Fix vanity alignment from multiline match expression

Fixes fsharp/fslang-design#646
nblockchain · Jan 3, 2022 · dccd6da · dccd6da
1 parent 63a7eb5
commit dccd6da
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Showing 2 changed files with 54 additions and 1 deletion.
diff --git a/src/Fantomas.Tests/PatternMatchingTests.fs b/src/Fantomas.Tests/PatternMatchingTests.fs
@@ -2087,3 +2087,45 @@ match foo with
     ) -> bar ()
 | _ -> ()
 """
+
+[<Test>]
+let ``vanity alignment removed from multiline match expression`` () =
+    formatSourceString
+        false
+        """
+match directoryRouter.GetIdentity()
+      |> self.ServerDescriptors.TryFind with
+| None -> CircuitNodeDetail.FastCreate
+| Some serverDescriptor -> self.ConvertToCircuitNodeDetail serverDescriptor
+"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+match
+    directoryRouter.GetIdentity()
+    |> self.ServerDescriptors.TryFind
+    with
+| None -> CircuitNodeDetail.FastCreate
+| Some serverDescriptor -> self.ConvertToCircuitNodeDetail serverDescriptor
+"""
+
+[<Test>]
+let ``match expression covering one line`` () =
+    formatSourceString
+        false
+        """
+match directoryRouter.GetIdentity() with
+| None -> CircuitNodeDetail.FastCreate
+| Some serverDescriptor ->
+    self.ConvertToCircuitNodeDetail serverDescriptor"""
+        config
+    |> prepend newline
+    |> should
+        equal
+        """
+match directoryRouter.GetIdentity() with
+| None -> CircuitNodeDetail.FastCreate
+| Some serverDescriptor -> self.ConvertToCircuitNodeDetail serverDescriptor
+"""
diff --git a/src/Fantomas/CodePrinter.fs b/src/Fantomas/CodePrinter.fs
@@ -1614,7 +1614,10 @@ and genExpr astContext synExpr ctx =
                 +> expressionFitsOnRestOfLine
                     (genExpr astContext e
                      +> genWithAfterMatch withRange)
-                    (genExprInIfOrMatch astContext e
+                    (genExprInIfOrMatch
+                        { astContext with
+                              IsInsideMatchClausePattern = true }
+                        e
                      +> (sepNlnUnlessLastEventIsNewline
                          +> (genWithAfterMatch withRange)))
 
@@ -3320,6 +3323,14 @@ and genExprInIfOrMatch astContext (e: SynExpr) (ctx: Context) : Context =
         let fallback =
             if hasCommentBeforeExpr e then
                 genExpr astContext e |> indentNlnUnindentNln
+            elif astContext.IsInsideMatchClausePattern then
+                indent
+                +> sepNln
+                +> genExpr
+                    { astContext with
+                          IsInsideMatchClausePattern = false }
+                    e
+                +> unindent
             else
                 sepNlnWhenWriteBeforeNewlineNotEmpty sepNone
                 +> genExpr astContext e