Proposal to split parameters of function application over multiple li…

…nes.
nojaf · Jun 26, 2020 · 6a28f6f · 6a28f6f
1 parent b4444b8
commit 6a28f6f
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Showing 3 changed files with 27 additions and 50 deletions.
diff --git a/src/Fantomas.Tests/AppTests.fs b/src/Fantomas.Tests/AppTests.fs
@@ -68,19 +68,15 @@ let a s =
     |> should equal @"
 let a s =
     if s <> """" then
-        printfn
-            """"""fooo
+        printfn """"""fooo
 %s
 %s
 %s
-%s""""""
-            (llloooooooooooooooooooooooooo s)
-            s
+%s""""""    (llloooooooooooooooooooooooooo s) s
             (llloooooooooooooooooooooooooo s)
             (llloooooooooooooooooooooooooo s)
 "
 
-
 [<Test>]
 let ``should split parameters over multiple lines when they exceed page width``() =
     formatSourceString false """module Caching =

diff --git a/src/Fantomas.Tests/ElmishTests.fs b/src/Fantomas.Tests/ElmishTests.fs
@@ -433,9 +433,11 @@ table [ ClassName "table table-striped table-hover mb-0" ] [
         tokenDetailRow "ColorClass" (str colorClass)
         tokenDetailRow "CharClass" (str charClass)
         tokenDetailRow "Tag" (ofInt tag)
-        tokenDetailRow "FullMatchedLength" (span [ ClassName "has-text-weight-semibold" ] [
-                                                ofInt fullMatchedLength
-                                            ])
+        tokenDetailRow
+            "FullMatchedLength"
+            (span [ ClassName "has-text-weight-semibold" ] [
+                ofInt fullMatchedLength
+             ])
     ]
 ]
 """

diff --git a/src/Fantomas/CodePrinter.fs b/src/Fantomas/CodePrinter.fs
@@ -1322,48 +1322,17 @@ and genExpr astContext synExpr =
             else
                 sepSpace ctx
 
-        // This checks if there is an application with multiple parameters which would fit in one line
-        // but at least one of the parameters which is not the last parameter has a line comment 
-        // In that case we have to split the arguments over multiple lines to preserve the line comments
-        // Example:
-        //
-        //     someFunc a b c // comment
-        //
-        // This can stay as is because the last argument has the line comment
-        // However:
-        //
-        //     someFunc
-        //         a 
-        //         b // comment
-        //         c
-        //
-        // This has to be split over multiple lines to preserve the line comment
-        let parametersMustBeNewlinedBecauseOfTriviaContent es ctx =
-            es
-            |> List.map (fun (e:SynExpr) -> TriviaHelpers.findByRange ctx.Trivia e.Range)
-            |> List.mapi (fun i node -> if node.IsSome && not (i = List.length es - 1) then TriviaHelpers.``has line comment after`` node.Value else false)
-            |> List.contains true
-
-        fun ctx ->
-            let shortExpression = 
-                (atCurrentColumn
-                    (genExpr astContext e
-                    +> colPre sepSpace sepSpace es (fun e ->
-                    ifElse (isCompExpr e)
-                        (sepSpace
-                        +> sepOpenSFixed
-                        +> sepSpace
+        let shortExpression =
+            atCurrentColumn
+                (genExpr astContext e
+                 +> colPre sepSpace sepSpace es (fun e ->
+                        onlyIf (isCompExpr e) (sepSpace +> sepOpenSFixed +> sepSpace)
                         +> indent
                         +> appNlnFun e (indentIfNeeded +> genExpr astContext e)
-                        +> unindent)
-                        (indent
-                        +> indentIfNeeded
-                        +> sepNln
-                        +> genExpr astContext e
-                        +> unindent))))
+                        +> unindent))
 
-            let longExpression =
-                (atCurrentColumn
+        let longExpression =
+            (atCurrentColumn
                 (genExpr astContext e
                 +> colPre sepSpace sepSpace es (fun e ->
                 ifElse (isCompExpr e)
@@ -1375,11 +1344,21 @@ and genExpr astContext synExpr =
                     +> unindent)
                     (indent
                     +> indentIfNeeded
+                    +> sepNln
                     +> genExpr astContext e
                     +> unindent))))
 
-            //ifElseCtx (fun ctx -> exceedsWidth ctx.Config.PageWidth longExpression ctx || parametersMustBeNewlinedBecauseOfTriviaContent es ctx) shortExpression longExpression ctx
-            ifElseCtx (fun ctx -> parametersMustBeNewlinedBecauseOfTriviaContent es ctx) shortExpression (expressionFitsOnRestOfLine longExpression shortExpression) ctx
+        if List.exists (function
+            | Lambda _
+            | MatchLambda _
+            | Paren (Lambda (_))
+            | Paren (MatchLambda (_))
+            | MultilineString _
+            | CompExpr _ -> true
+            | _ -> false) es then
+            shortExpression
+        else
+            expressionFitsOnRestOfLine shortExpression longExpression
 
     | TypeApp(e, ts) -> genExpr astContext e -- "<" +> col sepComma ts (genType astContext false) -- ">"
     | LetOrUses(bs, e) ->