E
+
+newtype Test a = Test a
+
+newtype Test a
+  = Test a
+
+newtype Test a =
+  Test a
+
+newtype Test a
+  =
+  Test a
+
+type Test a = a
+
+type Test a
+  = a
+
+type Test a =
+  a
+
+type Test a
+  =
+  a