Parser: recover on unfinished namespaces and top level modules

Author: auduchinok

src/Compiler/pars.fsy

@@ -527,13 +527,22 @@ moduleIntro:
         let mModule = rhs parseState 1
         mModule, $4, [], $3, $2 }
 
+  | moduleKeyword opt_attributes opt_access opt_rec recover
+      { if not (isNil $2) then
+            parseState.LexBuffer.CheckLanguageFeatureAndRecover LanguageFeature.AttributesToRightOfModuleKeyword (rhs parseState 4)
+        let mModule = rhs parseState 1
+        mModule, $4, [], $3, $2 }
 
 /* The start of a namespace declaration */
 namespaceIntro:
   | NAMESPACE opt_rec path
       { let mNamespace = rhs parseState 1
         mNamespace, $2, $3.LongIdent, grabXmlDoc(parseState, [], 1) }
 
+  | NAMESPACE opt_rec recover
+      { let mNamespace = rhs parseState 1
+        mNamespace, $2, [], grabXmlDoc(parseState, [], 1) }
+
 
 /* The contents of a signature file */
 fileNamespaceSpecs:
@@ -1138,8 +1147,8 @@ fileModuleImpl:
   | moduleDefnsOrExprPossiblyEmptyOrBlock
     { let m = (rhs parseState 1)
       (fun (mNamespaceOpt, isRec, path, xml) ->
-        match path with
-        | [] -> ParsedImplFileFragment.AnonModule($1, m)
+        match path, mNamespaceOpt with
+        | [], None -> ParsedImplFileFragment.AnonModule($1, m)
         | _ ->
             let lastDeclRange = List.tryLast $1 |> Option.map (fun decl -> decl.Range) |> Option.defaultValue (rhs parseState 1)
             let m = mkRange lastDeclRange.FileName (lhs parseState).Start lastDeclRange.End

tests/service/data/SyntaxTree/ModuleOrNamespace/Anon module 01.fs

@@ -0,0 +1 @@
+()

tests/service/data/SyntaxTree/ModuleOrNamespace/Anon module 01.fs.bsl

@@ -0,0 +1,12 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleOrNamespace/Anon module 01.fs", false,
+      QualifiedNameOfFile Anon module 01, [], [],
+      [SynModuleOrNamespace
+         ([Anon module 01], false, AnonModule,
+          [Expr (Const (Unit, (1,0--1,2)), (1,0--1,2))], PreXmlDocEmpty, [],
+          None, (1,0--1,2), { LeadingKeyword = None })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(1,0)-(1,2) parse warning The declarations in this file will be placed in an implicit module 'Anon module 01' based on the file name 'Anon module 01.fs'. However this is not a valid F# identifier, so the contents will not be accessible from other files. Consider renaming the file or adding a 'module' or 'namespace' declaration at the top of the file.

tests/service/data/SyntaxTree/ModuleOrNamespace/Anon module 02.fsx

@@ -0,0 +1 @@
+()

tests/service/data/SyntaxTree/ModuleOrNamespace/Anon module 02.fsx.bsl

@@ -0,0 +1,10 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleOrNamespace/Anon module 02.fsx", true,
+      QualifiedNameOfFile Anon module 02$fsx, [], [],
+      [SynModuleOrNamespace
+         ([Anon module 02], false, AnonModule,
+          [Expr (Const (Unit, (1,0--1,2)), (1,0--1,2))], PreXmlDocEmpty, [],
+          None, (1,0--1,2), { LeadingKeyword = None })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))

tests/service/data/SyntaxTree/ModuleOrNamespace/Module 05.fs

@@ -0,0 +1,3 @@
+module A.
+
+()

tests/service/data/SyntaxTree/ModuleOrNamespace/Module 05.fs.bsl

@@ -0,0 +1,12 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleOrNamespace/Module 05.fs", false, QualifiedNameOfFile A, [],
+      [],
+      [SynModuleOrNamespace
+         ([A], false, NamedModule, [Expr (Const (Unit, (3,0--3,2)), (3,0--3,2))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--3,2), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,0)-(3,1) parse error Unexpected start of structured construct in definition

tests/service/data/SyntaxTree/ModuleOrNamespace/Module 06.fs

@@ -0,0 +1,3 @@
+module
+
+()

tests/service/data/SyntaxTree/ModuleOrNamespace/Module 06.fs.bsl

@@ -0,0 +1,12 @@
+ImplFile
+  (ParsedImplFileInput
+     ("/root/ModuleOrNamespace/Module 06.fs", false, QualifiedNameOfFile , [],
+      [],
+      [SynModuleOrNamespace
+         ([], false, NamedModule, [Expr (Const (Unit, (3,0--3,2)), (3,0--3,2))],
+          PreXmlDoc ((1,0), FSharp.Compiler.Xml.XmlDocCollector), [], None,
+          (1,0--3,2), { LeadingKeyword = Module (1,0--1,6) })], (true, true),
+      { ConditionalDirectives = []
+        CodeComments = [] }, set []))
+
+(3,0)-(3,1) parse error Unexpected start of structured construct in definition. Expected identifier, 'global' or other token.

tests/service/data/SyntaxTree/ModuleOrNamespace/Module 07.fs

@@ -0,0 +1,3 @@
+module rec
+
+()