Fix regressions (#1264)

* Fixed regression with named or patterns in match clauses.

* Fix multiline if branch expression.

* Bump to 4.3.0-alpha-007

RELEASE_NOTES.md

@@ -1,3 +1,7 @@
+### 4.3.0-alpha-007 - 11/2020
+
+* Fix regressions. [#1264](https://github.com/fsprojects/fantomas/pull/1264)
+
 ### 4.3.0-alpha-006 - 11/2020
 
 * Feature Clarify constructors. [#1217](https://github.com/fsprojects/fantomas/issues/1217)

src/Fantomas.CoreGlobalTool.Tests/Fantomas.CoreGlobalTool.Tests.fsproj

@@ -4,7 +4,7 @@
     <TargetFramework>net5.0</TargetFramework>
     <IsPackable>false</IsPackable>
     <GenerateProgramFile>false</GenerateProgramFile>
-    <Version>4.3.0-alpha-006</Version>
+    <Version>4.3.0-alpha-007</Version>
     <NoWarn>FS0988</NoWarn>
     <WarningsAsErrors>FS0025</WarningsAsErrors>
   </PropertyGroup>

src/Fantomas.CoreGlobalTool/Fantomas.CoreGlobalTool.fsproj

@@ -4,7 +4,7 @@
     <TargetFramework>net5.0</TargetFramework>
     <ToolCommandName>fantomas</ToolCommandName>
     <PackAsTool>True</PackAsTool>
-    <Version>4.3.0-alpha-006</Version>
+    <Version>4.3.0-alpha-007</Version>
     <AssemblyName>fantomas-tool</AssemblyName>
     <WarningsAsErrors>FS0025</WarningsAsErrors>
   </PropertyGroup>

src/Fantomas.Extras/Fantomas.Extras.fsproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <Version>4.3.0-alpha-006</Version>
+    <Version>4.3.0-alpha-007</Version>
     <Description>Utility package for Fantomas</Description>
     <WarningsAsErrors>FS0025</WarningsAsErrors>
   </PropertyGroup>

src/Fantomas.Tests/Fantomas.Tests.fsproj

@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <Version>4.3.0-alpha-006</Version>
+    <Version>4.3.0-alpha-007</Version>
     <NoWarn>FS0988</NoWarn>
     <TargetFramework>net5.0</TargetFramework>
     <WarningsAsErrors>FS0025</WarningsAsErrors>

src/Fantomas.Tests/IfThenElseTests.fs

@@ -1107,3 +1107,43 @@ let funcs =
             let n2Score = modifierScore n2
             if n1Score = n2Score then n1.DisplayName.CompareTo n2.DisplayName else n1Score.CompareTo n2Score)
 """
+
+[<Test>]
+let ``multiline then clause`` () =
+    formatSourceString false """
+[<EntryPoint>]
+let main argv =
+    let fileToFile (inFile: string) (outFile: string) =
+        try
+            use buffer =
+                if hasByteOrderMark
+                then new StreamWriter(new FileStream(outFile, FileMode.OpenOrCreate, FileAccess.ReadWrite),
+                                      Encoding.UTF8)
+                else new StreamWriter(outFile)
+
+            buffer.Flush()
+        with exn ->
+            eprintfn "The following exception occurred while formatting %s: %O" inFile exn
+
+    0
+"""  config
+    |> prepend newline
+    |> should equal """
+[<EntryPoint>]
+let main argv =
+    let fileToFile (inFile: string) (outFile: string) =
+        try
+            use buffer =
+                if hasByteOrderMark then
+                    new StreamWriter(
+                        new FileStream(outFile, FileMode.OpenOrCreate, FileAccess.ReadWrite),
+                        Encoding.UTF8
+                    )
+                else
+                    new StreamWriter(outFile)
+
+            buffer.Flush()
+        with exn -> eprintfn "The following exception occurred while formatting %s: %O" inFile exn
+
+    0
+"""

src/Fantomas.Tests/PatternMatchingTests.fs

@@ -821,3 +821,59 @@ let draftToken =
 
         DraftToken.Create kind token
 """
+
+[<Test>]
+let ``named pat or in clauses`` () =
+    formatSourceString false """
+let (|MFMember|MFStaticMember|MFConstructor|MFOverride|) (mf: MemberFlags) =
+    match mf.MemberKind with
+    | MemberKind.ClassConstructor
+    | MemberKind.Constructor -> MFConstructor()
+    | MemberKind.Member
+    | MemberKind.PropertyGet
+    | MemberKind.PropertySet
+    | MemberKind.PropertyGetSet as mk ->
+        if mf.IsInstance && mf.IsOverrideOrExplicitImpl
+        then MFOverride mk
+        elif mf.IsInstance
+        then MFMember mk
+        else MFStaticMember mk
+"""  config
+    |> prepend newline
+    |> should equal """
+let (|MFMember|MFStaticMember|MFConstructor|MFOverride|) (mf: MemberFlags) =
+    match mf.MemberKind with
+    | MemberKind.ClassConstructor
+    | MemberKind.Constructor -> MFConstructor()
+    | MemberKind.Member
+    | MemberKind.PropertyGet
+    | MemberKind.PropertySet
+    | MemberKind.PropertyGetSet as mk ->
+        if mf.IsInstance && mf.IsOverrideOrExplicitImpl
+        then MFOverride mk
+        elif mf.IsInstance
+        then MFMember mk
+        else MFStaticMember mk
+"""
+
+[<Test>]
+let ``named pat or in function syntax`` () =
+    formatSourceString false """
+let rec (|DoExprAttributesL|_|) =
+    function
+    | DoExpr _
+    | Attributes _ as x :: DoExprAttributesL (xs, ys) -> Some(x :: xs, ys)
+    | DoExpr _
+    | Attributes _ as x :: ys -> Some([ x ], ys)
+    | _ -> None
+"""  config
+    |> prepend newline
+    |> should equal """
+let rec (|DoExprAttributesL|_|) =
+    function
+    | DoExpr _
+    | Attributes _ as x :: DoExprAttributesL (xs, ys) -> Some(x :: xs, ys)
+    | DoExpr _
+    | Attributes _ as x :: ys -> Some([ x ], ys)
+    | _ -> None
+"""

