Recover from incomplete module declaration

src/Compiler/FSComp.txt

@@ -1677,3 +1677,4 @@ featureEscapeBracesInFormattableString,"Escapes curly braces before calling Form
 3558,chkExplicitFieldsDeclarationsOnStaticClasses,"If a type uses both [<Sealed>] and [<AbstractClass>] attributes, it means it is static. Explicit field declarations are not allowed."
 3559,typrelNeverRefinedAwayFromTop,"A type has been implicitly inferred as 'obj', which may be unintended. Consider adding explicit type annotations. You can disable this warning by using '#nowarn \"3559\"' or '--nowarn:3559'."
 3560,tcCopyAndUpdateRecordChangesAllFields,"This copy-and-update record expression changes all fields of record type '%s'. Consider using the record construction syntax instead."
+3562,parsIncompleteNestedModule,"Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file."

src/Compiler/SyntaxTree/LexFilter.fs

@@ -1562,7 +1562,7 @@ type LexFilterImpl (
         //  Otherwise it's a 'head' module declaration, so ignore it
 
         //  Here prevToken is either 'module', 'rec', 'global' (invalid), '.', or ident, because we skip attribute tokens and access modifier tokens
-        | _, CtxtModuleHead (moduleTokenPos, prevToken, lexingModuleAttributes) :: _ ->
+        | _, CtxtModuleHead (moduleTokenPos, prevToken, lexingModuleAttributes) :: rest ->
             match prevToken, token with
             | _, GREATER_RBRACK when lexingModuleAttributes = LexingModuleAttributes
                                      && moduleTokenPos.Column < tokenStartPos.Column ->
@@ -1587,19 +1587,28 @@ type LexFilterImpl (
                 pushCtxt tokenTup (CtxtModuleBody (moduleTokenPos, false))
                 pushCtxtSeqBlock(true, AddBlockEnd)
                 returnToken tokenLexbufState token
-            | _ -> 
-                if debug then dprintf "CtxtModuleHead: start of file, CtxtSeqBlock\n"
-                popCtxt()
-                // Don't push a new context if next token is EOF, since that raises an offside warning
-                match tokenTup.Token with 
-                | EOF _ -> 
-                    returnToken tokenLexbufState token
+            | _ ->
+                match rest with
+                | [ CtxtSeqBlock _ ] ->
+                    if debug then dprintf "CtxtModuleHead: start of file, CtxtSeqBlock\n"
+                    popCtxt()
+                    // Don't push a new context if next token is EOF, since that raises an offside warning
+                    match tokenTup.Token with 
+                    | EOF _ -> 
+                        returnToken tokenLexbufState token
+                    | _ ->
+                        // We have reached other tokens without encountering '=' or ':', so this is a module declaration spanning the whole file
+                        delayToken tokenTup 
+                        pushCtxt tokenTup (CtxtModuleBody (moduleTokenPos, true))
+                        pushCtxtSeqBlockAt (tokenTup, true, AddBlockEnd) 
+                        hwTokenFetch false
                 | _ ->
-                    // We have reached other tokens without encountering '=' or ':', so this is a module declaration spanning the whole file
-                    delayToken tokenTup 
-                    pushCtxt tokenTup (CtxtModuleBody (moduleTokenPos, true))
-                    pushCtxtSeqBlockAt (tokenTup, true, AddBlockEnd) 
-                    hwTokenFetch false
+                    // Adding a new nested module, EQUALS hasn't been typed yet
+                    // and we've encountered declarations below
+                    if debug then dprintf "CtxtModuleHead: MODULE/LET, popping CtxtModuleHead\n"
+                    popCtxt()
+                    reprocessWithoutBlockRule()
+
         //  Offside rule for SeqBlock.  
         //      f x
         //      g x

src/Compiler/pars.fsy

@@ -1280,6 +1280,16 @@ moduleDefn:
             let trivia: SynModuleDeclNestedModuleTrivia = { ModuleKeyword = Some mModule; EqualsRange = Some mEquals }
             [ SynModuleDecl.NestedModule(info, isRec, def, false, ((rhs2 parseState 1 4, def) ||> unionRangeWithListBy (fun d -> d.Range) |> unionRangeWithXmlDoc xmlDoc), trivia)] }
 
