Parser: recover on unfinished open (#15377)

Author: auduchinok

src/Compiler/pars.fsy

@@ -706,7 +706,7 @@ moduleSpfn:
         SynModuleSigDecl.Exception(synExnDefn, mWhole) }
 
   | openDecl
-      { SynModuleSigDecl.Open($1, (rhs parseState 1)) }
+      { SynModuleSigDecl.Open $1 }
 
 valSpfn:
   | opt_attributes opt_access VAL opt_attributes opt_inline opt_mutable opt_access nameop opt_explicitValTyparDecls COLON topTypeWithTypeConstraints optLiteralValueSpfn
@@ -1320,15 +1320,26 @@ moduleDefn:
 
   /* 'open' declarations */
   | openDecl
-      { [ SynModuleDecl.Open($1, (rhs parseState 1)) ] }
+      { [ SynModuleDecl.Open $1 ] }
 
 openDecl:
-  /* 'open' declarations */
   | OPEN path
-      { SynOpenDeclTarget.ModuleOrNamespace($2, (rhs parseState 2)) }
+      { let mOpen = rhs parseState 1
+        let mPath = $2.Range
+        SynOpenDeclTarget.ModuleOrNamespace($2, mPath), unionRanges mOpen mPath }
+
+  | OPEN recover
+      { let mOpen = rhs parseState 1
+        SynOpenDeclTarget.ModuleOrNamespace(SynLongIdent([], [], []), mOpen.EndRange), mOpen }
 
   | OPEN typeKeyword appType
-      { SynOpenDeclTarget.Type($3, (rhs parseState 3)) }
+      { let mOpen = rhs parseState 1
+        let mPath = $3.Range
+        SynOpenDeclTarget.Type($3, mPath), unionRanges mOpen mPath }
+
+  | OPEN typeKeyword recover
+      { let m = rhs2 parseState 1 2
+        SynOpenDeclTarget.ModuleOrNamespace(SynLongIdent([], [], []), m.EndRange), m }
 
 /* The right-hand-side of a module abbreviation definition */
 /* This occurs on the right of a module abbreviation (#light encloses the r.h.s. with OBLOCKBEGIN/OBLOCKEND) */

tests/service/data/SyntaxTree/ModuleMember/Open 01.fs

@@ -0,0 +1,4 @@
+module Module
+
+open
+open Ns1

tests/service/data/SyntaxTree/ModuleMember/Open 01.fs.bsl

@@ -0,0 +1,17 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleMember/Open 01.fs", false, QualifiedNameOfFile Module, [], [],
+      [SynModuleOrNamespace
+         ([Module], false, NamedModule,
+          [Open
+             (ModuleOrNamespace (SynLongIdent ([], [], []), (3,4--3,4)),
+              (3,0--3,4));
+           Open
+             (ModuleOrNamespace (SynLongIdent ([Ns1], [], [None]), (4,5--4,8)),
+              (4,0--4,8))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--4,8), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,5)-(4,0) parse error Incomplete structured construct at or before this point in open declaration. Expected identifier, 'global', 'type' or other token.

tests/service/data/SyntaxTree/ModuleMember/Open 02.fs

@@ -0,0 +1,4 @@
+module Module
+
+open type
+open Ns1

tests/service/data/SyntaxTree/ModuleMember/Open 02.fs.bsl

@@ -0,0 +1,17 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleMember/Open 02.fs", false, QualifiedNameOfFile Module, [], [],
+      [SynModuleOrNamespace
+         ([Module], false, NamedModule,
+          [Open
+             (ModuleOrNamespace (SynLongIdent ([], [], []), (3,9--3,9)),
+              (3,0--3,9));
+           Open
+             (ModuleOrNamespace (SynLongIdent ([Ns1], [], [None]), (4,5--4,8)),
+              (4,0--4,8))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--4,8), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,10)-(4,0) parse error Incomplete structured construct at or before this point in open declaration

tests/service/data/SyntaxTree/ModuleMember/Open 03.fs

@@ -0,0 +1,5 @@
+module Module
+
+open type
+
+()

tests/service/data/SyntaxTree/ModuleMember/Open 03.fs.bsl

@@ -0,0 +1,14 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleMember/Open 03.fs", false, QualifiedNameOfFile Module, [], [],
+      [SynModuleOrNamespace
+         ([Module], false, NamedModule,
+          [Open
+             (ModuleOrNamespace (SynLongIdent ([], [], []), (3,9--3,9)),
+              (3,0--3,9)); Expr (Const (Unit, (5,0--5,2)), (5,0--5,2))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--5,2), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,10)-(5,0) parse error Incomplete structured construct at or before this point in open declaration

tests/service/data/SyntaxTree/ModuleMember/Open 04.fs

@@ -0,0 +1,5 @@
+module Module
+
+open type
+
+ignore

tests/service/data/SyntaxTree/ModuleMember/Open 04.fs.bsl

@@ -0,0 +1,14 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleMember/Open 04.fs", false, QualifiedNameOfFile Module, [], [],
+      [SynModuleOrNamespace
+         ([Module], false, NamedModule,
+          [Open
+             (ModuleOrNamespace (SynLongIdent ([], [], []), (3,9--3,9)),
+              (3,0--3,9)); Expr (Ident ignore, (5,0--5,6))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--5,6), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,10)-(5,0) parse error Incomplete structured construct at or before this point in open declaration

tests/service/data/SyntaxTree/ModuleMember/Open 05.fs

@@ -0,0 +1,5 @@
+module Module
+
+open
+
+type T = int