Correct body SynExpr of parsedData of Lambda when wildcards are invol…

…ved.
dotnet · Jul 3, 2021 · 91f0148 · 91f0148
1 parent 5cfd7ff
commit 91f0148
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Showing 2 changed files with 74 additions and 2 deletions.
diff --git a/src/fsharp/SyntaxTreeOps.fs b/src/fsharp/SyntaxTreeOps.fs
@@ -195,19 +195,30 @@ let rec SimplePatsOfPat synArgNameGenerator p =
     | SynPat.Tuple (false, ps, m)
 
     | SynPat.Paren(SynPat.Tuple (false, ps, _), m) ->
+        let filteredPs =
+            List.choose
+                (fun p ->
+                    let p' = SimplePatOfPat synArgNameGenerator p
+                    match (fst p') with
+                    | SynSimplePat.Id(isCompilerGenerated = true) -> None
+                    | _ -> Some p')
+                ps
+
         let ps2, laterF =
           List.foldBack
             (fun (p', rhsf) (ps', rhsf') ->
               p':: ps',
               (composeFunOpt rhsf rhsf'))
-            (List.map (SimplePatOfPat synArgNameGenerator) ps)
+            filteredPs
             ([], None)
         SynSimplePats.SimplePats (ps2, m),
         laterF
 
     | SynPat.Paren(SynPat.Const (SynConst.Unit, m), _)
 
-    | SynPat.Const (SynConst.Unit, m) ->
+    | SynPat.Const (SynConst.Unit, m)
+
+    | SynPat.Wild m ->
         SynSimplePats.SimplePats ([], m),
         None
 

diff --git a/tests/service/Symbols.fs b/tests/service/Symbols.fs
@@ -1225,4 +1225,65 @@ module ParsedHashDirective =
         ]) ])) ->
             Assert.AreEqual("40", v)
             assertRange (1, 8) (1, 16) m
+        | _ -> Assert.Fail "Could not get valid AST"
+
+module Lambdas =
+    [<Test>]
+    let ``Lambda with two parameters gives correct body`` () =
+        let parseResults = 
+            getParseResults
+                "fun a b -> x"
+
+        match parseResults with
+        | ParsedInput.ImplFile (ParsedImplFileInput (modules = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.DoExpr(
+                expr = SynExpr.Lambda(parsedData = Some(_, SynExpr.Ident(ident)))
+            )
+        ]) ])) ->
+            Assert.AreEqual("x", ident.idText)
+        | _ -> Assert.Fail "Could not get valid AST"
+
+    [<Test>]
+    let ``Lambda with wild card parameter gives correct body`` () =
+        let parseResults = 
+            getParseResults
+                "fun a _ b -> x"
+
+        match parseResults with
+        | ParsedInput.ImplFile (ParsedImplFileInput (modules = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.DoExpr(
+                expr = SynExpr.Lambda(parsedData = Some(_, SynExpr.Ident(ident)))
+            )
+        ]) ])) ->
+            Assert.AreEqual("x", ident.idText)
+        | _ -> Assert.Fail "Could not get valid AST"
+
+    [<Test>]
+    let ``Lambda with tuple parameter with wild card gives correct body`` () =
+        let parseResults = 
+            getParseResults
+                "fun a (b, _) c -> x"
+
+        match parseResults with
+        | ParsedInput.ImplFile (ParsedImplFileInput (modules = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.DoExpr(
+                expr = SynExpr.Lambda(parsedData = Some(_, SynExpr.Ident(ident)))
+            )
+        ]) ])) ->
+            Assert.AreEqual("x", ident.idText)
+        | _ -> Assert.Fail "Could not get valid AST"
+
+    [<Test>]
+    let ``Lambda with wild card that returns a lambda gives correct body`` () =
+        let parseResults = 
+            getParseResults
+                "fun _ -> fun _ -> x"
+
+        match parseResults with
+        | ParsedInput.ImplFile (ParsedImplFileInput (modules = [ SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.DoExpr(
+                expr = SynExpr.Lambda(parsedData = Some(_, SynExpr.Lambda(parsedData = Some(_, SynExpr.Ident(ident)))))
+            )
+        ]) ])) ->
+            Assert.AreEqual("x", ident.idText)
         | _ -> Assert.Fail "Could not get valid AST"