+  /* incomplete 'module' definitions */
+  | opt_attributes opt_access moduleIntro
+      { let xmlDoc = grabXmlDoc(parseState, $1, 1)
+        let mWhole = rhs2 parseState 1 3 |> unionRangeWithXmlDoc xmlDoc
+        errorR(Error(FSComp.SR.parsIncompleteNestedModule(), mWhole))
+        let attribs, (mModule, isRec, path, vis, attribs2) = $1, $3
+        let info = SynComponentInfo(attribs @ attribs2, None, [], path, xmlDoc, false, vis, rhs parseState 3)
+        let trivia: SynModuleDeclNestedModuleTrivia = { ModuleKeyword = Some mModule; EqualsRange = None }
+        [ SynModuleDecl.NestedModule(info, isRec, [], false, mWhole, trivia)] }
+
   /* unattached custom attributes */
   | attributes recover
       { errorR(Error(FSComp.SR.parsAttributeOnIncompleteCode(), rhs parseState 1))

src/Compiler/xlf/FSComp.txt.cs.xlf

@@ -382,19 +382,16 @@
         <target state="translated">reprezentace struktury aktivních vzorů</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">Vyvolá upozornění, když se použije „let inline ... =“ společně s atributem [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;]. Funkce není vkládána.</target>
@@ -735,6 +732,11 @@
         <target state="translated">Očekává se vzorek.</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="translated">Neúplný znakový literál (příklad: Q) nebo volání kvalifikovaného typu (příklad: T.Name)</target>

src/Compiler/xlf/FSComp.txt.de.xlf

@@ -382,19 +382,16 @@
         <target state="translated">Strukturdarstellung für aktive Muster</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">Löst Warnungen aus, wenn „let inline ... =“ zusammen mit dem Attribut [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] verwendet wird. Die Funktion wird nicht inline gesetzt.</target>
@@ -735,6 +732,11 @@
         <target state="translated">Muster wird erwartet</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="translated">Unvollständiges Zeichenliteral (Beispiel: „Q“) oder qualifizierter Typaufruf (Beispiel: „T.Name“)</target>

src/Compiler/xlf/FSComp.txt.es.xlf

@@ -382,19 +382,16 @@
         <target state="translated">representación de struct para modelos activos</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">Genera advertencias cuando se usa "let inline ... =" junto con el atributo [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;]. La función no se está insertando.</target>
@@ -735,6 +732,11 @@
         <target state="translated">Se espera un patrón</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="translated">Literal de carácter incompleto (ejemplo: 'Q') o invocación de tipo completo (ejemplo: 'T.Name)</target>

src/Compiler/xlf/FSComp.txt.fr.xlf

@@ -382,19 +382,16 @@
         <target state="translated">représentation de structure pour les modèles actifs</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">Génère des avertissements lorsque « let inline ... = » est utilisé avec l’attribut [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;]. La fonction n’est pas inlined.</target>
@@ -735,6 +732,11 @@
         <target state="translated">Modèle attendu</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="translated">Littéral de caractère incomplet (exemple : 'Q') ou appel de type qualifié (exemple : 'T.Name)</target>

src/Compiler/xlf/FSComp.txt.it.xlf

@@ -382,19 +382,16 @@
         <target state="translated">rappresentazione struct per criteri attivi</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">Genera avvisi quando 'let inline ... =' viene usato insieme all'attributo [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;]. La funzione non viene resa inline.</target>
@@ -735,6 +732,11 @@
         <target state="translated">Criterio previsto</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="translated">Valore letterale carattere incompleto (ad esempio: 'Q') o chiamata di tipo qualificato (ad esempio: 'T.Name)</target>

src/Compiler/xlf/FSComp.txt.ja.xlf

@@ -382,19 +382,16 @@
         <target state="translated">アクティブなパターンの構造体表現</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureTryWithInSeqExpressions">
         <source>Support for try-with in sequence expressions</source>
         <target state="new">Support for try-with in sequence expressions</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenCopyAndUpdateRecordChangesAllFields">
         <source>Raises warnings when an copy-and-update record expression changes all fields of a record.</source>
         <target state="new">Raises warnings when an copy-and-update record expression changes all fields of a record.</target>
         <note />
       </trans-unit>
-
       <trans-unit id="featureWarningWhenInliningMethodImplNoInlineMarkedFunction">
         <source>Raises warnings when 'let inline ... =' is used together with [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] attribute. Function is not getting inlined.</source>
         <target state="translated">'let inline ... =' が [&lt;MethodImpl(MethodImplOptions.NoInlining)&gt;] 属性と一緒に使用されるときに警告を生成します。関数はインライン化されていません。</target>
@@ -735,6 +732,11 @@
         <target state="translated">必要なパターン</target>
         <note />
       </trans-unit>
+      <trans-unit id="parsIncompleteNestedModule">
+        <source>Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</source>
+        <target state="new">Local module declarations must include the '=' sign, and their contents are indented. If this is supposed to be a top-level module instead, it must appear as the first declaration in a file.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="parsIncompleteTyparExpr1">
         <source>Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</source>
         <target state="new">Incomplete character literal (example: 'Q') or qualified type invocation (example: 'T.Name)</target>