src/Fantomas/CodePrinter.fs

@@ -38,7 +38,9 @@ type ASTContext =
       /// This is required to correctly detect the setting SpaceBeforeMember
       IsMemberDefinition: bool
       /// Check whether the context is inside a SynExpr.DotIndexedGet
-      IsInsideDotIndexed: bool }
+      IsInsideDotIndexed: bool
+      /// Inside a SynPat of MatchClause
+      IsInsideMatchClausePattern: bool }
     static member Default =
         { TopLevelModuleName = ""
           IsFirstChild = false
@@ -50,7 +52,8 @@ type ASTContext =
           IsFirstTypeParam = false
           IsInsideDotGet = false
           IsMemberDefinition = false
-          IsInsideDotIndexed = false }
+          IsInsideDotIndexed = false
+          IsInsideMatchClausePattern = false }
 
 let rec addSpaceBeforeParensInFunCall functionOrMethod arg (ctx: Context) =
     match functionOrMethod, arg with
@@ -2226,7 +2229,7 @@ and genExpr astContext synExpr ctx =
                     || futureNlnCheck (!- "if " +> genExpr astContext e1) ctx
 
                 let isIfBranchMultiline =
-                    futureNlnCheck (genExpr astContext e2) ctx
+                    futureNlnCheck (!- "then " +> genExpr astContext e2) ctx
 
                 let isElseBranchMultiline =
                     match enOpt with
@@ -4090,27 +4093,18 @@ and genClause astContext hasBar (Clause (p, e, eo)) =
     let arrowRange =
         mkRange "arrowRange" p.Range.End e.Range.Start
 
-    let pat ctx =
-        match p with
-        | PatOrs (ph :: _ as allPats) when (List.length allPats > 1) ->
-            allPats
-            |> List.pairwise
-            |> List.fold (fun acc (prev, current) ->
-                let barRange =
-                    mkRange "bar range" prev.Range.End current.Range.Start
-
-                (sepNln
-                 +> enterNodeTokenByName barRange BAR
-                 +> sepBar
-                 +> genPat astContext current) acc) (genPat astContext ph ctx)
-        | _ -> genPat astContext p ctx
-
     let body =
         optPre (!- " when ") sepNone eo (genExpr astContext)
         +> sepArrow
         +> leaveNodeTokenByName arrowRange RARROW
         +> clauseBody e
 
+    let astCtx =
+        { astContext with
+              IsInsideMatchClausePattern = true }
+
+    let pat = genPat astCtx p
+
     genTriviaBeforeClausePipe p.Range
     +> ifElse hasBar (sepBar +> atCurrentColumnWithPrepend pat body) (pat +> body)
 
@@ -4335,7 +4329,10 @@ and genComplexPats astContext node =
 
 and genPatRecordFieldName astContext (PatRecordFieldName (s1, s2, p)) =
     ifElse (s1 = "") (!-(sprintf "%s = " s2)) (!-(sprintf "%s.%s = " s1 s2))
-    +> genPat astContext p
+    +> genPat
+        { astContext with
+              IsInsideMatchClausePattern = false }
+           p // see issue 1252.
 
 and genPatWithIdent astContext (ido, p) =
     opt (sepEq +> sepSpace) ido (!-)
@@ -4352,7 +4349,7 @@ and genPat astContext pat =
             mkRange "bar range" p1.Range.End p2.Range.Start
 
         genPat astContext p1
-        +> sepSpace
+        +> ifElse astContext.IsInsideMatchClausePattern sepNln sepSpace
         +> enterNodeTokenByName barRange BAR
         -- "| "
         +> genPat astContext p2

src/Fantomas/Fantomas.fsproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <Version>4.3.0-alpha-006</Version>
+    <Version>4.3.0-alpha-007</Version>
     <Description>Source code formatter for F#</Description>
     <WarningsAsErrors>FS0025</WarningsAsErrors>
   </PropertyGroup>

src/Fantomas/SourceParser.fs

@@ -1101,13 +1101,6 @@ let (|PatOr|_|) =
     | SynPat.Or (p1, p2, _) -> Some(p1, p2)
     | _ -> None
 
-let rec (|PatOrs|_|) =
-    function
-    | PatOr (PatOrs pats, p) -> Some(pats @ [ p ])
-    | PatOr (p, PatOrs pats) -> Some(p :: pats)
-    | PatOr (p1, p2) -> Some [ p1; p2 ]
-    | _ -> None
-
 let (|PatAnds|_|) =
     function
     | SynPat.Ands (ps, _) -> Some ps
@@ -1148,7 +1141,6 @@ let (|PatTyped|_|) =
     | SynPat.Typed (p, t, _) -> Some(p, t)
     | _ -> None
 
-// of hier
 let (|PatNamed|_|) =
     function
     | SynPat.Named (p, IdentOrKeyword (OpNameFullInPattern (s, _)), _, ao, _) -> Some(ao, p, s)