Fix buffering mistake in handling of compiler directives

src/lsp/cobol_preproc/preproc_engine.ml

@@ -188,7 +188,7 @@ let rec next_chunk ({ srclex; buff; _ } as lp) =
       | Error `NotCDir ->
           preprocess_line { lp with srclex; buff = [] } (buff @ text)
       | Ok ([], lexdir_text) ->
-          next_chunk @@ on_lexing_directive lp lexdir_text
+          next_chunk @@ on_lexing_directive { lp with srclex } lexdir_text
       | Ok (text, lexdir_text) ->
           let lp = { lp with srclex; buff = [] } in
           preprocess_line (on_lexing_directive lp lexdir_text) (buff @ text)
@@ -228,7 +228,7 @@ and preprocess_line lp srctext =
                                         be a compiler directive. *)
       preprocess_line lp srctext
   | Ok (`ReplaceDone (lp, text, srctext)) ->
-      text, with_buff lp srctext
+      text, with_buff lp @@ Text.strip_eof srctext
   | Error (`MissingPeriod | `MissingText) ->
       next_chunk (with_buff lp srctext)
 

src/lsp/cobol_preproc/src_lexing.ml

@@ -90,11 +90,12 @@ let flushed = function
 (** Flush buffered lexing productions, possibly holding onto one that may be
     subject to continuation on the following line.
 
-    Always flushes completely whenever a compiler-directive word has been seen.
+    Always flushes completely whenever a compiler-directive word has been seen,
+    or upon end-of-input/file.
 *)
 let flush ({ lex_prods; _ } as state) : _ state * text =
   match lex_prods with
-  | h :: prods when not state.cdir_seen ->
+  | h :: prods when not state.cdir_seen && ~&h <> Eof ->
       { state with lex_prods = [h]                   }, List.rev prods
   | prods ->
       { state with lex_prods = []; cdir_seen = false }, List.rev prods

src/lsp/cobol_preproc/text.ml

@@ -132,3 +132,8 @@ let pseudotext_of_string = pseudotext_ pseudo_string
 let pseudotext_of_alphanum = pseudotext_ pseudo_alphanum
 let pseudotext_of_integer = pseudotext_ pseudo_integer
 let alphanum_as_pseudotext a = pseudotext_ alphanum_as_pseudo a
+
+(** Strips any end-of-input/file item from the beginning of the given text. *)
+let rec strip_eof = function
+  | { payload = Eof; _ } :: text -> strip_eof text
+  | text -> text

src/lsp/cobol_preproc/text.mli

@@ -61,3 +61,4 @@ val pp_alphanum: alphanum Pretty.printer
 
 val prefix_of_literal_kind: literal_kind -> string
 val char_of_quotation: quotation -> char
+val strip_eof: text -> text